Book of Extended Abstracts

The access to extended abstracts is obtained by clicking on abstract title



Date: Sunday, 14/Aug/2016

8:00am - 8:00pm

Registration
Session Chair: Ariadne Flora Neves de Andrade

Exhibition Hall

9:00am - 10:30am

SuA - W1: Frontiers in TERS
Session Chair: Alexandre Rocha Paschoal

Consultant: Debdulal Roy, National Physical Laboratory, UK
Organized by the Brazilian Network for Research and Instrumentation in Optical NanoSpectroscopy

Ruby Room

10:45am - 12:15pm

SuA - W2: Coherent 3D imaging

Consultant: Carlos Lenz Cesar
Organized by National Institute of Photonics Applied to Cell Biology - INFABIC

Ruby Room

1:00pm - 2:30pm

SuP - W3: Raman Spectroscopy in Art and Archaeology

Consultant: Thiago Sevilhano Puglieri
Sponsored by Renishaw

Ruby Room

2:45pm - 4:15pm

SuP - W4: Phonons and Symmetry

Consultant: Marcos A. Pimenta
Organized by National Institute of Nanocarbon Materials

Ruby Room

4:30pm - 6:00pm

SuP - W5: Modern Chemometrics
Session Chair: Alejandro Pedro Ayala

Ruby Room

6:30pm - 10:30pm

Get-Together

Exhibition Hall

Date: Monday, 15/Aug/2016

8:50am - 9:30am

Welcome Notes and Opening Ceremony

Ruby Room

9:30am - 10:30am

MoA - O - 001: Keynote Session
Session Chair: Antonio Gomes Souza Filho

Ruby Room

10:30am - 11:00am

Coffee Break

Exhibition Hall

11:00am - 12:40pm

MoA - O - 002: SERS and Applications
Session Chair: Mustafa Culha

Ruby Room

11:00am - 12:40pm

MoA - O - 003: Biomedical Applications
Session Chair: Sophie Lecomte

Esmeralda Room

11:00am - 12:40pm

MoA - O - 004: Raman Instrumentation & Industrial Applications
Session Chair: Martin Maiwald

Ametista Room

11:00am - 12:40pm

MoA - O - 005: Non-Linear and Time Resolved Spectroscopy
Session Chair: Paul Champion

Topázio Room

11:00am - 12:40pm

MoA - O - 006: Solid State
Session Chair: Carlos William Paschoal

Safira Room

12:40pm - 2:30pm

Lunch Break

 

2:30pm - 4:00pm

MoP - O - 001: SERS and Applications
Session Chair: Alexandre Brolo

Ruby Room

2:30pm - 4:00pm

MoP - O - 002: Biological Applications
Session Chair: Janina Kneipp

Esmeralda Room

2:30pm - 4:00pm

MoP - O - 003: Raman Imaging
Session Chair: Dongho Kim

Ametista Room

2:30pm - 4:00pm

MoP - O - 004: Art and Archeology
Session Chair: Thiago Sevilhano Puglieri

Topázio Room

2:30pm - 4:00pm

MoP - O - 005: Carbon Materials
Session Chair: Cristiano Fantini

Safira Room

4:00pm - 4:30pm

Coffee Break

Exhibition Hall

4:30pm - 5:00pm

MoP - O - 006: Poster Highlights
Session Chair: Paul Champion

Ruby Room

5:00pm - 8:00pm

Opening Industrial Exhibition

Exhibition Hall

5:00pm - 8:00pm

MoP-P-IA: Raman Optical Activity

Exhibition Hall

5:00pm - 8:00pm

MoP-P-IB: Biological and Biomedical Applications

Exhibition Hall

5:00pm - 8:00pm

MoP-P-IC: Materials

Exhibition Hall

Date: Tuesday, 16/Aug/2016

8:30am - 8:50am

Welcome Coffee

 

8:50am - 10:30am

TuA - O - 001: Plenary Session
Session Chair: Carlos Lenz Cesar

Ruby Room

10:30am - 11:00am

Coffee Break

Exhibition Hall

11:00am - 11:50am

TuA - O - 002: Plenary Session
Session Chair: Alejandro Pedro Ayala

Ruby Room

11:50am - 6:30pm

Excursions

 

Date: Wednesday, 17/Aug/2016

8:30am - 8:50am

Welcome Coffee

 

8:50am - 10:30am

WeA - O - 001: Plenary Session
Session Chair: Marcos A Pimenta

Ruby Room

10:30am - 11:00am

Coffee Break

Exhibition Hall

11:00am - 12:40pm

WeA - O - 002: SERS and Biological Applications
Session Chair: Lawrence Ziegler

Ruby Room

11:00am - 12:40pm

WeA - O - 003: 2D Materials
Session Chair: Ping-Heng Tan

Esmeralda Room

11:00am - 12:40pm

WeA - O - 004: Raman Instrumentation & Industrial Applications
Session Chair: S. L. Zhang

Ametista Room

11:00am - 12:40pm

WeA - O - 005: Non-Linear Raman Spectroscopy
Session Chair: Wolfgang Kiefer

Topázio Room

11:00am - 12:40pm

WeA - O - 006: TERS and Applications
Session Chair: Volker Deckert

Safira Room

12:40pm - 2:30pm

Lunch Break

 

2:30pm - 4:00pm

WeP - O - 001: SERS and Applications
Session Chair: Antonio Carlos Sant'Ana

Ruby Room

2:30pm - 4:00pm

WeP - O - 002: Biological Applications
Session Chair: Olivier Piot

Esmeralda Room

2:30pm - 4:00pm

WeP - O - 003: Carbon Materials
Session Chair: Leandro Malard

Ametista Room

2:30pm - 4:00pm

WeP - O - 004: Non-Linear and Time Resolved Spectroscopy
Session Chair: Tullio Scopigno

Topázio Room

2:30pm - 4:00pm

WeP - O - 005: Stimulated Raman and IR imaging
Session Chair: Alexandre Rocha Paschoal

Safira Room

2:30pm - 7:00pm

WeP - O - 007: 1st German-Brazilian on Photonic Health Technologies
Session Chair: Juergen Popp
Session Chair: Airton A Martin

Diagnosis, Monitoring and Therapy: New Approaches and Governance Mechanisms for Science and Technology Cooperation

 

4:00pm - 4:30pm

Coffee Break

Exhibition Hall

4:30pm - 5:00pm

WeP - O - 006: Poster Highlights
Session Chair: Lawrence Ziegler

Ruby Room

5:00pm - 7:00pm

WeP-P-IIA: SERS and Applications

Exhibition Hall

5:00pm - 7:00pm

WeP-P-IIB: Resonance Raman

Exhibition Hall

5:00pm - 7:00pm

WeP-P-IIC: Pharmaceuticals/Biomolecules

Exhibition Hall

5:00pm - 7:00pm

WeP-P-IID: Materials (nanoparticles, semiconductors)

Exhibition Hall

5:00pm - 7:00pm

WeP-P-IIE: Raman Instrumentation & Industrial Applications

Exhibition Hall

7:30pm - 11:50pm

Gala Dinner

 

Date: Thursday, 18/Aug/2016

8:30am - 8:50am

Welcome Coffee

 

8:50am - 11:10am

ThA - O - 001: Hot Topic Session - TERS
Session Chair: Ado Jorio

Ruby Room

11:10am - 11:40am

Coffee Break

Exhibition Hall

11:40am - 12:40pm

ThA - O - 002: SERS Fundamentals
Session Chair: Marek Prochazka

Ruby Room

11:40am - 12:40pm

ThA - O - 003: TERS and Applications
Session Chair: Bin Ren

Esmeralda Room

11:40am - 12:40pm

ThA - O - 004: Carbon Materials under extreme conditions
Session Chair: Paulo Tarso Cavalcante Freire

Ametista Room

12:40pm - 2:30pm

Lunch Break

 

2:30pm - 4:00pm

ThP - O - 001: Raman Metrology
Session Chair: Thiago L. Vasconcelos

Esmeralda Room

2:30pm - 4:00pm

ThP - O - 002: Forensic and Environmental Applications
Session Chair: Igor K. Lednev

Ametista Room

2:30pm - 4:00pm

ThP - O - 003: Theory
Session Chair: Pedro Venezuela

Topázio Room

4:30pm - 5:00pm

ThP - O - 004: Poster Highlights
Session Chair: Bayden Robert Wood

Ruby Room

5:00pm - 7:00pm

ThP-P-IIIA: SERS and Applications

Exhibition Hall

5:00pm - 7:00pm

ThP-P-IIIB: TERS and Applications

Exhibition Hall

5:00pm - 7:00pm

ThP-P-IIIC: RamanMetrology/Chemical Dynamics

Exhibition Hall

5:00pm - 7:00pm

ThP-P-IIID: Forensic/Geoscience/Astrobiology/Environmental Applications

Exhibition Hall

Date: Friday, 19/Aug/2016

8:30am - 8:50am

Welcome Coffee

 

8:50am - 10:30am

FrA - O - 001: Plenary Session
Session Chair: Gustavo F. S. Andrade

Ruby Room

10:30am - 11:00am

Coffee Break

Exhibition Hall

11:00am - 11:50am

FrA - O - 002: Plenary Session
Session Chair: Antonio Gomes Souza Filho

Ruby Room

11:50am - 12:40pm

Award Ceremony & Closing Remarks

Ruby Room

 

Student Workshops

9:00am - 10:30am

SuA - W1: Frontiers in TERS
Session Chair: Alexandre Rocha Paschoal

Consultant: Debdulal Roy, National Physical Laboratory, UK
Organized by the Brazilian Network for Research and Instrumentation in Optical NanoSpectroscopy

Ruby Room

10:45am - 12:15pm

SuA - W2: Coherent 3D imaging

Consultant: Carlos Lenz Cesar
Organized by National Institute of Photonics Applied to Cell Biology - INFABIC

Ruby Room

1:00pm - 2:30pm

SuP - W3: Raman Spectroscopy in Art and Archaeology

Consultant: Thiago Sevilhano Puglieri
Sponsored by Renishaw

Ruby Room

2:45pm - 4:15pm

SuP - W4: Phonons and Symmetry

Consultant: Marcos A. Pimenta
Organized by National Institute of Nanocarbon Materials

Ruby Room

4:30pm - 6:00pm

SuP - W5: Modern Chemometrics
Session Chair: Alejandro Pedro Ayala

Ruby Room

Oral Presentations

MoA - O - 001: Keynote Session

Time: Monday, 15/Aug/2016: 9:30am - 10:30am  ·  Location: Ruby Room
Session Chair: Antonio Gomes Souza Filho

History of ICORS

Wolfgang Kiefer

University of Würzburg, Germany; wolfgang.kiefer@uni-wuerzburg.de

This Opening Talk is intended to demonstrate how linear and nonlinear Raman spectroscopy has developed over half a century as reflected by the previous ICORS conferences. While in 1969 at the first ICORS meeting in Ottawa, Canada, the results of the first years of laser Raman spectroscopy were reported mainly in the physics and chemistry areas, the last ICORS in Jena (ICORS XXIV) has shown us that meanwhile this type of vibrational spectroscopy has moved into many other research fields, e.g. into life sciences. The hitherto 24 ICORSs I had been lucky to attend have brought us an enormous development in intrumentation as well as new fundamental discoveries, e.g. SERS, TERS, etc., which enhanced the sensitivity as well as the spatial resolution to many orders of magnitude which half a century ago nobody could have foreseen. While the recording of Raman spectra in the early nineteensixties with mainly He-Ne laser excitation and acceptable spectral resolution took hours of time, nowadays such spectra can be obtained in less than a second. As known, in the early laser Raman spectroscopy days the spatial resolution was limited to the size of a focused (Fourier-limited) laser beam (micrometer range), nowadays we are able to extend this range below the Abbe limit (nanometer range). With this lecture I will give a short overview over the many facettes of laser Raman spectroscopy and give some examples of important discoveries over half a century of linear and nonlinear Raman spectroscopy. The ICORS Proceedings have become an inherent part of each meeting. I will shortly inform how the publication form has meanwhile changed over the decades from the printed version to the digital one in form of CDs or USB sticks. Finally, I will report on a few outstanding social events by showing some selected short video clips and photographs which demonstrate how well-loved ICORS meetings have become meanwhile and which hopefully will motivate particularly the younger Raman spectroscopists to participate permanently in future ICORS meetings.



MoA - O - 002: SERS and Applications

Time: Monday, 15/Aug/2016: 11:00am - 12:40pm  ·  Location: Ruby Room
Session Chair: Mustafa Culha

This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Integrated Raman – FIB – SEM analysis of SERS structures

Frank J. Timmermans1, Aufried T.M. Lenferink1, Henk A.G.M. van Wolferen2, Cees Otto1

1University of Twente. Medical Cell BioPhysics, Drienerlolaan 5, 7552 NB Enschede, the Netherlands; 2University of Twente. MESA+, Drienerlolaan 5, 7552 NB Enschede, the Netherlands; f.j.timmermans@utwente.nl

An integrated correlative Raman – FIB – SEM system is applied for SERS analysis of plasmonic structures. The combination of SERS analysis, with high resolution imaging provides an accurate analysis suitable for any SERS active nanostructure. The Raman measured signal enhancement factor is compared with near field simulations based on SEM observed structure morphology. This correlative analysis enables a rigorous investigation of the SERS enhancement. It is applied for many nanoparticle clusters, with specific interest in dimer structures with varying gapsize and orientation.

Further applications are explored through FIB modification of clusters of 3-5 particles. This enables the removal of specific SERS hot spots, combined with Raman analysis before and after FIB modification reveals signal contribution from the specific hot spot.

We conclude that integrated FIB – SEM – Raman offers many possibilities for the analysis, fabrication, and modification of plasmonic structures, as demonstrated with accurate SERS enhancement analysis.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Combined AFM + Raman spectroscopy to study reaction kinetics at the nano-scale

Camiel van Hoorn1, Carlos Wessels1, Freek Ariese1, Arjan Mank2

1Faculty of Sciences and LaserLaB, Vrije Universiteit, Amsterdam, The Netherlands; 2Philips Lighting, High Tech Campus, Eindhoven, The Netherlands; c.h.van.hoorn@vu.nl

Raman spectroscopy is a valuable technique to study reaction kinetics in bulk samples. However, molecular interactions and kinetics also depend on their local environment. Therefore, it is important to get Raman spectroscopic information at the nano-scale.

In our research we use a Renishaw Raman microscope to follow the reduction of p-nitrothiophenol in a self assembles monolayer. Mappings are made to follow the reactions that take place at silver nanoparticles hotspots. We have developed data analysis methods that make it possible to study reaction kinetics at individual hotspots (50+ nm) simultaneously over a region of 100x100 micron, while information about the nanoscale structure of these catalytic sites is obtained. This way, fast screening is possible without the need for highly advanced and dedicated tools.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

A new approach to DNA and Au nanoparticles

Shirly Josefina Espinoza1,2, Philipp Bremer2, Piotr Lutoslawski1, Jakob Andreasson1, Michael Rübhausen2

1ELI Beamlines. Institute of Physics. Czech Academy of Science. Na Slovance 2. 182 21 Praha 8. Czech Republic; 2University of Hamburg. Institut für Angewandte Physik und Zentrum für Mikrostrukturforschung. CFEL. Luruper Chaussee 149. 22761 Hamburg, Germany; shirly.espinoza@eli-beams.eu

The assembly of nanoparticles aided by DNA templates is a technique that has been developed over the last years mainly due to its possible applications in plasmonics. There has been also essays using the interaction between DNA and DNA binding proteins in order to manipulate the relative position of nano- and micro-molecules inside a 3D arrange.

These studies present DNA-nanoparticles multiplexes being rearranged by DNA polymerase enzymes (Taq polymerases) with possible applications on SERS.

The initial system can be seen as a plasmon ruler formed by DNA and Au nanoparticles. Sequences of ssDNA were inserted into interparticle DNA linkage. Then, upon the addition of DNApolymerase and NTPs, the DNA polymerase walks on the ssDNA sequences and forms a dsDNA. As result of this process, the inter-particle distance increases. Raman spectra taken at different steps of the process will be presented.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Nanopillar SERS substrates for trace chemical detection: From fundamentals to sensing applications

Michael Stenbæk Schmidt

Technical University of Denmark, Denmark; mssc@nanotech.dtu.dk

We have previously presented a SERS substrate which lives up to the requirements of uniform lateral enhancement across its surface as well as being reproducible from surface to surface as well as being optically tunable and possible to be produced cost effectively on a massive scale.

We have applied this class of SERS substrates in various configurations for practical sensing applications such as point of care diagnostics (Cystic Fibrosis), environmental monitoring (Polychlorinated Biphenyls – PCB), chemical warfare agents (VX and Tabun) [3] and food safety (milk adulterants such as Melamine and antibiotic remnants). This talk will give an overview of the numerous sensing applications where we have had success measuring relevant chemical species in trace amounts as well as a look at variations of this substrate which have been optically tuned to specific sensing applications.Furthermore these substrates could enable semi-quantitative detection using SERS.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Analysis on Silver Decorated Nanostructured Metal Oxide Thin Films as Substrates for Surface Enhanced Raman Spectroscopy Application

Dhanpal Naidu Jayram1,2, G Mohan Rao1, Sonia Sathinesan2,3, Premananth karuppasamy2, Mangalaraj Devanesan2

1Plasma Processing Lab Department of Instrumentation and Applied Physics, Indian Institute of Science, Bangalore, 560012, India; 2Department of Nanoscience and Technology, Bharathiar University, Coimbatore, Tamil Nadu, 641 046, India; 3Department of Physics, Holy Cross College (Autonomous), Nagercoil, Tamil Nadu, 629004,India; dhanpal.dj@gmail.com

In recent years, Surface Enhanced Raman Spectroscopy (SERS) analysis has been developed into a noteworthy tool in various fields such as analytical chemistry, environmental monitoring, forensics and biology due to its Localized Surface Plasmon Resonance (LSPR) in nanostructured metal surfaces. Noble metal nanostructures are commonly used for SERS studies due to their strong dependence on morphology and Localized Surface Plasmon Resonance. However, metal oxides are also being preferred in view of their semiconducting properties, shape and size as well as their local dielectric environment for light scattering and coupling efficiency.The present work focuses on the fabrication of SiO2, ZnO and CuO with silver coating over their surface as active SERS substrates via physical and chemical deposition methods. The prepared nanostructures were characterized using various techniques. The obtained Ag@SiO2, Ag@ZnO, Ag@CuO, structures were subjected to (a) structure and method dependent SERS studies (b) dye dependent SERS studies and (c) Laser dependent SERS studies.


MoA - O - 003: Biomedical Applications

Time: Monday, 15/Aug/2016: 11:00am - 12:40pm  ·  Location: Esmeralda Room
Session Chair: Sophie Lecomte

This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

Real time in vivo applications of Raman spectroscopy

Airton A Martin1, Lazaro P M Neto1, Maurilio Jose das Chagas2, Luis Felipe Carvalho1, Claudio Alberto Tellez1

1Universidade do Vale do Paraíba (UniVap), Instituto de Pesquisa e Desenvolvimento (IP&D), Laboratório de Espectroscopia Vibracional Biomédica, Av. Shishima Hifumi, 2911, Urbanova, 122444-000, São José dos Campos, SP, Brazil; 2Hospital Policlin, Av. Nove de Julho, 430, Vila Ady´Anna, 12243-780, São José dos Campos, SP, Brazil; amartin@univap.br

Raman spectroscopy has been used for many applications in life science mainly due to it high sensitivity for tracing biochemical changes and the advantage of provide a non invasive and real time diagnosis. This technique has been successfully used in vitro to classify different cancer´s types with high sensitivity and specificity. More recently it has been applied in vivo to provide cancer diagnosis and information of water content, permeation and biomodulations of some specific actives on human skin. In this context the aim of this talk is to present selected application of Raman spectroscopy for cancer diagnosis and human skin analyze performed in our laboratory.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Raman Microspectroscopy for the Safety and Quality Assessment of Cardiac Tissues

Julia Marzi1, Daniel Carvajal Berrio1, Eva Brauchle1,2, Anna Biermann3, Kelvin Brockbank4, Ulrich A Stock3, Katja Schenke-Layland1,2,5

1Department of Women’s Health, Research Institute for Women's Health, Eberhard-Karls-University Tübingen, Silcherstr. 7/1, 72076 Tübingen, Germany; 2Fraunhofer Institute for Interfacial Engineering and Biotechnology (IGB), Department of Cell and Tissue Engineering, Nobelstr. 12, 70569 Stuttgart, Germany; 3University Hospital Frankfurt, Department of Thoracic-, Cardiac and Thoracic Vascular Surgery, Frankfurt, Germany; 4Tissue Testing Technologies LLC, Clemson University, Medical University of South Carolina, USA; 5Department of Medicine/ Cardiology, Cardiovascular Research Laboratories, David Geffen School of Medicine at UCLA, 675 Charles E. Young Drive South, MRL 3645, Los Angeles, CA, USA; julia.marzi@igb-extern.fraunhofer.de

For clinical application of natural and engineered tissues there is a need to improve the long-term preservation of tissues and their extracellular matrix (ECM) structures. Heart valves have three distinguishable ECM layers that are rich in collagen, elastin or proteoglycans and influence the leaflet’s biomechanical properties and functionality in vivo. Conventional cryopreservation results in intra-ECM ice formation and tissue damage, limiting the leaflet’s lifetime after transplantation. An alternative is ice-free cryopreservation (vitrification), which avoids ice formation.

Raman microspectroscopy allows for the characterization of ECM degradation. We aimed to qualitatively assess leaflet’s ECM integrity after standard and ice-free cryopreservation. Moreover, Raman microspectroscopy was applied for specific, quantitative identification of residues of potentially cytotoxic cryoprotectants.

Raman microspectroscopy and multivariate analysis enabled contact-free classification of ECM and the comparison of the differently cryopreserved cardiovascular tissues on a molecular level. Moreover, Raman microspectroscopy allowed for highly sensitive detection of penetrated cryoprotectants in the tissue.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Non-invasive Identification and Monitoring of Primary Cells and Stem Cell Differentiation

Eva Brauchle1,2, Julia Marzi2, Anne Knopf2, Hannah Bauer2, Nian Shen2, Marsha W. Rolle3, Katja Schenke-Layland1,2,4

1Department of Cell and Tissue Engineering, Fraunhofer Institute for Interfacial Engineering and Biotechnology (IGB), Nobelstrasse 12, 70569 Stuttgart,Germany; 2Department of Women’s Health, Research Institute for Women’s Health, Eberhard Karls University Tuebingen, Silcherstrasse 7/1, 72076 Tübingen, Germany; 3Department of Biomedical Engineering, Worcester Polytechnic Institute, 100 Institute Rd., Worcester, MA 01609, USA; 4Department of Medicine/Cardiology, Cardiovascular Research Laboratories, David Geffen School of Medicine at UCLA, 675 Charles E. Young Drive South, MRL 3645, Los Angeles, CA 90095, USA; eva.brauchle@igb.fraunhofer.de

Near-infrared Raman microspectroscopy offers a promising approach to identify and monitor single cells. In this study, we investigated Raman signatures from specialized primary and stem cell-derived cell phenotypes. Our results indicate that Raman spectra can help to discriminate pluripotent stem cells from their progeny and can identify subtypes of cardiomyocytes, in accordance to immunofluorescence labelling. Spectra from primary isolated cardiomyocytes and in vitro differentiated cells showed consistent Raman profiles. Primary isolated cells can change their phenotype with ongoing culture time and lose the expression of tissue-specific proteins. We could show that Raman spectral patterns are specific cell phenotypes and indicate changes of cell morphology and protein expression profiles. In conclusion, Raman microspectroscopy can be employed to monitor different stages of cell (de)differentiation and can identify cell phenotypes in a label-free manner. Due to the high molecular resolution, Raman imaging approaches could give novel insights into cell fate commitment and differentiation.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Label-Free Raman microscopy for analysis of inflammatory process and tissue repair.

Otávio Mendes Gil1, Michele Aparecida Rocha1, Vera Regina Leopoldo Constantino1, Ivan Hong Jun Koh2, Dalva Lúcia Araújo de Faria1

1University of São Paulo, Brazil; 2Federal University of São Paulo; otavio.gil@usp.br

Raman Microspectroscopy was used for temporal analysis of inflammatory response of tissue after surgical implantation of a Layered Double Hydroxide loaded with chloride ions (LDH-Cl) and Sulindac, an anti-inflammatory drug (LDH-Sul) in muscles of Wistar rats, aiming a local and modified release of the drug. Through the tissues spectral signatures it was possible to discriminate the biochemical responses through different periods and among implanted groups, identifying important components that return to tissue their physiological functionality after the tissue repair, such as the collagen fibers. The results here reported show that Raman spectroscopy stands as one of the most powerful techniques in studies of early diagnosis of inflammations and biocompatibility/biointegration of different materials.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Developing Multi-Centre Raman Imaging for Clinical Pathology

Aaran Lewis1, Martin Isabelle2, Jennifer Dorney3, Gavin Lloyd2, Riana Gaifulina1, Catherine Kendall2, Neil Shepherd2, Hugh Barr2, Katherine Lau4, Ian Bell4, Manuel Rodriguez-Justo1, Nicholas Stone3, Geraint Thomas1

1University College London, United Kingdom; 2University of Exeter, United Kingdom; 3Gloucester Hospitals NHS Foundation Trust, United Kingdom; 4Renishaw PLC, United Kingdom; aaran.lewis@ucl.ac.uk

Despite its demonstrated potential as an accurate diagnostic tool in a range of diseases, Raman spectroscopy (RS) is yet to be adopted in clinic. Our consortium is addressing key hurdles to adoption for cancer diagnosis by optimizing i) tissue sample preparation, ii) data collection, iii) pre-processing, iv) transferability and v) through building statistically sound classification models for cancers that can be incorporated into an automated classification tool. Our multiple centres have together developed a suite of sample handling protocols and an optimised spectrometer capable of being easily integrated and operated in a pathology laboratory. The project will deliver a robust, fully-integrated Raman-based diagnostic platform that will provide a tool for clinical researchers and clinicians to use to detect, classify and stage cancers, define tumour margins, and discover novel disease biomarkers.



MoA - O - 004: Raman Instrumentation & Industrial Applications

Time: Monday, 15/Aug/2016: 11:00am - 12:40pm  ·  Location: Ametista Room
Session Chair: Martin Maiwald

This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

Imaging and sensing with random Raman lasers

Vladislav V. Yakovlev

Texas A&M University, United States of America; yakovlev@tamu.edu

We demonstrate for the very first time stimulated Raman scattering in the bulk of a scattering medium. This random Raman emission shows unique properties suitable for remote sensing and speckle-free imaging.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Time-resolved Raman spectroscopy for in situ characterization of refractory materials above 2000°C

E.S FOTSO GUEUTUE, A Canizarès, N Raimboux, P MELIN, L HENNET, M AMMAR, P SIMON

CNRS, CEMHTI UPR3079, Univ. Orléans, CS 90055, F-45071 Orléans; efotsogu@cnrs-orleans.fr

Time-resolved Raman spectroscopy for in situ characterization of refractory materials above 2000°C

E.S. Fotso Gueutue, A.Canizarès, N.Raimboux,P.Melin, L Hennet, M.R.Ammar, P.Simon

CNRS, CEMHTI UPR3079, Univ. Orléans, CS 90055, F-45071 Orléans

efotsogu@cnrs-orleans.fr

Binary oxides, as Gd2O3, ZrO2, Al2O3, CeO2, Y2O3, andHfO2 have major interests in nuclear, aerospace, and refractory industries [1].These oxide materials must ensure perfect inertia and high stability in order to operate in extreme conditions such as very high temperatures, 2000°C and more. CEMHTI laboratory has developed in recent years an original time-resolved Raman spectroscopy system enabling in situ study of material properties in real time at high temperatures.


This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

The origin and suppressing of the low wavenumber stray light appeared in the grating Raman spectra

S. L. Zhang1, Yan Gong2, Wen-fan Chen1, Yan Wang2, Xiao-feng Dong1, Bo Shuang1

1Peking University, China, People's Republic of; 2School of Material Science and Engineering, Beijing Institute of Fashion Technology, China, People's Republic of; slzhang@pku.edu.cn

The Raman spectra in low wavevector region (0-150 cm-1) were excited by He-Ne laser for L-cystine, Sulfur S, Ge, SiC and GaAs. The frequency, line width and line shape can be determined clearly and are strangely equal for all of samples. Such strange feature can be only originated from the secondary maxima of Rayleigh scattering of samples. The theoretical calculation confirms the above interpretation. Besides, any Raman spectral feature doesn't appear for all samples. The results mentioned above give a solid confirmation on that the strong low wavenumber stray light in Raman spectra is originated from very strong secondary maxima spectra of Rayleigh scattering.

Recently, the measurement of low wavenumber Raman spectra becomes very important . Therefore, it is necessary to suppress the low wavenumber stray. For suppressing of Rayleigh stray spectra, some approaches with no added optical elements in spectrometer were proposed and conformed.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

New Design of Confocal Raman Microscopes and Spectrometers using Photonic Fibres

Thomas Dieing, Elena Bailo, Fernando Vargas, Olaf Hollricher

WITec GmbH, Germany; thomas.dieing@witec.de

Confocal Raman Microscopes are by now the instruments of choice for most microscopic Raman measurements. The advantages in spatial resolution in combination with highest spectral resolution allow for outstanding research in the field of Geosciences, Biology, Nano-Carbon Materials, as well as pharmaceutics, to name but a few.

One of the few limitations of systems thus far was that spatial as well as spectral resolution could often only be achieved at the cost of throughput of the system. This contribution introduces a new concept of detection using photonic fibres for detection in combination with the proven concept of using single mode, polarization maintaining fibres for excitation. The latter ensures in combination with a diligent beam path design, that only a diffraction limited sample volume is illuminated. The photonic fibre on the other hand is ideally suited to design detection beam paths optimized for throughput while maintaining diffraction limited resolution as well as a level of confocality close to the limits of physics. The new alpha300, access300 and apyron system families all feature this new design and will be described in detail. Depth resolution as measured on suspended Graphene as well as measured on standard Si samples prove the afore mentioned high level of confocality. Additional measurements proving the lateral resolution (determined on isolated CNTs) as well as the sensitivity (i.e. shown by measurement of the 4th order of Si) recorded at exactly the same experimental settings will also be presented.

Using photonic fibres for detection allowed in addition the design of vastly improved spectrometers enabling very high spectral resolution at throughput levels of more than 60% including the loss by the grating. These spectrometers can cover wide spectral ranges or can be optimized for dedicated Raman detection ranges matching the peak quantum efficiencies of state-of-the art CCD cameras resulting in spectroscopic systems with the highest detection sensitivity. This new family of spectrometers will be introduced in detail and their performance illustrated using various examples from different fields of applications.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

A Novel Multivariate Spectral Searching Method

Jun Zhao

B&WTek, United States of America; junz@bwtek.com

A method for determining the likely composition of a sample is developed based on a novel variable reduction technique and multivariate statistical spectral analysis. The method comprises, obtaining a spectrum of the sample; Obtaining multiple spectra of one or more target materials; Pre-process the spectra; Providing a variable reduction means that combines certain contiguous spectral variables into a single variable; Determining an average spectrum and the statistic distribution of each of the target material in the reduced dimension; determining the likelihood the sample had the same composition of each of the target material; and displaying the list of the most likely target material to a user. The variable reduction method largely removes the high degree of correlation among the large number of spectral elements in the original space, and makes it possible to calculate the p-Value using the Hotelling T2 statistics.



MoA - O - 005: Non-Linear and Time Resolved Spectroscopy

Time: Monday, 15/Aug/2016: 11:00am - 12:40pm  ·  Location: Topázio Room
Session Chair: Paul Champion

This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

Snapshots of ultrafast processes in biomolecules and condensed matter in the light of Femtosecond Stimulated Raman Spectroscopy

Tullio Scopigno

University "Sapienza" Rome, Italy; tullio.scopigno@roma1.infn.it

Time Resolved Resonance Raman is a powerful technique to study photo-induced dynamics with structural sensitivity, whose time resolution has been improved over the years from microseconds to a few picoseconds. If a sharp spectral resolution (<15cm-1) is to be maintained, however, no further improvement of the time resolution (<1 ps) is obtainable with a traditional two beams pump-probe layout, due to the Fourier Transform limit. In recent years, Femtosecond Stimulated Raman Spectroscopy (FSRS) has been proposed as a possible way to "circumvent" the aforementioned time-bandwidth limitation, promising simultaneously high temporal precision and spectral resolution. I will present an account of recent results obtained in our group by developing a broadly tuneable FSRS setup, capable to explore resonance effects in diverse contexts. These include the visualization of energy flow in heme-proteins, the ultrafast light-induced modification of the exchange energy in a Heisenberg antiferromagnet, the reaction pathway upon photo-excitation of conjugated molecules. Emphasis will be given on how sub-ps snapshots with atomic resolution can be obtained under the constraint imposed by the Heisenberg principle.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Effect of Cholesterol on Lipid Bilayer Membranes Estimated with Picosecond Time-Resolved Raman Spectroscopy

Sho Kitamura, Tomohisa Takaya, Koichi Iwata

Gakushuin University, Japan; koichi.iwata@gakushuin.ac.jp

Cholesterol is a major constituent of biomembranes. The presence of cholesterol can alter the character of the biomembranes and therefore the mechanism of the chemical reactions that proceed there. We examine how cholesterol affects the energy transfer process in the lipid bilayer membranes by estimating the thermal diffusivity of the bilayer membranes. We solubilize trans-stilbene in single-layer liposomes formed by DPPC and photoexcite the trans-stilbene molecule to the S1 state with vibrational excess energy of approximately 3000 cm-1. The cooling process that follows the photoexcitation is monitored with picosecond time-resolved Raman spectroscopy. With the correlation between the cooling rate constant and the thermal diffusivity of the solvent known for ordinary solvents, we estimate that the thermal diffusivity of the liposome DPPC bilayer membrane with 30% cholesterol is larger than the thermal diffusivity of the same membrane without cholesterol.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Time resolved Resonance Raman studies of key inorganic transients in aqueous media

Ireneusz Janik, GNR Tripathi

Radiation Laboratory, University of Notre Dame, United States of America; ijanik@nd.edu

Time resolved Resonance Raman (TRRR) proven to be a very convenient technique in explanation of broad variety of free radical driven processes in aqueous media. The innovations in the pulse radiolysis setup with TRRR detection at the Notre Dame Radiation Laboratory allowed us to reduce the overall volume of the solutions required to perform typical pulse radiolytical TRRR studies and the signal collection times by three and four orders of magnitude, respectively. Such an extensive improvement have permitted to perform studies of reaction intermediates which were problematic earlier. Vibrational signatures of a number of key inorganic transients absorbing light in deep ultraviolet have been characterized for the first time. Experimental results and their implications to understanding the mechanistic transformations of exemplary nitrogen and oxygen containing intermediates like NO32-, N2O2- will be presented shortly. The nature of superoxide as well as carbon dioxide radical anion in water will be described in more detail.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Spectral watermarking approach to femtosecond Raman spectroscopy

Miroslav Kloz1,2

1Institu of Physcis AVCR v.v.i., Czech Republic; 2Free University Amsterdam; miroslav.kloz@eli-beams.eu

A new method for recording femtosecond Raman spectra was developed that dramatically improves and automatizes baseline problems. Instead of using a narrowband Raman source, the experiment is performed using shaping of a broadband source. This allows locking the signal into carefully crafted watermarks that can be recovered from measured data with high fidelity. The approach allows a direct recording of stimulated Raman signals with robust rejection of baselines and fixed-pattern-noise. The methodology is applicable to any Raman experiment but primarily targets Femtosecond Stimulated Raman spectroscopy (FSRS) where a lack of robust methods for parasitic signal rejection has been a major obstacle in the practical development of the field in the last decade. The delivered improvement in FSRS experiments was demonstrated by recording evidence that the so-called S* state of carotenoids in solution corresponds to the optically forbidden S1 state of a sparsely populated carotenoid conformation.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Frequency- and Time-domain Studies of the Elementary Interaction of Organic Molecules and Metal Surfaces with Special Emphasis on Raman Spectroscopy

Arnulf Materny, Faezeh Mohaghegh, Alireza Mazaheri Tehrani, Patrice Donfack, Tahir Zeb Khan

Jacobs University Bremen, Germany; a.materny@jacobs-university.de

Vibrational and electronic properties of molecules adsorbed to metals can be strongly influenced by the interaction between metal electrons and the electronic system of the molecules. This is well known from the surface-enhancement (SE) observed for Raman scattering when nanoparticles of coin metals are added to a sample containing a low concentration of specific molecules. There, besides the pure enhancement of the Raman scattering also changes in the Raman spectra can be observed. For a better understanding of this so-called chemical or electronic SE mechanism of the SE Raman scattering (SERS), different experiments have been performed, which try to combine the energetic with the dynamic picture of this mechanism.



MoA - O - 006: Solid State

Time: Monday, 15/Aug/2016: 11:00am - 12:40pm  ·  Location: Safira Room
Session Chair: Carlos William Paschoal

This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

Raman and IR studies of multiferroic metal formates templated by protonated amines

Miroslaw Robert Maczka, Aneta Ciupa, Maciej Ptak, Jerzy Hanuza

Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Poland; m.maczka@int.pan.wroc.pl

Metal-organic frameworks (MOFs) containing formate ligands received a lot of attention in recent years since the HCOO- ion is capable of mediating ferro- or antiferromagnetic coupling between metal ions. Due to this feature, many formates exhibit interesting magnetic properties. Some of them also undergo structural phase transitions and discovery of the first multiferroic formate, [(CH3)2NH2][Mn(HCOO)3], promoted broad interest in the properties and phase transition mechanism in these compounds as well as led to many efforts to synthesize novel metal formates templated by protonated amines.

Herein, we report temperature-dependent Raman and IR studies of a number of heterometallic and mixed-valence formates crystallizing in niccolite-type structure as well as multiferroic DMMn doped with Cr(III) crystallizing in the perovskite-type structure. We will show that vibrational studies provide very useful information on their local structure, mechanism of the structural phase transitions occurring in these compounds and their chemical compositions.


This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

Spin-Phonon Coupling: A Probe of Magnetism through Lattice Vibrations

Eduardo Granado

University of Campinas - UNICAMP, Brazil; egranado@ifi.unicamp.br

Normal modes of vibration may produce a modulation of the interatomic exchange energy in magnetic materials, leading to phonon anomalies at temperatures where the spin correlations set in. This effect has been used as a probe of short-range spin correlations and the microscopic nature of exchange coupling of materials of interest. In this talk I will review some examples of successful application of this technique, including LaMnO3 and CaMnO3 manganites, RMn2O5 multiferroics, Ba2FeReO6 and Sr2FeCrO6 double perovskites and materials showing frustrated and/or low-dimensional magnetism.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Structural and magnetic phase transitions in multiferroic rare-earth tetraborate crystals

Alexander S. Krylov, Evgeniya Moshkina, Svetlana Sofronovа, Irina Gudim, Vladislav Temerov, Alexander Vtyurin

L.V.Kirensky Institute of Physisc SB RAS, Russian Federation; shusy@iph.krasn.ru

Crystals of the RFe3(BO3)4 family (R is rare earth ion) were reported to possess multiferroic features, demonstrating both structural and magnetic phase transitions, where transition points may be varied by rare earth composition. In this work we study two rare-earth systems - Ho1–xNdxFe3(BO3)4 and Sm1–yLayFe3(BO3)4 single crystals and solid solutions. Temperature measurements were performed in the temperature range 10–400 K. The aim of this study is to investigate possible existence of a soft mode related to structural order parameter and effects of magnetic transitions on Raman spectra. Analysis of vibrational spectra and its numerical simulation demonstrate that bigger cell volume of Nd-containing solid solutions provides bigger displacements of oxygen ions in a BO3 groups below the Neel temperature that results in stronger magnetoelastic interactions. This leads to the appearance of additional lines in the Raman spectra and rapid increase of their intensity with increasing magnetic order.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Dinamic nematic effects observation in the oxypnictide compound LaFeAsO observed by Raman scattering

Ulisses Ferreira Kaneko1, Paulo Gomes Freitas2, Ali Francisco Garcia Flores1, Gaston E. Barberis1, David Vaknin3, Eduardo Granado1

1UNICAMP, Brazil; 2UFG, Brazil; 3Iowa State University, USA; ulisseskaneko@gmail.com

The effects of the tetragonal-orthorhombic and magnetic ordering transitions on the nematic phase of LaFeAsO single crystal are investigated by Raman scattering. Below ~150 K a drastic change is observed in the polarization selection rules of the phonon mode around 161 cm-1 (Fig. 1), which is related to a shearing of the unit cell axes that leads to the formation of long-range orthorhombic domains below Tp ~ 148 K [1] due to magneto-elastic effects coupled to the electronic nematic phase [2]. This can be explained from an electronic nematic order point of view [2]. In addition we observe significant quasi-elastic contribution above ~100K, that in our view signals nematicity. The quasi-elastic scattering persists on warming up to ~200 K exhibiting a minimum in the electronic nematic phase that divides two maxima at structural transition, Tp~150 K and at the magnetic ordering TN~140 K.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Self-healing polymers studied by Raman spectroscopy and two-dimensional correlation analysis

Robert Geitner1, Julia Kötteritzsch2,3, Michael Siegmann1, Thomas Bocklitz1,4, Martin Hager2,3, Ulrich Schubert2,3, Stefanie Gräfe1, Benjamin Dietzek1,3,4, Michael Schmitt1, Jürgen Popp1,3,4

1Friedrich-Schiller University and Abbe Center of Photonics Jena, Germany; 2Laboratory for Organic and Macromolecular Chemistry (IOMC) Jena, Germany; 3Jena Center of Soft Matter (JCSM), Germany; 4Leibniz Institute for Photonic Technology (IPHT) Jena, Germany; robert.geitner@uni-jena.de

Material lifetime is an important topic in modern material science. Material failure can lead to accidents and high repair costs to restore the original material properties. One possible approach to increase the lifetime of materials is self-healing.

Raman spectroscopy can be used to monitor and understand the self-healing process of polymers on a molecular level. Every healing reaction or interaction is accompanied by specific molecular structure changes, which can be probed by Raman spectroscopy.

Here, we summarize our recent Raman studies to characterize different self-healing copolymers, which utilize Diels-Alder reactions between maleimide and furan groups as well as between anthracene and C60-fullerene molecules. To highlight the subtle spectral changes due to the Diels-Alder self-healing process we combined Raman spectroscopy with two-dimensional (2D) correlation analysis. Overall, it will be shown that 2D Raman correlation analysis is a powerful technique to characterize self-healing reactions on a molecular scale.



MoP - O - 001: SERS and Applications

Time: Monday, 15/Aug/2016: 2:30pm - 4:00pm  ·  Location: Ruby Room
Session Chair: Alexandre Brolo

This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

On the chemical and biochemical origins of the SERS spectra of bacteria

Lawrence Ziegler

Boston University, United States of America; lziegler@bu.edu

The vibrational features in the 785 nm excited SERS spectra of bacterial cells on Au nanostructured substrates are due to different relative amounts of six purines: adenine, hypoxanthine, xanthine, guanine, uric acid and AMP. Isotopic labeling, comparison of bacteria cellular and supernatant SERS spectra and fits of the observed SERS spectra to a linear combination of these six purines are conclusive evidence that these bacterial SERS spectra are due to these purine bases. The biochemical origins of this metabolic footprint is the rapid onset of the starvation response of bacterial cells. These purine signatures vanish when a carbon source such as glucose is added to this environment. The absence or presence of different degradation/salvage enzymes in the metabolism pathways of these organisms thus plays a central role in determining the bacterial specificity of these SERS signatures which is the basis for the use of SERS as a rapid bacterial diagnostic.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Surface-enhanced Raman Scattering Identifies Biofilms of Clinically Important Microorganisms

Seda Kelestemur, Mustafa Culha

Yeditepe University, Turkey; mculha2@gmail.com

Microorganisms secret a complex extracellular matrix composed of polysaccharides, lipids, protein, genetic materials and humic substances, which is called biofilm, to protect themselves from external threats. A better understanding of biofilm formation can have a major impact in several fields including food industry and medicine. Therefore, a better understanding of biofilm formation at molecular level is very important to develop approaches to prevent biofilm formation by pathogenic microorganisms. In this study, we demonstrate the monitoring biofilm formation of clinically important microorganisms; Pseudomonas aeruginosa, Staphylococcus epidermidis and Candida albicans, and the detection of their biofilms using surface-enhanced Raman scattering (SERS). The metabolic activities of microorganisms during biofilm formation on 2D and 3D substrates under external stress such as heat and antibiotic exposure are also monitored through mapping the area where a droplet of colloidal AgNP suspension is placed. The discrimination of the characteristic metabolic activities of the microorganisms was also demonstrated.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Controlling adsorption interactions of biomolecules on silver and gold surfaces investigated by SERS spectroscopy

Antonio Carlos Sant'Ana, Aline Luciano Filgueiras, Bruno Guilherme daFonseca

Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brazil; antonio.sant@ufjf.edu.br

In this work we have investigated oligopeptides and antibiotics adsorbed on the surfaces of silver and gold nanoparticles, with the chemical interactions controlled by the surface modifiers mercaptoethanol and chloride ion.

The adsorption of L-Tryptophan (Trp) and 4 peptides: Trp-Gly, Ala-Trp, p-Glu-Lys-Trp-Ala-Pro (P5) and Trp-His-Trp-Leu-Gln-Leu (P6), on silver and gold surfaces modified or not by chloride ions, were investigated through surface-enhanced Raman scattering (SERS) spectroscopy. Trp preferably adsorbs through indolic nitrogen on gold surfaces and through COO- and NH3+ groups on silver surfaces.

The SERS spectra of the antibiotics aztreonam, metronidazole and tinidazole adsorbed on silver surfaces were obtained in the presence of 2- mercaptoethanol, as well as in the presence of polyvinylpyrrolidone and in absence of surface modifiers.



MoP - O - 002: Biological Applications

Time: Monday, 15/Aug/2016: 2:30pm - 4:00pm  ·  Location: Esmeralda Room
Session Chair: Janina Kneipp

This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Raman spectroscopy of transfusable red blood cells stored inside sealed plastic blood-bags

Chad G. Atkins1,2, Kevin Buckley1,6, Deborah Chen3,4, H. Georg Schulze1, Dana V. Devine3,4, Michael W. Blades2, Robin F. B. Turner1,2,5

1Michael Smith Laboratories, The University of British Columbia, Vancouver, Canada; 2Department of Chemistry, The University of British Columbia, Vancouver, Canada; 3Department of Pathology and Laboratory Medicine, The University of British Columbia, Vancouver, Canada; 4Centre for Blood Research, The University of British Columbia, Vancouver, Canada; 5Department of Electrical and Computer Engineering, The University of British Columbia, Vancouver, Canada; 6Nanoscale Biophotonics Laboratory, School of Chemistry, National University of Ireland, Galway, Ireland; catkins@chem.ubc.ca

Red blood cells (RBCs) are separated from (donated) whole blood, suspended in specially formulated additive solutions, and stored (at 4 °C) in polyvinyl chloride (PVC) blood-bags until needed for transfusion. These stored RBCs undergo biochemical changes that lower effectiveness of the transfusion, and such changes are known to vary in ways that are largely unpredictable based on donor characteristics. In this study, micro-Spatially Offset Raman Spectroscopy (µ-SORS) is used to probe, non-invasively, the biochemistry of RBCs inside sealed blood-bags. The retrieved spectra compare well with conventional Raman spectra (of sampled aliquots) and are dominated by features associated with hemoglobin. The data reveal interesting detail about the oxygenation-state of the stored cells themselves, namely that some blood-bags unexpectedly contain measurable amounts of deoxygenated hemoglobin after weeks of storage. The demonstration that chemical information can be obtained non-invasively using spectroscopy will enable new studies of RBC degeneration under normal storage conditions.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

SERS-based Multiplex Assay and Cellular Imaging

Jiming Hu

Wuhan University, China, People's Republic of; jmhu@whu.edu.cn

Surface-enhanced Raman scatter (SERS) technique has been fully demonstrated to be highly suitable for multi-targeting assay and cellulr imaging since due to its high sensitivity and multiplex detection capability. Herein, we describe recent advances in this domain including the design and synthesis of SERS substrates and Raman tagging molecules, label-/separation-free SERS assay and in vitro/vivo SERS cellular imaging in our group. Especially, a focusing introduction is given on novel SERS enabled microdevices for micro-area sampling and quantitative, separation-free detection of multiple organic/inorganic residues, and a cluster of novel C≡C reporting SERS tags competent in single band-based multicolor cellular imaging and multiplex biochemical sensing without any optical interference.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Investigation of squalenoylated doxorubicin interactions within living cancer cells using near infrared Raman microspectroscopy

Hassan Rammal1,2, Simona Mura3, Andrey Maksimenko3, Franco Dosio4, Barbara Stella4, Pierre Jeannesson2, Olivier Piot2, Patrick Couvreur3, Hamid Morjani2, Abdelilah Beljebbar2

1MEDyC CNRS UMR7369, Université de Reims, Faculté de Pharmacie, Reims, France; 2EA 4691 BIOS, Université de Reims, Faculté de Pharmacie, Reims, France; 3Institut Galien CNRS UMR8612, Université Paris Sud, Faculté de Pharmacie, Châtenay-Malabry, France; 4Dipartimento di Scienza e Tecnologia del Farmaco, Università degli Studi di Torino, Turin, Italy; olivier.piot@univ-reims.fr

Raman spectroscopy was used to study the effect of chemotherapeutic agents Doxorubicin (DOX) and squalenoyl doxorubicin (SQ-DOX) in living cells. The antitumor activity of DOX was attributed to the intercalation of the chromophore between the base pairs of DNA. SQ-DOX has emerged as a novel anticancer agent with more sufficient anticancer activity and less side effects as compared to DOX. The aim of this study was to characterize the structure of drug-DNA complexes in order to provide a possible explanation of the differences in the clinical activity of the two drugs. Our results demonstrated the potential of Raman spectroscopy to localize the DOX and SQ-DOX in cytoplasm and nucleus. Indeed, the DOX was only detected in the nucleus while the SQ-DOX was distributed in the two different subcellular regions with high concentration.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Chip-based Pathogen Detection and Drug Monitoring using Raman Spectroscopic techniques

Karina Weber1,2,3, Susanne Pahlow2,3, Izabella Hidi2,3, Anna Mühlig1,3, Martin Jahn2,3, Sandra Kloß2,3, Stephan Stöckel2,3, Petra Rösch2,3, Dana Cialla-May1,2,3, Jürgen Popp1,2,3

1Leibniz Institute of Photonic Technology e.V. Jena, Germany; 2Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich-Schiller-University Jena, Germany; 3InfectoGnostics Forschungscampus Jena e.V., Zentrum für Angewandte Forschung, Germany; karina.weber@leibniz-ipht.de

Huge demands for modern analytical approaches for an on-site testing allowing for a fast and reliable diagnosis followed by a personalized treatment decision exist. In this context, Raman spectroscopic approaches in combination with chip based sampling strategies are very promising.

Within this contribution, we will introduce a Raman compatible chip-based isolation strategy of microorganisms from complex media applying capture molecules (such as antibodies, pyoverdine). The so isolated bacterial cells gave typical bacterial Raman spectra, which could be automatically identified via chemometric procedures. The second part of this contribution reports about a Lab-on-a-Chip-SERS platform for high-throughput and reproducible measurements towards drug monitoring. Exemplarily, the detection of methotrexate within a blood plasma matrix and levofloxacin within the matrices of artificial urine as well as patient samples will be discussed. A quantitative detection down to the medical-relevant concentration range is achieved for both tested analytes, which illustrates the potential of the proposed method.



MoP - O - 003: Raman Imaging

Time: Monday, 15/Aug/2016: 2:30pm - 4:00pm  ·  Location: Ametista Room
Session Chair: Dongho Kim

This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

Spectroscopic Imaging of 3D Molecular Orientation by Polarization Broadband CARS

Young Jong Lee

National Institute of Standards and Technology, United States of America; yjlee@nist.gov

A new optical method is discussed on how to determine three-dimensional (3D) molecular orientation by concurrently analyzing multiple Raman polarization profiles [1]. Conventional approaches to polarization Raman spectroscopy [2] are based on single peaks, and their 2D-projected polarization profiles are limited in providing 3D orientational information. Our new method analyzes multiple Raman profiles acquired by a single polarization scanning measurement of broadband coherent anti-Stokes Raman scattering (BCARS). Because the analysis uses only dimensionless quantities (intensity ratios and phase difference) between multiple profiles, the results are not affected by sample concentration and the system response function. We describe how to determine the 3D molecular orientation for two simplified model cases and discuss the effect of orientational broadening. We find that in the presence of broadening we can still determine the mean 3D orientation angles and, furthermore, the degree of orientational broadening.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Spectroscopy and Imaging Two Dimensional Materials with Nonlinear-Optics and Nonlinear-Raman Scattering

Leandro Malard1, Lucas Lafetá1, Alisson Cadore1, Thiago Grasiano1, Kenji Watanabe2, Takashi Taniguchi2, Leonardo Campos1, Ana Maria de Paula1, Ado Jorio1

1Departamento de Física, Universidade Federal de Minas Gerais, Brazil; 2National Institute for Materials Science, Tsukuba, Ibaraki, 305-0044 Japan; lmalard@fisica.ufmg.br

In this work we will show some of our progress for imaging two dimensional materials by non linear optics and Stimulated Raman Scattering (SRS) and with coherent anti-stokes spectrocopy (CARS). We will show the use of second harmonic generation to image and study single layers of two dimensional MoS2. We also show the study of CARS in graphene and hexagonal boron-nitride. For the case of h-BN was observed an increase in the intensity of anti-Stokes signal when the energy difference between the pump laser and Stokes is equal to the phonon energy of h-BN. However, in graphene the signal was decreased when the energy difference is equal to the phonon energy. We will address the causes for the observation of this phenomenon based on different electronic structures of these two materials. Finally, we will discuss the application of SRS imaging in h-BN in order to identify these layers.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Combined surface enhanced Raman and hyper-Raman hyperspectral imaging for bio-applications

Zsuzsanna Heiner1,2, Marina Gühlke2, Fani Madzharova2, Vesna Zivanovic1,2, Janina Kneipp1,2

1SALSA School of Analytical Sciences Adlershof, Humboldt Univerität zu Berlin, Germany; 2Department of Chemistry, Humboldt Universität zu Berlin, Brook-Taylor-Str.2, 12489 Berlin, Germany; heinerzs@hu-berlin.de

We investigated whether combined surface-enhanced Raman scattering (SERS) and hyper-Raman scattering (SEHRS) spectroscopy based multivariate analysis can be used to determine the distribution of structurally almost identical molecules. First, we mapped the distributions of malachite green and crystal violet dyes. To demonstrate the potential of this approach for multiplex imaging of complex systems, we applied combined SERS and SEHRS mapping to live cells and successfully located spectrally similar reporter molecules. Because SEHRS is very sensitive to molecule-nanoparticle interaction and offers complementary structural information, the application of combined SERS and SEHRS hyperspectral imaging in live cells opens up new perspectives in all-optical nanosensing.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

CARS/SHG/TPEF multimodal microscopy towards intraoperative frozen section analysis

Michael Schmitt1, Olga Chernavskaia1,2, Sandro Heuke1,2, Fisseha Bekele Legesse1,2, Thomas Bocklitz1,2, Tobias Meyer1,2, Juergen Popp1,2

1Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich-Schiller University Jena, Germany; 2Leibniz Institute of Photonic Technology Jena, Germany; m.schmitt@uni-jena.de

An important unsolved medical need placed on pathological diagnostics is a reliable, fast and safe intraoperative tumor margin detection and the extraction of reliable disease markers from frozen tissue sections. Here, we demonstrate that the combination of multiplexed coherent anti-Stokes Raman scattering (CARS), with two-photon-excited autofluorescence (TPEF) and second harminic generation (SHG) allows for the detection of characteristic structures and the accompanying molecular changes of widespread diseases, particularly of cancer. The potential of this multimodal imaging approach together with advanced image analysis routines to overcome current limitations of frozen section analysis with respect to achieving a reliable intraoperative tumor margin detection will be highlighted. We will introduce a compact CARS/SHG/TPEF multimodal nonlinear microscope for use in clinics. Overall, the presented examples demonstrate that CARS/TPEF/SHG multimodal imaging provides a sensitive and selective tool to potentially complement established clinical pathological diagnostic tools and therefore to solve challenges currently faced by clinical pathology.



MoP - O - 004: Art and Archeology

Time: Monday, 15/Aug/2016: 2:30pm - 4:00pm · Location: Topázio Room
Session Chair: Thiago Sevilhano Puglieri

This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Characterization of gothic painting layers containing copper pigments by means of FTIR and Raman imaging spectroscopy

Andrey G.G. Oliveira1, Kinga Czarnecka1, Zofia Kaszowska2, Kamilla Malek1

1Faculty of Chemistry, Jagiellonian University, Poland; 2Faculty of Conservation and Restoration of Works of Art, Jan Matejko Academy of Fine Arts in Krakow, Poland; malek@chemia.uj.edu.pl

The complementary Fourier Transform Infrared (FTIR) and confocal Raman spectroscopies have been successfully employed on the chemical characterization of artworks containing blue layers. These non-destructive techniques allows not only the identification of pigments, binders, additives, fillers and degradation compounds that are important for restoration and preservation of cultural-heritage objects but also to obtain information of the chemical distribution through the painting layers. Overall, the findings presented here support the concept of using both complementary spectroscopy techniques for a full and precise chemical characterization of gothic blue paintings.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

On the enhanced stability of indigo in Maya blue simulants

Nathália D'Elboux Bernardino1,2, Vera R. Leopoldo Constantino1, Terry L. Gustafson2, Samantha Brown-Xu2, Dalva L. Araújo de Faria1

1Universidade de São Paulo; 2The Ohio State University; nathaliadelboux@hotmail.com

In the present work, Maya blue (MB) simulants were investigated by resonance Raman spectroscopy and time resolved spectroscopy (Time Resolved Infrared - TRIR and Transient Absorption - TA) in order to shed light into the factors affecting the pigment stability.

The results from Raman spectra using 457.9 nm showed that, different from what is found in the literature, dehydroindigo is not formed (at detectable levels) in the MB simulants. Moreover, the Raman spectra obtained at various λ clearly showed that indigo is interacting with coordinated water molecules inside the micropores through hydrogen bond.

Time resolved IR measurements carried out on indigo (in deuterated-DMSO solution) and ind-paly heated at 130 °C showed that the interaction with the clay causes a much more efficient decay to the ground state, which is likely to be the responsible for the enhanced photochemical stability of indigo in the Maya blue simulant.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Preliminary results of chemical and physical evidence of heating treatment of the Middle Stone Age ochre from Rose Cottage and Sibudu Caves, South Africa

Marine, Claude-Alice Wojcieszak1, Tammy Hodgskiss1, Lyn Wadley1, Philippe Colomban2

1Evolutionary Studies Institute, University of the Witwatersrand, South Africa; 2MONARIS, Université Pierre et Marie Curie; marine.wojcieszak@gmail.com

Two significant and long Middle Stone Age sequences are covered in Rose Cottage and Sibudu Caves which yielded a large quantity of ochre pieces. A physico-chemical characterisation is required to add value to the prior study of ochre use traces. This project aims to apply a multi-analytical approach (including Raman spectroscopy, FT-IR, XRD, SEM and XRF) to characterise ochre pieces from both archaeological sites. Physico-chemical investigations will help us to gain a deeper understanding of changing ochre collection, preparation, and use through time. Part of the preparation phase may have involved heat treatment to alter the colour and possibly the mechanical properties of the ochre. This possibility will be investigated by reproducing experimental heat treatment with geological pieces. Heat treatment would be an indicator of advanced practices; this research will help to gain deeper understanding of behaviour, customs and cognition of Middle Stone Age people.



MoP - O - 005: Carbon Materials

Time: Monday, 15/Aug/2016: 2:30pm - 4:00pm  ·  Location: Safira Room
Session Chair: Cristiano Fantini

This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

Tunable Filter-based Raman Excitation Mapping of Pure Single-Wall Carbon Nanotubes

Paul Finnie

National Research Council Canada; Paul.Finnie@nrc-cnrc.gc.ca

Characterization is a bottleneck in the development of improved purified single wall carbon nanotube (SWCNT) materials, and tunable Raman spectroscopy can help. Here, experimental Raman excitation maps (REMs) are obtained from a custom tunable filter Raman spectroscopy (TFRS) system. Maps are obtained from unsorted SWCNTs, highly purified metallic SWCNTs and highly purified semiconducting SWCNTs. The maps have good signal-to-noise and cover broad excitation ranges. The REMs show the structure of bands such as the RBM, G-, G+ and 2D, as well as less prominent ones, and resonant excitation profiles (REPs) are obtained. Such maps are useful for the assessment of purity in the current generation of SWCNT samples. They help overcome ambiguity in fixed wavelength Raman spectroscopy data, and can be used to support fixed wavelength purity assessment protocols. Some challenges arising in nanocarbon metrology and Raman metrology will be shown, and emerging opportunities will be highlighted.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Collapse of double-walled carbon nanotubes: dependence on the diameters of the inner and the outer shells

Rafael Silva Alencar1,2, Abraão Cefas Torres Dias1,2, Tiago Frederico Teixeira Cerqueira2,3, Wenwen Cui2, Silvana Botti2,4,5, Miguel Alexandre Lopes Marques2,6,5, Alexander V. Soldatov2, Odair Pastor Ferreira1, Christophe Laurent7, Alicia Weibel7, Denis Machon2, Antonio Gomes de Souza Filho1, Alfonso San-Miguel2

1Departamento de Física, Universidade Federal do Ceará, Fortaleza, Ceará, 60455-900 Brazil.; 2Université de Lyon, F-69000 Lyon, France and Institut Lumière Matière, CNRS, UMR 5306, Université Lyon 1, F-69622 Villeurbanne, France; 3Institut für Festköpertheorie und optik Friedrich-Schiller, University of Jena, Jena, Germany; 4Institut für Festköpertheorie und optik Friedrich-Schiller, University of Jena, Max-Wien-Platz 1, 07743 Jena, Germany; 5European Theoretical Spectroscopy Facility; 6Institut für Physik Martin-Luther-Universität Halle-Wittenberg, D-06099 Halle, Germany; 7CIRIMAT, Université Paul Sabatier et CNRS, Toulouse, France.; rafael_alencar@fisica.ufc.br

High pressure resonant Raman experiments were been performed in Double Walled Carbon Nanotubes (DWCNTs) having average inner (din) and outer (dout) diameters of 1.5 nm and 2.0 nm, respectively. Upon increasing pressure, changes in the G-band frequency vs. pressure plot and the disappearance of the radial breathing modes (RBMs) between 2 GPa and 5 GPa indicate the beginning and ending of the radial collapse of the nanotubes. Density Functional Theory Tight-Binding calculations were performed to investigate the pressure response in respect to diameter in DWCNTs. The results shown that the collapse pressure (Pc) for DWCNTs follows a d-3in law, in excellent agreement with the experimental results. The Pc dependence on number of tube-walls and on the inter-wall distance is also investigated.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Raman spectroscopy study of suspended graphene submitted to tip induced strain

Cassiano Rabelo1, Emil Sandoz-Rosado2, Ado Jorio3

1Programa de Pós-Graduação em Engenharia Elétrica, Universidade Federal de Minas Gerais; 2U.S. Army Research Laboratory; 3Departamento de Física, Universidade Federal de Minas Gerais; cassianorabelo@ufmg.br

In this work, we present Raman spectroscopy results obtained from measuring the mechanical properties of suspended graphene with in situ spectroscopy and nano-manipulation. The nano-manipulation procedure is performed through the use of a custom-built atomic force microscope (AFM) scanhead, used to produce tip induced strain.


This contribution has been accepted as a 15 minutes oral presentation.

Quantification of Defects in Single-wall Carbon Nanotubes

Jana Kalbacova1,2, Elias Garratt3, Raul D. Rodriguez1,2, Angela R. Hight Walker3, Kevin A. Twedt3,4, Jeffrey A. Fagan3, Jabez J. McClelland3, Babak Nikoobakht3, Dietrich R.T. Zahn1,2

1Semiconductor Physics, Technische Universität Chemnitz, 09107 Chemnitz, Germany; 2Center for Advancing Electronics Dresden (cfaed), Technische Universität Chemnitz, 09107 Chemnitz, Germany; 3National Institute of Standards and Technology, Gaithersburg, MD 20899, USA; 4Maryland Nanocenter, University of Maryland, College Park, MD 20742, USA; jana.kalbacova@physik.tu-chemnitz.de

Carbon nanotubes are no longer only a subject of academic studies but are widely used in technological applications. For this purpose, it is essential to understand the different types of defects and be able to quantify them. In this work, we applied a systematic approach to quantitatively evaluate defects from the intensity ratios of the characteristic Raman peaks. Vacancy-like defects were created by two types of focused ion beams (Li+ and Ga+) with ion fluences tuned over five orders of magnitude from 3∙1010 ions/cm2 to 1015 ions/cm2. Semiconducting and metallic single-wall carbon nanotubes thin films (~ 10 nm) were characterized by Raman spectroscopy with two laser lines (2.41 eV and 1.96 eV) to match the respective nanotube resonance conditions. The defects were assessed from the D/G and D/G’ intensity ratios. Based on the measured Raman intensity ratios and the calculated amount of defects created by the respective

TuA - O - 001: Plenary Session

Time: Tuesday, 16/Aug/2016: 8:50am - 10:30am  ·  Location: Ruby Room
Session Chair: Carlos Lenz Cesar

Stimulated Raman scattering microscopy: Label-free vibrational imaging for biology and medicine

Xiaoliang Sunney Xie

Harvard University, Department of Chemistry and Chemical Biology, USA; xie@chemistry.harvard.edu

Stimulated Raman scattering (SRS) microscopy is a label-free and noninvasive imaging technique using vibration spectroscopy as the contrast mechanism. Recent advances have allowed significant improvements in sensitivity, selectivity, robustness, and cost reduction, opening a wide range of applications. This is particularly relevant in biology since SRS microscopy does not affect cell function, and is best suited for imaging small metabolite molecules. For medicine, SRS microscopy provides instant tissue examination without the need of previous histological staining procedures.


Raman spectroscopy – the missing “magic bullet” to solve unmet medical needs!?

Juergen Popp1,2

1Leibniz Institute of Photonic Technology e.V., Germany; 2Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich-Schiller University Jena, Germany; juergen.popp@ipht-jena.de

In this presentation, we will address the potential and also limitations of Raman approaches for the benefit of the clinic, i.e. with respect to advancing them towards routine clinical application. We particularly focus on the diagnosis and therapy of infectious diseases and cancer, since these types of diseases as mentioned above represent unmet medical needs with respect to diagnosis and therapy. We will show that Raman spectroscopy holds great promise as point-of-care approach for the fast identification of pathogens, their antibiotic resistances and the specific host. Furthermore, it will be shown that the combination of linear and non-linear Raman approaches with other spectroscopic technologies provides a sensitive and selective tool to potentially solve challenges currently faced by clinical pathology.



TuA - O - 002: Plenary Session

Time: Tuesday, 16/Aug/2016: 11:00am - 11:50am  ·  Location: Ruby Room
Session Chair: Alejandro Pedro Ayala

Raman Optical Activity Comes of Age

Laurence David Barron

University of Glasgow, United Kingdom; laurence.barron@glasgow.ac.uk

Raman optical activity (ROA) provides complete vibrational optical activity spectra of chiral molecules, and molecules in magnetic fields, by means of a circular polarization-dependence of Raman scattering. Natural ROA probes molecular chirality; magnetic ROA probes magnetic structure. ROA can be applied to a vast range of molecular structures, from paramagnetic inorganic molecules and small chiral organics, to supramolecular structures and large biomolecules including intact viruses. The first observations of genuine ROA, published in 1973 amid much controversy, constituted the first observations of vibrational optical activity of molecular origin. Thanks to subsequent developments in instrumentation and theory, ROA is now a powerful chiroptical technique for addressing problems at the forefront of physics, chemistry and biomolecular science. Quantum-chemical simulations of measured ROA spectra can provide the complete three-dimensional solution structures of chiral molecules, including smaller proteins. This talk will present a review of ROA from first observations to current applications.



WeA - O - 001: Plenary Session

Time: Wednesday, 17/Aug/2016: 8:50am - 10:30am  ·  Location: Ruby Room
Session Chair: Marcos A Pimenta

Raman spectroscopy of atomic layer materials

Riichiro Saito1, Eddwi H. Hasdeo1, Yuki Tatsumi1, Ahmad R. T. Nugraha1, Huaihong Guo2, Teng Yang3, Mildred S. Dresselhaus4,5

1Tohoku University, Japan; 2College of Sciences, Liaoning Shihua University, Fushun 113001, People’s Republic of China; 3Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, People’s Republic of China; 4Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA; 5Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA; rsaito@flex.phys.tohoku.ac.jp

In this presentation, we overview our recent work of Raman and optical properties of twisted bilayer graphene (tBLG) [1], and transition metal dichalcogenides (TMD) [2-4]. Raman spectroscopy has been widely used for characterizing the number of atomic layers, twisting angle in tBLG [1] and electronic structure through the resonance Raman processes. In two dimensional (2D) materials, the joint density of states (JDOS) is singular logarithmically as a function of laser excitation energy (EL). Thus we expect a significant enhancement of Raman intensity for particular EL. In the hexagonal lattice, since the electronic energy dispersion becomes flat in the k space near the M point (center of hexagonal edge of the Brillouin zone), most of the singular JDOScorrespond to the optical transitions excited near the M point. Then the photo-excited electron near the M point can be scattered from one M point to other M points in the Brillouin zone by electron-phonon interaction [2]. This situation tells us that second order Raman processes with so-called double resonance Raman processes occurs by emitting the M point phonon [3]. We assigned many weak Raman spectra of TMD materials to the M point phonon modes by double resonance Raman spectra, by using ultra-violet light source. [3,4]

References:
[1] H. B. Ribeiro, K. Sato, G.S.N. Eliel, E.A.T. de Souza, Chun-Chieh Lu, Po-Wen Chiu, R. Saito, M.A. Pimenta, Carbon, 90, 138-145, (2015).
[2] H. Guo, T. Yang, M. Yamamoto, L. Zhou, R. Ishikawa, K. Ueno, K. Tsukagoshi, Z. Zhang, M.S. Dresselhaus, and R. Saito, Phys. Rev. B 91, 205415, (2015).
[3] H.L. Liu, H. Guo, T. Yang, Z. Zhang, Y. Kumamoto, C.C. Shen, Y.T. Hsu, R. Saito, S. Kawata, Phys.
Chem. Chem. Phys., 17, 14561 (2015).
[4] R. Saito, A. R. T. Nugraha, E. H. Hasdeo, S. Siregar, H. Guo, T. Yang, Phys. Stat. Solidi (B), 252, 2363 (2015).



Surface-enhanced Raman scattering in carbon nanostructures

Stephanie Reich

Freie Universität Berlin, Germany; reich@physik.fu-berlin.de

Surface-enhanced Raman scattering (SERS) describes the giant enhancement of the Raman cross section close to a metal surface. SERS can detect single molecules by optical spectroscopy. Its variant, tip-enhanced scattering (TERS) increases the resolution of Raman imaging down to the molecular limit. Here we present our results on SERS in graphene and carbon nanotubes. The enhancement is induced by the plasmons of well-controlled lithographically prepared gold nanodimers. Mechanically exfoliated graphene is deposited in a dry transfer process, whereas carbon nanotubes are placed by dieelectrophoresis. This setup allows to study the fundamental of SERS. We present results of the polarization and wavelength-dependence of plasmonic enhancement. The enhancement is extremely strongly localized in space (10 nm) and frequency (15 meV). Filled carbon nanotubes allow the placement of molecules in a well-characterized hotspot. We propose a description of SERS as a higher-order Raman process. The plasmon then forms an integral part of the light scattering process and gives rise to additional pair(s) of incoming and outgoing resonance. We discuss the consequences for SERS in molecules and artificial nanostructures and compare to our experimental findings.



WeA - O - 002: SERS and Biological Applications

Time: Wednesday, 17/Aug/2016: 11:00am - 12:40pm  ·  Location: Ruby Room
Session Chair: Lawrence Ziegler

This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

Surface enhanced hyper Raman and Raman scattering from biomolecules and cells

Janina Kneipp, Daniela Drescher, Tina Büchner, Vesna Živanović, Zsuzsanna Heiner, Marina Gühlke, Fani Madzharova

Humboldt-Universität zu Berlin, Germany; janina.kneipp@chemie.hu-berlin.de

Surface enhanced Raman scattering (SERS) and surface enhanced hyper Raman scattering (SEHRS) provide complementary vibrational information on organic molecules. In general, the high enhancement of hyper Raman scattering in the local optical fields of metal nanoparticles enables the observation of SEHRS signals at a sensitivity similar to two-photon fluorescence, and the probing of single cells. We present non-resonant SERS and SEHRS spectra of specific biomolecules and probe molecules inside and outside of cells that we have been discussing with the aim of better understanding spectra from complex biosamples. The two-photon excited spectra of are found to be very sensitive with respect to molecule-nanoparticle interactions that vary, e.g., with pH. As examples, we will present SEHRS spectra of nucleobases and data obtained with new composite nanostructures that have magnetic properties.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Gold nanoparticles with surface enhanced Raman scattering capability for the detection and treatment of glioblastoma tumours.

Carlyn Figueiredo1,2, Daniel Coluccia1, Alexandra Riemenschneider1, Amanda Luck1, Christian Smith1, James Rutka1,2

1Labatt Brain Tumour Research Centre, Hospital for Sick Children, Toronto, Canada; 2Laboratory Medicine and Pathobiology, University of Toronto, Canada; carlyn.figueiredo@mail.utoronto.ca

Glioblastoma multiforme (GBM) is the most common and lethal form of primary brain tumour, categorized by the WHO as a grade IV glioma. Given the infiltrative properties of GBM, novel strategies to visualize and target the cells responsible recurrence of GBM is urgently needed.We hypothesize that surface enhanced Raman scattering (SERS) gold nanoparticles (GNPs) can be specifically targeted towards GBM tumours in vivo. Furthermore, the addition of therapeutic moieties on the surface of these nanoparticles will provide methods to control tumour growth and proliferation. We demonstrate that SERS GNPs allow for easy in vitro and in vivo detection within U87 and U251 glioma tumour cell populations. Furthermore, we examined an erlotinib-gold conjugate depicting a C≡C peak, which also shows an enhanced effect in inhibiting U251 proliferation. Functionalized GNPs in conjunction with Raman spectroscopy will enhancing our capabilities to combat brain tumours without causing excessive damage to normal functioning tissue.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

SERS Detection of Biomolecules on Rationally Designed Metal Substrates

Marek Prochazka1, Lucie Stolcova2, Jan Proska2

1Charles University in Prague, Institute of Physics, Faculty of Mathematics and Physics, Czech Republic; 2Czech Technical University in Prague, Faculty of Nuclear Sciences and Physical Engineering, Department of Physical Electronics, Prague, Czech Republic; prochaz@karlov.mff.cuni.cz

In this contribution, we employed rationally designed gold substrates comprised of periodically modulated thin gold layers (FON) for SERS detection. FON was prepared by hexagonally ordered arrays of gold-coated PS nanospheres. Briefly, monodisperse PS nanospheres (107 nm in diameter) were deposited onto the water surface to form close-packed structures, and transferred onto silicon wafer. Then they were covered by thin layers (20 nm or 40 nm) of gold in magnetron sputter coater. Bare Au FONs were employed for detection of biomolecules: porphyrins (including protoporphyrin IX, marker in clinical diagnostics of cancer), nucleic acids, proteins and their components.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Raman and SERS help understand membrane composition of extracellular vesicles

Sebastian Wachsmann-Hogiu1,2, Zachary Smith1,3, Changwon Lee1, Tatu Rojalin1,4

1University of California Davis, United States of America; 2Intellectual Ventures Laboratory and Global Good, Belleview, WA, USA; 3University of Science and Technology of China, Hefei, Anhui, China; 4University of Helsinki, Helsinki, Finland; swachsmann@ucdavis.edu

In this work we evaluate the ability of Raman and SERS to characterize membrane composition of a class of nanoscale biological objects called extracellular vesicles.

Current analysis of extracellular vesicles focuses primarily on bulk analysis, where vesicle-by-vesicle variability cannot be assessed. In this study, we used Raman and SERS spectroscopy to study the chemical composition of single vesicles.

We trap single submicrometer extracellular vesicles with a focused laser beam and analyze their chemical composition. Particles extracted from the supernatant of 8 different cell lines, including normal and cancerous cells, were subjected to Raman analysis under the laser trap. The analysis of the spectra revealed clustering in 4 different groups that are not cell specific, but are mostly related to membrane composition. In addition, we deposited vesicles in micrometer nanobowl plasmonic structures and analysed them via SERS.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Confocal Raman microscopy for investigation of the nano-sized lipid particles penetration through the skin and their influence on intercellular lipid ordering ex vivo

Maxim Darvin1, Chunsik Choe1,2, Silke Lohan1, Martina Meinke1, Gaith Zoubari3, Roland Bodmeier3, Eckart Rühl4, Jürgen Lademann1

1Charité-Universitätsmedizin Berlin, Germany; 2Kim Il Sung University, Ryongnam-Dong, Taesong District, Pyongyang, DPR Korea; 3Freie Universität Berlin, Pharmazeutische Technologie, Institut für Pharmazie, Berlin, Germany; 4Physical and Theoretical Chemistry, Freie Universitaet Berlin, Berlin, Germany; maxim.darvin@charite.de

The penetration ability of nano-sized lipid particles (NLP: 117.5±2.8nm in size) in form of hydroxyethyl cellulose gel and base cream topically applied on porcine ear skin and their influence on the intercellular lipids (ICL) ordering in the SC were investigated ex vivo by analyzing the C-C skeleton stretching modes of ICL using confocal Raman microscopy 4 hours post application. The results show that the base cream is able to permeate through the stratum corneum (SC) barrier and influence the ordering of ICL in the whole SC making ICL less ordered. The NLP, however, saturate only the superficial skin layers and do not permeate through the SC barrier making the ICL more ordered in the corresponding depths.



WeA - O - 003: 2D Materials

Time: Wednesday, 17/Aug/2016: 11:00am - 12:40pm  ·  Location: Esmeralda Room
Session Chair: Ping-Heng Tan

This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

Raman-Active Phonons in Black Phosphorus

H. B. Ribeiro1, C. E. P. Villegas2, D. A. Bahamon1, A. H. Castro Neto3, E. A. T. de Souza1, A. R. Rocha2, M. A. Pimenta4, C. J. S. de Matos1

1MackGraphe, Mackenzie Presbyterian University, Brazil; 2Instituto de Física Teórica, Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Brazil; 3Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore, Singapore; 4Departamento de Física, UFMG, Brazil; cjsdematos@mackenzie.br

Exfoliated black phosphorus (BP) has recently emerged as a new layered crystal that due to its peculiar and anisotropic structure may have important applications in electronics, optoelectronics and photonics. BP exhibits a number of interesting Raman-active phonon properties, some of which will be addressed. Firstly, it will be shown that the fact that BP presents linear dichroism affects its polarized Raman spectrum, leading to Raman tensors with complex components. Experimental and theoretical work will also be described on the atomic structure and the behavior of phonons near different BP edges, via Raman spectroscopy and density functional theory calculations. Polarized Raman shows the appearance of new modes at the sample’s edges, and their spectra depend on the atomic structure of the edges (zigzag or armchair). Simulations confirm that the new modes are due to edge phonon states that are forbidden in the bulk, and originated from lattice termination rearrangements.


This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

Resonance Raman scattering in two-dimensional transition metals dichalcogenides

Cristiano Fantini, Bruno R Carvalho, Juliana A Martins, Rafael N Gontijo, Elena del Corro, Leandro M Malard, Ariete Righi, Marcos A Pimenta

UFMG, Brazil; fantini.cris@gmail.com

Single and few layers of MX2-type transition metal were investigated using many laser excitation energies. In the case of MoS2, changes in the wavenumbers of the first order A1g and E2g modes are associated with the number of layers. A continuous variation of the laser excitation energy in the range close to the direct band-gap reveals the presence of new dispersive features and the resonance behavior of, both first and second order, Raman modes. Exciton-phonon couplings are also observed by resonance Raman scattering. Results for different MX2-type materials and a comparative study of the resonance Raman process for these materials and graphene will be presented.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Two-dimensional Materials with Low Symmetry: Optical Anisotropy and Raman Enhancement

Lianming Tong

Peking University, China, People's Republic of; tonglm@pku.edu.cn

The crystalline structure of two-dimensional (2D) materials determines their intrinsic properties. 2D materials with low symmetry, including monoclinic black phosphorous (BP) and triclinic Rhenium Disulphide (ReS2), exhibit distinct anisotropy. The electronic, mechanical and optical properties strongly depend on the crystalline orientation. The anisotropy not only offers a new dimension in addition to the rich fundamental physical properties of 2D materials, but also implies novel optical and electronic applications.

We show the systematic investigations of the Raman scattering and polarized optical properties of 2D materials with low symmetry, such as BP and ReS2, including the development of rapid identification of crystalline orientation using angle-resolved Raman spectroscopy and polarized optical contrast imaging and spectroscopy, the anisotropic Raman enhancement, and the effect of optical birefringence in Raman scattering.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Intervalley Double-Resonance Raman Scattering in 2D MoS2

Bruno R. Carvalho1, Yuanxi Wang2, Sandro Mignuzzi3,4, Debdulal Roy3, Mauricio Terrones2,5, Cristiano Fantini1, Vincent H. Crespi2, Leandro M. Malard1, Marcos A. Pimenta1

1Departamento de Física, Universidade Federal de Minas Gerais, Caixa Postal 702, Belo Horizonte, 30123-970 Minas Gerais, Brazil; 2Department of Physics and Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, PA 16802, USA; 3National Physical Laboratory, Hampton Road, Teddington TW11 0LW, United Kingdom; 4Department of Physics, King's College London, Strand, London WC2R 2LS, United Kingdom; 5Department of Chemistry, Material Science and Engineering, The Pennsylvania State University, University Park, PA 16802, USA; brunorc@fisica.ufmg.br

Resonance Raman scattering provides a uniquely sensitive measurement of the electronic and phonon dispersion in layered materials. Recently, it has been demonstrated that resonance Raman spectroscopy can access the information about the strong exciton effects and their coupling with phonons in transition-metal dichalcogenides materials. Here we present an intervalley double-resonance Raman study in mono- and few-layered MoS2 structure, where we vary the incident photon across the A and B excitonic levels. We have observed that the resonance with the exciton level strongly enhances the second-order Raman features. At monolayer MoS2, a dispersion of the double resonant LA-phonon mode is observed. We demonstrated that the origin of the LA-phonon is near the K point. The Raman excitation profile shows that a phonon component can be suppressed due to the spin-polarized at the K (K’) valley in monolayer MoS2. Our results pave the way for the pursuit of the intervalley Raman scattering in transition-metal dichalcogenides.



WeA - O - 004: Raman Instrumentation & Industrial Applications

Time: Wednesday, 17/Aug/2016: 11:00am - 12:40pm  ·  Location: Ametista Room
Session Chair: S. L. Zhang

This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Handheld Probe for in situ Shifted Excitation Raman Difference Spectroscopy (SERDS) – Device and Performance

Martin Maiwald, Bernd Sumpf

Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Germany; Martin.Maiwald@FBH-Berlin.de

In this contribution a novel handheld probe for Raman spectroscopy and SERDS with an implemented dual-wavelength diode laser emitting at 785 nm is presented. The handheld probe has a dimension of 100 mm x 28 mm x 12 mm. The in-house developed and fabricated excitation light source provides an optical output power up to 120 mW ex probe. Two individually controllable excitation lines for SERDS show a spectral distance of 0.62 nm (10 cm-1) and a spectral width of < 11 pm (< 0.2 cm1) over the whole power range. Raman experiments using the SERDS probe and polystyrene (PS) as the test sample will be presented. Here, shot noise limited Raman spectra of PS with a signal-to-noise ratio of 115 are achieved. The results demonstrate the suitability of the compact probe for Raman spectroscopy and enable in situ SERDS investigations in real-world applications.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Dual-wavelength diode lasers with electrically adjustable spectral distance for shifted excitation Raman difference spectroscopy

Bernd Sumpf, Julia Kabitzke, Jörg Fricke, Peter Ressel, André Müller, Martin Maiwald, Günther Tränkle

Ferdinand-Braun-Institut, Germany; bernd.sumpf@fbh-berlin.de

Shifted excitation Raman difference spectroscopy (SERDS) is a powerful tool for the separation of weak Raman lines from fluorescence and background signals.

The spectral spacing between both wavelengths was chosen with respect to the full width at half maximum of Raman lines for most solid and liquid samples. However, the Raman band width can vary between different substances and an excitation light source with an adjustable spectral distance may be preferred.

In this contribution, 785 nm dual wavelength Y-branch DBR-RW lasers with an electrically adjustable spectral distance between both emission lines will be presented. The two wavelengths are addressed individually and the electrical adjustment of the wavelengths is performed by on-chip resistor heater elements. An overall tuning range of 30 cm-1 is achieved.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Analysis of Fault Gases Extracted from Transformer Oil Using Frequency-locking V-shaped Cavity Enhanced Raman Spectroscopy

Fu Wan, Weigen Chen, Pinyi Wang

Chongqing University, China, People's Republic of; fu.wan@hotmail.com

Highly accurate and sensitive measurement of multiple fault gases (CH4, C2H2, C2H4, C2H6, H2, CO, CO2, N2, and O2) is the key to diagnosing incipient transformer faults. To address the defects of the traditional method and achieve simultaneous and sensitive measurements, this study investigated the feasibility of gas measurement based on Raman spectroscopy. First, a frequency-locking V-shaped cavity enhanced Raman measurement system was designed and built up in laboratory. In addition, the Raman Stokes spectra for the nine gases were obtained. Then, the characteristic Raman Stokes spectrum for each gas species was determined according to the selection principle, and qualitative analyses of the nine fault characteristic gases were simultaneously performed. Furthermore, the minimum measurable concentration of each gas species was obtained through Raman measurements at different standard concentrations. The findings of this study lay the foundation for a new method for measuring fault gases extracted from transformer oil.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

True power-sharing multifocal Raman micro-spectroscopy from arbitrary ad hoc sampling locations for tissue diagnosis

Faris Sinjab, Kenny Kong, Ioan Notingher

School of Physics and Astronomy, University Park, University of Nottingham, Nottingham, NG7 2RD, UK; faris.sinjab@nottingham.ac.uk

We have developed a multi-focal Raman instrument for increasing the speed of selective/adaptive sampling Raman spectroscopy from multiple ad-hoc positions simultaneously. The instrument consists of two spatial light modulators (SLM), one for creating multiple laser excitation spots, and a second as a reflective pseudo-slit before the spectrometer entrance. Both of these SLMs are software controlled, allowing full automation for analysis of large structures such as biological tissue. We demonstrate the capability of this instrument on various samples, before combining with confocal autofluorescence for selective scanning Raman spectroscopy of skin tissue excised during surgery. It is shown that the multifocal Raman spectra are of sufficient quality to be used for cancer diagnosis.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Accurate Raman imaging of rough samples and/or those with complex surface topographies

Tim Batten1, Ken Williams1, Fabio Godoy2

1Renishaw plc, United Kingdom; 2Renishaw Latino Americana Ltda, Brazil; tim.batten@renishaw.com

In this work we compare and contrast the different solutions for maintaining focus and conducting Raman imaging on samples which are inherently rough and/or have complex surface geometries. We describe and illustrate the application of the new LiveTrack™ dynamic focus tracking technology, which not only provides in-focus Raman images of the most challenging samples but also topographic information, allowing three dimensional surface Raman images to be generated. We discuss and present data on a range of extremely difficult samples including:



WeA - O - 005: Non-Linear Raman Spectroscopy

Time: Wednesday, 17/Aug/2016: 11:00am - 12:40pm  ·  Location: Topázio Room
Session Chair: Wolfgang Kiefer

This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

Six Wave Mixing Coherent Anti-Stokes Raman Scattering in a Multimodal Microscopy Photonic Platform

V. B. Pelegati1, B. B. C. Kyotoku1, L. A. Padilha1, Carlos Lenz Cesar1,2

1IFGW, UNICAMP; 2Universidade Federal do Ceará, Brazil; lenz@fisica.ufc.br

We built a multimodal photonic platform including CARS and Six Wave Mixing CARS. Non-resonant background is the main issue for chemically selective imaging with CARS, a revolutionary microscopy technique. The fact that the coherent Non-Linear Optical process of CARS generate another beam at different wavelength makes the technique easy to implement, avoiding signals from incident lasers just with optical filters e no need for lock-in amplifier techniques. We decided to look for other coherent NLO processes with the same nice features of CARS. Experimentally we found a strong signal at a six wave-mixing process, which involves three photons of the pump beam and two of the Stokes beam, and showed that it was suitable to acquire laser scanning images. NLO spectroscopy literature called coherent process depending on Ip^3 and Is^2 leading to a signal at the frequency fsignal = 3 fpump -2 fstokes by sequential and parallel cascade CARS (CCARS), or Second Order CARS (SOCARS). Second order CARS depends on chi-5 and is much smaller, less than 2% of the Cascade process. Parallel Cascade CARS is a process where the signal photon of one CARS process leads to a virtual transition from the excited vibration level in another CARS-like process. The sequential is very similar but the signal photon leads to a virtual transition from the fundamental vibration levels and the second CARS-like process involves two phonons. Parallel Cascade CARS generates, therefore, the strongest NLO signal. It depends on the fourth power of chi-3 meaning we should have an enhanced contrast between resonant vs non-resonant signals. We tested these ideas using an Optical Parametric Amplifier (OPA) pumped by an amplified 100 fs, 1kHz repetition rate, Ti:sapphire laser system. The pump beam at 800 nm came directly from the amplified Ti:sapphire and the Stokes from the OPA at 1036 nm, 1025 nm and 1016 nm to observe a mouse ear tissue in and out of resonance with 2847 cm-1 CH2 symmetric stretching vibration. We observe the spectrum of the generated signals, always also compared with CARS signals, we measured the intensity dependence on both, pump and stokes beams, to confirm the expected Ip^33 and Is^2 dependence. We also acquire CARS and CCARS images for the same sample and showed the contrast enhancement expected.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Endoscopic fiber probe for in-vivo nonlinear imaging applications

Aleksandar Lukic1,2, Sebastian Dochow2, Olga Chernavskaia2, Ines Latka2, Christian Matthäus1,2, Anka Schwuchow2, Hyeonsoo Bae1, Michael Schmitt1, Jürgen Popp1,2

1Friedrich Schiller University of Jena, Germany; 2Leibniz Institute of Photonic Technology (IPHT), Germany; aleksandar.lukic@ipht-jena.de

Within the last years multimodal nonlinear imaging combining spectroscopic approaches like coherent anti-Stokes Raman scattering (CARS), two-photon excited auto-fluorescence (TPEF) and second harmonic generation (SHG) has shown its potential as a powerful label free imaging approach for spectral histopathology. In order to extend the applicability of this approach under in-vivo conditions suitable optical fiber concepts for an endoscopic investigation of difficult to access body regions are required. The most challenging spectroscopic modality to implement in a fiber probe is CARS. Here, we will introduce a novel CARS imaging fiber probe integrated into a compact endoscopic design enabling tissue imaging in epi direction.

The imaging fiber allows for a separation of the laser scanning end and the distal end of the fiber probe. Thus, in-vivo CARS endoscopy can be realized avoiding any moving parts or driving current. This offers the advantage of implementing small probe diameters, easier sterilization and recycling conditions.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Two-beam fs-CARS for N2 thermometry using rovibrational O- and S-branch transitions

Marita Kerstan1, Ioannis Makos1, Stefan Nolte1,2, Andreas Tünnermann1,2, Roland Ackermann1

1Institut für Angewandte Physik, Abbe Center of Photonics, Friedrich-Schiller-Universität Jena, Germany; 2Fraunhofer Institute for Applied Optics and Precision Engineering IOF, Jena, Germany; marita.kerstan@uni-jena.de

In this study we evaluate an approach for determining the N2 gas temperature in a single shot fs-CARS experiment, enabled by the observation of the rovibrational O- and S-branch transitions in an experimental setup with an ultrabroadband ~ 7 fs pulse as both the pump and Stokes pulse and an additional narrowband 1.5 ps pulse at 400 nm as a probe pulse.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

High pressure studies on carbonate crystals using coherent anti-Stokes Raman Spectroscopy

Chris-Julian Fruhner, Lkhamsuren Bayarjargal, Winkler Bjoern

Goethe University, Germany; fruhner@kristall.uni-frankfurt.de

Spontaneous Raman spectroscopy is one of the main tools for unambiguous sample characterization in diamond anvil cell (DAC) based experiments, but it has its shortcomings for investigations at simultaneous high pressure and temperature. Coherent anti-Stokes Raman spectroscopy (CARS) might overcome these problems, due to the fact that the signal intensity can be enhanced by several orders of magnitude and therefore eliminate the influence of thermal radiation or fluorescence effects [1-3].

The aim of this study is to employ coherent anti-Stokes Raman spectroscopy on carbonates in DACs at extreme conditions and to determine the pressure dependence of the Raman modes of carbonates detected by CARS.

Our results show the feasibility of CARS for high pressure measurements on carbonates. For future work we will focus on CARS at simultaneous high pressures and temperatures in order to get new insights on the phase relations of carbonate minerals under upper mantle conditions.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Evaluation of targeted cancer therapy and diagnosis of bladder cancer by Raman micro-spectroscopy

Samir F. El-Mashtoly, Hesham K. Yosef, Laven Mavarani, Dennis Petersen, Daniel Niedieker, Wissam Alsaidi, Mohammed Hammoud, Tatjana Lechtonen, Sascha K. Krauß, Axel Mosig, Carsten Kötting, Klaus Gerwert

Department of Biophysics, Ruhr-University Bochum, Germany; samir@bph.rub.de

Raman and coherent anti-Stokes Raman scattering (CARS) are label-free imaging tools for characterization of cells and tissues. Targeting epidermal growth factor receptor (EGFR) is one of the effective strategies to suppress tumors in advanced stages. Here, we have used Raman micro-spectroscopy of cell-lines as an in vitro assay for detecting the effect of K-Ras and EGFR mutations on cellular response to EGFR inhibitors. We have also monitored the distribution and metabolism of tyrosine kinase inhibitors that contain C≡C and C≡N stretching vibrations such as erlotinib and neratinib, respectively, in cancer cells. In addition, we have established spectral cytopathology method for the diagnosis of bladder cancer through the detection of urothelial cancer cells in urine sediments by Raman and CARS microscopy. The identification of urothelial cancer cells is achieved with 94% accuracy. Finally, we have performed Raman and CARS spectral histopathology of human tissues that differentiates between healthy and cancerous tissues.



WeA - O - 006: TERS and Applications

Time: Wednesday, 17/Aug/2016: 11:00am - 12:40pm  ·  Location: Safira Room
Session Chair: Volker Deckert

This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

Scopes and limitations of TERS in interrogating structure and chemistry at the nanoscale

Debdulal Roy

National Physical Laboratory, United Kingdom; debdulal.roy@npl.co.uk

Novel functional devices use complex nanomaterials systems, where morphology and chemistry can crucially affect performance. However, the lack of analytical techniques that can directly correlate morphology with functions or chemical composition at nanometre length-scales presents a major gap. We have utilised tip-enhanced Raman spectroscopy (TERS) that allows non-destructive simultaneous measurement of topographical, chemical, optical and electrical properties with nanoscale resolution (< 20 nm) by combining plasmonic optical signal enhancement with electrical mode scanning probe microscopy and novel data analysis. As a proof of concept we apply this method to operating organic solar cells and demonstrate the direct identification of nanomorphology, and its direct impact in photocurrent generation and collection. In this talk I intend to discuss the progress made so far, and limitations it imposes in investigating variety of samples using currently available tip-enhanced Raman systems.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Inhibition of insulin fibrillation – a combined Raman and TERS study

Tanja Deckert-Gaudig1, Volker Deckert1,2

1Leibniz-Institute of Photonic Technologies, Germany; 2Institute of Physical Chemistry, University of Jena, Germany; tanja.deckert-gaudig@leibniz-ipht.de

Amyloid fibril formation has since long been a topic in life science research because the deposit can have profound effects on human health. Currently, a lot of effort is put in the development of new strategies to inhibit the formation of amyloid fibrils. In our contribution the results of insulin fibrillation in presence of β-carotene and quercetin are presented. The obtained species were thoroughly characterized with tip-enhanced Raman scattering (TERS) and standard Raman spectroscopy. With this analytical approach a separate spectroscopic characterization of sample core and sample surface could be realized. We will show that amorphous aggregates rather than fibrillar structures were formed under the disturbed conditions. The spectroscopic data clearly reveal that not only the core but also the surface of the aggregates were dominated by α-helix/unordered secondary structures. Apparently, the natural products effectively suppressed the formation of well-ordered β-sheet structures, the characteristic feature of amyloid species.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Nanospectroscopy for Characterization and Control of Surface Reactions

Bin Ren

Xiamen University, China, People's Republic of; bren@xmu.edu.cn

Tip-enhanced Raman spectroscopy (TERS) is a powerful tool for nanoscale characterization. We used TERS to spatially resolve the site-specific electronic and catalytic properties of an atomically well-defined Pd/Au(111) bimetallic model catalyst at 3 nm resolution with molecular fingerprints. Benefiting from this high spatial resolution, we can directly visualize the distinct chemical (electronic) and physical (plasmonic) properties of the Pd island edges compared with the Pd terrace sites on a Au(111) surface.

If TERS study can be performed in the electrochemical environment, the electronic properties of the surface and the interaction of the molecules with the substrate can be well controlled. We designed a special spectroelectrochemical cell to eliminate the distortion of the liquid layer to the optical path. We have been able to obtain electrochemical TER spectra for surface adsorbed molecules under electrochemical potential control. We further monitor the potential dependent surface photochemical reaction on single crystal surfaces.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

SPM and TERS characterization of pristine and modified 2D materials- from graphene to TMDCs

Andrey Krayev1, Marc Chaigneau2

1AIST-NT Inc, United States of America; 2Horiba Scientific, France; akrayev@aist-nt.com

Both Raman spectroscopy and scanning probe microscopy proved to be extremely useful for analysis of numerous properties of two dimensional materials. Combination of these two techniques provides additional capabilities such tip enhanced Raman scattering ( TERS) and investigation of multiple properties of 2D materials probed by SPM as a function of the wavelength and intensity of laser illumination.

Recent advances in TERS instrumentation, dedicated TERS imaging modes and dramatic improvement in enhancement factors and reproducibility of commercially available TERS probes made TERS an everyday routine characterization tool.

We discovered that folds and the patterns mechanically imprinted in mono- to few-layer sheets of 2D carbon demonstrate similarly enhanced TERS response. In addition, the folds in graphene oxide showed, rather unexpectedly, enhanced electric conductivity.

Transition metal dichalcogenides is an actively researched class of 2D materials. TERS and tip enhanced photoluminescence can provide valuable information on their nanoscale structure and electronic properties.



WeP - O - 001: SERS and Applications

Time: Wednesday, 17/Aug/2016: 2:30pm - 4:00pm  ·  Location: Ruby Room
Session Chair: Antonio Carlos Sant'Ana

This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Visualizing Trace Molecules on ambient surfaces by Flexible and Transparent SERS-active Tape

Xiangjiang Liu, Jingjing Wang, Yibin Ying

Zhejiang University, China, People's Republic of; xjliu@zju.edu.cn

Raman imaging is a powerful tool for visualizing the composition, structure and distribution of molecules on surface of interest. However, one major limitation of it is its overlong imaging time caused by the intrinsic weak Raman signal. Here, we developed a fast Raman imaging approach based on a flexible and transparent SERS-active tape. This particular substrate can be conformably attached to arbitrary surfaces to enhance the Raman signal of targets and its good optical transparency allows collection of signal from the backside of the substrate. Therefore, by simply attaching it to sample, a fast Raman imaging can be realized. We noticed the imaging speed can be increased by serval orders of magnitude compared to theconventional approach.The proposed approach required little or no sample preparation and exhibited a good generalizability that can perform on different surfaces. We believed this methodology will provide new trend for a chemical imaging using Raman microscopy.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Abiotic Degradation of Triazine Pesticides Analyzed with Surface-enhanced Raman Scattering

Santiago Sanchez-Cortes1, Rafael JG Rubira2, Carlos JL Constantino2, Maria V Cañamares1, Jose V Garcia-Ramos1

1Instituto de Estructura de la Materia. IEM-CSIC, Madrid. Spain; 2FCT, Univ. Estadual Paulista, Presidente Prudente, SP, Brazil; s.sanchez.cortes@csic.es

Triazine herbicides are considered among the most important class of agricultural chemicals ever developped. Atrazine is by far the most employed triazine pesticides because of its high flexibility in combined treatments [1]. This herbicide continues to be widely used today in USA, but it was banned in EU from 2003 [2]. The most frequently detected atrazine degradation products are DEA (des-ethyl atrazine) and DIA (des-isoprpyl atrazine.

Therefore, the possible detection of triazine herbicies in water (lakes, rivers, etc.), related to the agricultural practices, by SERS (Surface-enhanced Raman scattering) must take into account all these effects.

In this work we present the preliminary results obtained in our laboratory on the detection of atrazine and prometryne by using different SERS substrates.

The results obtained from these experiments revealed several important facts which are discussed.

Acknowledgments

This work has been supported by the Spanish Ministerio de Economía y Competitividad (Grant: FIS2014-52212-R).


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Trace Detection of Explosives with Handheld Raman using Sputtered SERS Substrates

Carlos Gomes, Anne Dowgiallo

US BioSolutions Brasil, Brazil; cgomes@usbio.com.br

Detection of trace levels of explosives using portable devices is of crucial interest for national security. Surface enhanced Raman spectroscopy (SERS) is a unique tool that offers high sensitivity, high specificity, fast response time, and low limits of detection of various explosives such as TNT, RDX, and PETN. Newly developed SERS substrates consisting of a gold/silver alloy film on roughened glass exhibit a characteristic “nanosponge” structure that increases the Raman signal for explosives orders of magnitude compared to today’s state-of-the-art SERS substrates. This enhancement lowers the detection limit for common explosives with a pocket-size, handheld, battery-powered Raman instrument to several tens of picograms on the substrate, despite using a safe, low laser power (~20 mW @ 638 nm) and a measurement time of 10 s. Due to the spectral resolution of the Raman technique, the recorded signals allow to both identify the explosive and quantify its amount on the substrate.



WeP - O - 002: Biological Applications

Time: Wednesday, 17/Aug/2016: 2:30pm - 4:00pm  ·  Location: Esmeralda Room
Session Chair: Olivier Piot

This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

Multimodal imaging - Combining Raman and Infrared spectroscopy to investigate biological cells and tissues

David Perez-Guaita1, Kamila Kochan1,2,3, Miguela Martin1, Philip Heraud1, Dean W. Andrew4, Jack S. Richards4,5, Bayden Robert Wood1

1Centre for Biospectroscopy, School of Chemistry. Monash University, 3800, Victoria, Australia; 2Faculty of Chemistry, Jagiellonian University, Cracow, Poland; 3Jagiellonian Centre for Experimental Therapeutics (JCET), Jagiellonian University, Cracow, Poland; 4Centre for Biomedical Research, Burnet Institute, Melbourne, Victoria, Australia; 5Department of Medicine, University of Melbourne, Parkville, Victoria, Australia; bayden.wood@monash.edu

In this paper we investigate the integration of both imaging modalities containing unique FTIR and Raman signal for each pixel. Two types of cells were investigated: red blood cells infected with the Plasmodium falciparum parasite and Micrasterias, a desmid microalgal species. The microscope configuration and pixel size were selected for acquiring images and samples were fixed to a sample holder in order to measure the same cells with the same orientation. Images were first analysed individually and then registered in an extended matrix containing an FTIR and a Raman spectra for each pixel. The results indicated that the combination of both techniques provide complementary information not evident in the analysis of individual images. The assignment of haemozoin FTIR bands from malaria trophozoites was only possible after correlating the FTIR spectrum with the Raman spectrum. The correlation of the Raman and FTIR spectral variables using statistical heterospectroscopy enabled the assignment of overlapping lipid and carbohydrate bands.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Raman microspectroscopic investigation of bacteria isolated from respiratory samples on a single cell level

Sandra Kloß1,2, Björn Lorenz1,2, Stefan Dees2,3, Ines Labugger2,3, Petra Rösch1,2, Jürgen Popp1,2,4

1Friedrich Schiller University Jena, Jena, Germany; 2InfectoGnostics Forschungscampus Jena, Germany; 3Alere Technologies GmbH, Jena, Germany; 4Leibniz Institute of Photonic Technology e.V, Jena, Germay; sandra.kloss@uni-jena.de

Lower respiratory tract infections are the fourth leading cause of death worldwide. A fast idendtification of the causative pathogens can help to initiate an appropriate therapy timely. However, classical culture based methods need at least one day for identifying the pathogens. In this context, Raman spectroscopy might offer an alternative in quickly identifying different bacterial species on a single cell level. The Raman spectroscopic identification of single bacterial cells requires a prior isolation from the respective matrix like e.g. body liquids.

Here, we report about the development of a Raman spectroscopy compatible isolation protocol for bacteria out of respiratory samples. The presented isolation protocol comprises liquefaction, filtration and washing steps. We investigate the impact of this islolation strategy on the Raman spectra of single bacterial cells of typical pathogens of lower respiratory tract infections.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Shape engineered TiO2 nanoparticles in Caenorhabditis elegans: a Raman imaging based approach to assist tissue-specific toxicological studies

Luca Iannarelli1, Andrea Mario Giovannozzi1, Federica Morelli2, Francesco Viscotti2, Paolo Bigini2, Valter Maurino3, Giuseppe Spoto3, Gianmario Martra3, Erik Ortel4, Vasile-Dan Hodoroaba4, Andrea Mario Rossi1, Luisa Diomede2

1INRIM, Italy; 2Department of Molecular Biochemistry and Pharmacology, IRCCS-Istituto di Ricerche Farmacologiche “Mario Negri”, Via G. La Masa 19, 20126, Milan, Italy; 3Department of Chemistry, University of Turin, Via Giuria 7, 10125, Turin, Italy; 4Surface Analysis and Interfacial Chemistry division, Federal Institute for Materials Research & Testing (BAM), 12200, Berlin, Germany; a.giovannozzi@inrim.it

In vivo detailed spatial distribution of TiO2 NPs was here investigated for the first time using a 2D chemical imaging analysis based on Confocal Raman Spectroscopy. The invertebrate nematode C. elegans was employed as prototypical model of living organism. Rod, bipyramidal and quasi-spherical engineered TiO2 NPs with different primary particle sizes and agglomeration states were prepared, characterized and then administered to nematodes . Exploiting the typical fingerprint of TiO2 in the Raman spectrum, we monitored the biodistribution of NPs inside the worm using a non-invasive, label-free method. The high spatial resolution chemical imaging and the specificity of the Raman technique in the localization of TiO2 NPs helped in the design of behavioral C. elegans studies aimed at elucidating the relationship among the size, shape, and agglomeration state of NPs and their ability to induce specific toxic effects.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Specific anti-leukemic activity of the peptide Warnericin RK and analogues and vizualization of their effect on cancer cells by chemical Raman imaging.

Jacques Augenstreich1,2, Clemence Loiseau2, Adrienne Marchand2, Etienne Hartè1, M Garcia3, Julien Verdon2, M Mesnil4, Jean Marc Berjeaud2, Sophie Lecomte1

1CBMN, Université de Bordeaux-CNRS, France; 2EBI, Université de Poitiers-CNRS, France; 3LITEC, Université de Poitiers-CNRS, France; 4STIM, Université de Poitiers-CNRS, France; s.lecomte@cbmn.u-bordeaux.fr

Antimicrobial peptides can be used as therapeutic agents against cancer cells. Warnericin RK and derivatives (WarnG20D and WarnF14V) were tested on various, solid tumor or leukemia, cancer cells. These peptides appeared to be cytotoxic on all the cell types tested, cancerous as well healthy, but very interestingly displayed no deleterious effect on healthy mononuclear cells. The mode of action of the peptide was shown to be membranolytic, using chemical Raman imaging. The less hemolytic peptides WarnG20D and WarnF14V could be good candidates for the leukemia treatment.



WeP - O - 003: Carbon Materials

Time: Wednesday, 17/Aug/2016: 2:30pm - 4:00pm  ·  Location: Ametista Room
Session Chair: Leandro Malard

This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

Resonant Raman spectroscopy of multilayer graphenes

Ping-Heng Tan

Institute of Semiconductors, Chinese Academy of Sciences, China, People's Republic of; phtan@semi.ac.cn

Resonant Raman spectroscopy of Bernal-Stacked and twisted multilayer graphenes (MLG) have been invesigated in detail. The shear (C) mode can be well-fitted with a Breit-Wagner-Fano (BWF) shape, which is attributed to quantum interference between the C mode and a continuum of electronic transitions near the K point. The Raman intensity of the C, layer-breathing (LB) and G modes is significantly enhanced in twisted (m+n)layer graphenes (t(m+n)LGs) for specific excitation energies. This behaviour is assigned to the resonance between VHSs in the joint density of states of all optically allowed transitions in twisted MLGs and the laser excitation energy. The significant resonance effect in t(m+n)LG makes that the C and LB modes can be directly measured at room temperature by specific excitation energies, allowing direct probe of the interface coupling in t(m+n)LG and other two-dimensional heterostructures.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Second-Order Overtone and Combination Raman Modes in Bilayer Graphene: First-Principles Calculations

Pedro Venezuela1, M Calandra2, F Mauri3

1Universidade Federal Fluminense, Brazil; 2Institut de Minéralogie, de Physique des Matériaux, et de Cosmochimie, Sorbonne Universités – UPMC Paris 06,Paris, France.; 3Dipartimento di Fisica, Università di Roma La Sapienza, Roma, Italy.; pedro.venezuela@gmail.com

Double-resonant Raman (DRR) spectroscopy is a very important characterization tool for graphitic materials. In general, the 2D band is the most intense DRR peak in this kind of material. The 2D band involves the creation of two optical phonons with wave-vector close to the K-point of the Brillouin Zone. Nevertheless, there are several other DRR peaks in graphitic materials that may be useful in these materials characterization. Here, we present ab-initio calculations for intensities, positions and line shapes of small intensity DRR peaks in bilayer graphene. In our calculations we are able to reproduce the experimental measurements with excellent agreement. More importantly our calculations allow a full interpretation of the experimental results. We are able to unambiguously determine the origin of all DRR processes concerning the phonons branches, wave-vectors and relevant electronic processes.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Resonance Raman Optical Activity of Single Walled Carbon Nanotube Enantiomers

Martin Magg, Patric Oulevey, Thomas Burgi

Université de Genève, Switzerland; Martin.Magg@unige.ch

We present experimental Raman optical activity (ROA) spectra of enantio-enriched single walled carbon nanotubes (SWCNTs). Enantiomeric samples of (6,5) SWCNTs were prepared using nonlinear density gradient ultracentrifugation (DGU). Upon excitation at 2.33 eV, remarkably strong G-band signals are obtained due to strong resonance enhancement with the E22S transition of (6,5) SWCNTs. Enhancement allows measuring the vibrational optical activity (VOA) at unusually low concentrations. The obtained results are in good agreement with the single excited-state theory (SES). To our knowledge, these are the first experimental VOA spectra of SWCNTs.



WeP - O - 004: Non-Linear and Time Resolved Spectroscopy

Time: Wednesday, 17/Aug/2016: 2:30pm - 4:00pm  ·  Location: Topázio Room
Session Chair: Tullio Scopigno

This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

Probing low frequency vibrational excitations and their effect on electron, proton, and group transport in proteins

Paul Champion

Northeastern University, United States of America; champ@neu.edu

Electron, proton, and group transport reactions in proteins have been probed with vibrational coherence spectroscopy, resonance Raman spectroscopy, and ultrafast kinetic measurements. Recent studies have demonstrated how excitations and conformational interconversions associated with “soft” low-frequency vibrational modes can control reaction rates by many orders of magnitude. Examples involving specific biomolecules will be presented that show how low-frequency modes are utilized to facilitate barrier crossing and tunneling reactions.


This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

Vibrational Energy Flow in Hemeproteins

Yasuhisa Mizutani

Department of Chemistry, Graduate School of Science, Osaka University; mztn@chem.sci.osaka-u.ac.jp

Vibrational energy flow in proteins was studied by monitoring the time-resolved anti-Stokes UV resonance Raman scattering of three myoglobin mutants in which a Trp residue substitutes a different amino acid residue near heme. The anti-Stokes Raman intensities of the Trp residue in the mutants increased with similar rates after depositing excess vibrational energy at heme. This indicates that vibrational energy is not transferred through the main chain but rather through atomic contacts between heme and the Trp residue. Distinct differences were observed in the amplitude of the band intensity change between the Trp residues at different positions, and the amplitude of the band intensity change exhibits a correlation with the extent of exposure of the Trp residue to solvent water. This correlation indicates that atomic contacts between an amino acid residue and solvent water play an important role in vibrational energy flow in a protein.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Probing ultrafast photo-induced dynamics of the exchange energy in a Heisenberg antiferromagnet

Giovanni Batignani1,2, Davide Bossini3, Nicola Di Palo2, Carino Ferrante2, Emanuele Pontecorvo2, Giulio Cerullo4, Alexey Kimel3, Tullio Scopigno2,5

1Università degli studi dell'Aquila, Italy; 2Università degli studi di Roma "La Sapienza", Italy; 3Radboud University Nijmegen, The Netherlands; 4Politecnico di Milano, Italy; 5Istituto Italiano di Tecnologia, Italy; giovannibatignani@gmail.com

Manipulating the macroscopic phases of solids using ultrashort light pulses has resulted in spectacular phenomena, including metal–insulator transitions, superconductivity and subpicosecond modification of magnetic order. The development of this research area strongly depends on the understanding and optical control of fundamental interactions in condensed matter, in particular the exchange interaction. However, disentangling the timescales relevant for the contributions of exchange interaction and spin dynamics to the exchange energy (Eex) is a challenge. Here we introduce femtosecond stimulated Raman scattering to study the ultrafast photoinduced dynamics of magnetic excitations at the edge of the Brillouin zone in the antiferromagnet KNiF3. By measuring different coherent transient Raman signals, we find that femtosecond laser excitation triggers a spectral shift of the two-magnon line, whose energy is proportional to Eex. By tracking the photo-induced two-magnon line evolution, we reveal that the Eex is increased by the electromagnetic stimulus.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Weakly hydrogen-bonded water at ionic lipid interfaces observed with heterodyne-detected sum frequency generation spectroscopy

Yuki Nojima, Yudai Suzuki, Shoichi Yamaguchi

Saitama University, Japan; nojima@apc.saitama-u.ac.jp

Thedetailed structure of the imaginary part of the second-order nonlinear optical susceptibility (Imχ(2)) of the ionic lipid/water interfaces are investigated with heterodyne-detected sum frequency generation spectroscopy. A band of weakly hydrogen-bonded OH stretch appear in the region between 3500 and 3800 cm-1. In the region, broad bands are observed and their signs are opposite to those of the hydrogen-bonded OH bands observed in the region between 3000 and 3500 cm-1. The sign of the Imχ(2) indicates the relative orientation of the molecules at the interface. Thus, the bands above 3500 cm-1 are due to water oriented oppositely to that below the lipid head group. Since oppositely oriented water is not expected below the head group, the bands are attributed to water above the head group. The orientation of water above the head group is inverted depending on the electric charge of the lipid.


WeP - O - 005: Stimulated Raman and IR imaging

Time: Wednesday, 17/Aug/2016: 2:30pm - 4:00pm  ·  Location: Safira Room
Session Chair: Alexandre Rocha Paschoal

This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Stimulated Raman Scattering Microscopy for Imaging Adipocyte Development in Zebrafish

Miriam J.B. Moester1, Marjo J. den Broeder2,3, Freek Ariese1,4, Juliette Legler2,3, Johannes F. de Boer1

1LaserLaB, VU University Amsterdam, The Netherlands; 2Institute for Environmental Studies, Vrije Universiteit Amsterdam, The Netherlands; 3Institute of Environment, Health and Societies, Brunel University London, UK; 4Indian Institute of Science, Department of Inorganic and Physical Chemistry, Bangalore, India; f.ariese@vu.nl

Stimulated Raman Scattering (SRS) microscopy techniques represent a promising new route towards non-invasive label-free optical imaging with high sensitivity and molecular specificity. This research project focuses on SRS to monitor the development of adipocytes in zebrafish under influence of different diets and toxic compounds.

Lipid metabolism in zebrafish (Danio Rerio) is of particular interest as a model system for human healthy fat processing and disease. Vertebrates store lipid in adipocytes, a cell type specialized for storing fat in intracellular neutral lipid droplets. Using SRS microscopy, we investigate adipocytes in zebrafish exposed to different diets and certain toxic compounds known to have an effect on adipocyte development. The system was optimized for imaging at 2845 cm-1, which corresponds to the abundant CH2stretch vibrations in lipids. Changes not only in adipocyte prevalence but also in other quantifiable parameters such as volume can be visualized with SRS microscopy.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Femtosecond stimulated Raman microscopy (FSRM) in a flash

Jakob Nixdorf, Lars Czerwinski, Giuseppe Di Florio, Peter Gilch

Institut für Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, Germany; jakob.nixdorf@hhu.de

In 2007 our group has introduced a new non-linear technique for broadband Raman imaging, termed femtosecond stimulated Raman microscopy (FSRM). This approach allows Raman imaging with complete spectral coverage. By employing a fast (20 kHz) multi-channel detector a single stimulated Raman spectrum can be recorded in just 0.1 ms.

A noise characterization of the current instrument yields values very close to the shot-noise limit. At this noise level and an acquisition time of 0.1 ms spectra of neat organic liquids exhibit a signal-to-noise ratio of 10-20. To demonstrate the imaging capabilities of the instrument a polymer-blend consisting of two components was analyzed. Even with pixel dwell-times as short as 0.1 ms and simple univariate analysis of the data chemical maps could be produced that clearly show the microstructure of the sample.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Introducing nano-FTIR: Imaging and Spectroscopy at 10nm spatial resolution

Adrian Cernescu

neaspec GmbH, Germany; adrian.cernescu@neaspec.com

Scattering-type Scanning Near-field Optical Microscopy (s-SNOM) allows to overcome the diffraction limit of conventional light microscopy or spectroscopy enabling optical measurements at a spatial resolution of 10nm not only at visible frequencies but also in the infrared or terahertz spectral range.



ThA - O - 001: Hot Topic Session - TERS

Time: Thursday, 18/Aug/2016: 8:50am - 11:10am  ·  Location: Ruby Room
Session Chair: Ado Jorio

Spatial Coherence in Raman Scattering

Luiz Gustavo Cançado1, Ryan Beams2, Lukas Novotny3, Ado Jorio1

1Departamento de Física, Universidade Federal de Minas Gerais, 30123-970, Belo Horizonte, Brazil; 2Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA; 3Photonics Laboratory, ETH Zürich, 8093 Zürich, Switzerland; luizgustavocancado@gmail.com

The importance of spatial coherence in optics is well established, but so far it has been neglected in Raman spectroscopy. In classical textbooks, Raman scattering is usually treated as a spatially incoherent process, for which the scattered fields from spatially distinct locations are considered to be uncorrelated, and the scattered signal is then proportional to the volume of the scatterer. This approach is supported by early coherence theory stating that the field emitted by an incoherent source at a given wavelength λ is spatially uncorrelated on length-scales larger than λ/2. However, as will be discussed in this talk, this approach is not valid if we take into account the non-radiating near-field components in the light-matter interaction. We demonstrate that it is not a priori legitimate to treat Raman scattering as an incoherent process in which the signal from different sample regions is simply summed up.


Single-Molecule Tip-Enhanced Raman Scattering for Nanoscale Chemical Identification

Zhenchao Dong

University of Science and Technology of China, China, People's Republic of; zcdong@ustc.edu.cn

In this talk, I shall first demonstrate single-molecule Raman spectroscopic imaging with sub-nm spatial resolution, resolving even the inner structure of a single molecule and its configuration on the surface [1]. This is achieved by using a plasmon-enhanced nonlinear TERS technique that invokes a double-resonance process and nonlinear optical effect, thanks to the exquisite control and tuning capability provided by low-temperature ultrahigh-vacuum scanning tunneling microscopy (STM) [2]. I shall also demonstrate the power of this STM-controlled TERS technique in distinguishing adjacent but different porphyrin molecules on surfaces in real space and address the issue of how close and how similar these different molecules can be (Figure 1) [3]. The application of this technique to both the chemical identification of small molecules such as DNA bases and the defect/strain characterization of one-dimensional nanostructures such as single-wall carbon nanotubes will also be presented.


This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

High-speed Tip-Enhanced Raman Imaging

Marc Chaigneau

HORIBA Scientific, France; marc.chaigneau@horiba.com

Tip Enhanced Raman Scattering (TERS), a technique that provides molecular information on the nanometer scale, has been a subject of great scientific interest for 15 years. But regardless of the recent achievements and applications of TERS, ranging from material science and nanotechnology, strain measurement in semiconductors, to cell biological applications, the TERS technique has been hampered by extremely long acquisition times, measured in hours, required for collection of reasonably high pixel density TERS maps. In this talk, specifics of the TERS setup that enable fast, high pixel density nano-Raman imaging will be discussed: The innovative integration of technologies brings high-throughput optics and high-resolution scanning for high-speed imaging without interferences between the techniques. The latest developments in near-field optical probes also provide reliable solutions for academic and industrial researchers alike to easily get started with nanoscale Raman spectroscopy. Thanks to those latest instrumental developments, we will present the nanoscale imaging of nanopatterned flakes of graphene and graphene oxide, carbon nanotubes and exfoliated MoS2 and WS2 flakes with a spatial resolution routinely obtained in TERS maps in the 15 - 20 nm range and a best resolution achieved being of 8 nm. To continue on the way to high-speed TERS imaging, we present also here a stimulated TERS technique that offers the possibility for a substantially faster imaging of the surface. This is made by introducing a stimulating beam confocal with the pump beam into a conventional TERS setup. A billion-fold increase in the Raman signal over conventional tip-enhanced Raman spectroscopy/microscopy is shown.



ThA - O - 002: SERS Fundamentals

Time: Thursday, 18/Aug/2016: 11:40am - 12:40pm  ·  Location: Ruby Room
Session Chair: Marek Prochazka

This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Study of the interaction to 4-mercaptobenzoic acid with silver and gold nanoparticles by Surface-Enhanced Raman Scattering (SERS).

Débora G. de Oliveira1, Patrícia L. de Oliveira1, Patrícia B. Santos1, Marcelo S. L. Brasil1, Rafaella F. Fernandes1, Lúcio O. Nunes2, Antônio C. Sant'Ana1, Santiago Sánchez-Cortés3, Gustavo F. S. Andrade1

1Dept. Chem. Univ. Fed. Juiz de Fora, Brazil; 2Dept. Chem. Univ. Fed. Vale Jequitinhonha Mucuri, Diamantina, Brazil; 3Instituto de la Estructura de la Materia (IEM), Consejo Superior de Investigaciones Científica (CSIS), Serrano, Madri, Spain; gustavo.andrade@ufjf.edu.br

SERS spectra of 4-MBA on Au and Ag nanoparticles and the Raman spectra of the solid were recorded. The 900-1800 cm-1 region of the spectra is similar to the previous reports in the literature, as much as the absence of the band at 2566 cm-1, assigned to ν(SH) is an evidence of the breaking of the SH bond on both metals. In the spectral region 950-150 cm-1 we observe a new band at 527 cm-1, which has been assigned to a SS stretching mode, suggesting the formation of a molecular dimer on both surfaces. In alkaline media, the SERS spectra presented the evidence that on Ag the dimer adsorbed by the carboxylate group, but the interaction between 4-AMB dimer and Au surface seem was made through one or the two S. The absence of bands in the aromatic CH stretching region in the SERS spectra may indicate a normal configuration of 4-MBA on both Ag and Au surfaces.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Surface-enhanced Raman scattering as a higher-order Raman process

Niclas Sven Mueller1, Sebastian Heeg1,2,3, Stephanie Reich1

1Freie Universität Berlin, Department of Physics, Arnimallee 14, D-14195 Berlin, Germany; 2School of Materials, University of Manchester, Manchester M13 9PL, United Kingdom; 3present address: Photonics Laboratory, ETH Zürich, 8093 Zürich, Switzerland; niclasm@physik.fu-berlin.de

Surface-enhanced Raman scattering (SERS) is the giant increase in the Raman scattering cross section of a molecule coupled to a localized surface plasmon. We propose a microscopic theory where SERS is treated as a higher-order Raman process that contains the plasmonic excitation. SERS is described within perturbation theory as 4th- and 3rd-order scattering processes. Treating the plasmon as a quasi-particle enables us to derive analytic expressions for all coupling matrix elements. We calculate the enhancement for a molecule beside a gold nanosphere and in the hot spot of a nanodimer. We compare our theory with the theory of electromagnetic enhancement, which treats the plasmonic nanostructure as an external antenna that enhances incoming and scattered light. While there is generally good agreement on the geometry of the SERS hot spot, our theory predicts an enhancement that is several orders of magnitude stronger than the electromagnetic enhancement. This correlates with recent experiments.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Transparent glass nanopillars achieved via maskless lithography for a homogeneous SERS substrate

Anil Haraksingh Thilsted, Julia Cathrine Dyrnum, Kaiyu Wu, Michael Stenbæk Schmidt, Tomas Rindzevicius, Anja Boisen

Department of Micro- and Nanotechnology, Technical University of Denmark, Denmark; ahath@nanotech.dtu.dk

A dense array of glass nanopillars is achieved via maskless reactive ion etching in fused silica wafers. The fabrication process is simple, fast and scalable and results in large area homogeneous SERS enhancement with minimal background signal. An aluminum layer on a fused silica results in sputtered residued during etching that function as nanoscale masks. These nanoscale masks induce local differences in etch selectivity, resulting in nanopillar structures. Subsequent e-beam thin film gold deposition resulted in isolated gold caps at the tips of the nanopillars. The resulting morphology is a dense two-dimensional array of metallic nanoparticles that are used for surface enhanced Raman spectroscopy. It was found that the distance to the aluminum layer greatly affected the density of the nanopillars, and thus subsequently the SERS signal. It was found that homogeneiety could be greatly imporoved by simply introducing a cross of aluminum at the center of the wafer.



ThA - O - 003: TERS and Applications

Time: Thursday, 18/Aug/2016: 11:40am - 12:40pm  ·  Location: Esmeralda Room
Session Chair: Bin Ren

This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Core-shell structures as precursors for nanodiamonds: TERS on TNT-RDX nanocomposites

Tanja Deckert-Gaudig1, Volker Deckert2, Vincent Pichot3, Denis Spitzer3

1IPHT - Leibniz Institute of Photonic Technology, Germany; 2University of Jena, Germany; 3French-German Research Institute of Saint-Louis, France; volker.deckert@uni-jena.de

The detonation of a TNT-RDX mixture crystallized by Spray Flash Evaporation yields nanodiamonds with a size below 4 nm when detonated. This value exceeded the hitherto obtained results clearly and was associated with the unique structure the TNT-RDX nanocomposites were supposed to have. Our combined tip-enhanced Raman scattering (TNT) and standard Raman spectroscopy studies on the single particle level reveal that the TNT-RDX nanocrystals had a core-shell structure where a RDX core was surrounded by a TNT shell. The results were compared with a TNT-RDX sample that was prepared by mixing the components only after separate crystallization. From the TERS and Raman data it was concluded that this sample contained individual TNT and RDX crystals. Our analytical approach can be applied to any system where a separate spectroscopic characterization of sample core and sample surface are of interest.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Extending the plasmonic lifetime of tip-enhanced Raman spectroscopy probes

Naresh Kumar1,2, Steve Spencer1, Dario Imbraguglio3, Andrea Rossi3, Andrew Wain1, Bert Weckhuysen2, Debdulal Roy1

1National Physical Laboratory, Hampton Road, Teddington, Middlesex, TW11 0LW, UK.; 2Faculty of Science, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, Utrecht 3584 CG, The Netherlands; 3Istituto Nazionale di Ricerca Metrologica, Strada delle Cacce 91, 10135 Torino, Italy; naresh.kumar@npl.co.uk

Tip-enhanced Raman spectroscopy (TERS) is an powerful technique for simultaneous chemical and topographical mapping of a surface at the nanoscale. However, rapid degradation of TERS probes is a major bottleneck to the widespread uptake of this technique and prohibiting the success of many TERS experiments. In this work, we carry out a systematic time-series study of the plasmonic degradation of Ag-coated TERS probes under different environmental conditions and demonstrate that a low (<1 ppm) oxygen and moisture environment can significantly improve the plasmonic lifetime of TERS probes from a few hours to a few months. Furthermore, using X-ray photoelectron spectroscopy measurements on Ag nanoparticles we show that the rapid plasmonic degradation of Ag-coated TERS probes can be correlated to surface oxide formation. Finally, based on the results of this study we present practical guidelines for the effective use and storage of TERS probes to extend their plasmonic lifetime.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Reproducible Method for Fabrication of Optically Efficient TERS Probes

Thiago L. Vasconcelos1, Bráulio S. Archanjo1, Benjamin Fragneaud3, Bruno S. Oliveira1, Douglas S. Ribeiro2, Cassiano Rabelo2, Wagner N. Rodrigues2, Ado Jorio2, Carlos A. Achete1, Luiz G. Cançado2

1INMETRO, Brazil; 2UFMG, Brazil; 3UFJF, Brazil; tlvasconcelos@inmetro.gov.br

We report a route to increase the optical efficiency on conventional TERS probes [1]. The method is based on the use of a focused-ion-beam (FIB) made single groove in the vicinity of the apex of electrochemical etched gold tips. The superficial line groove limits a region at the end of the tip, leading to a localized surface plasmon (LSP). Electron energy-loss spectroscopy (EELS), combined with scanning transmission electron microscopy (STEM) are employed to map the plasmon absorption energies with high spatial and energy resolution, revealing spectral tunability of its absorption energy by changing the distance between the groove and the probe apex. Based on the experimental EELS data, complemented by discrete dipole approximation simulations, and taking into account the effective wavelength of the plasmon oscillation, we obtained a simple relation to guide the LSP resonance tuning in FIB-grooved TERS probes.



ThA - O - 004: Carbon Materials under extreme conditions

Time: Thursday, 18/Aug/2016: 11:40am - 12:40pm  ·  Location: Ametista Room
Session Chair: Paulo Tarso Cavalcante Freire

This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

In situ Raman scattering spectroscopy on nuclear materials

Patrick SIMON1, Aurélien CANIZARES1, Mohamed-Ramzi AMMAR1, Guillaume GUIMBRETIIERE1, Eric Stéphane FOTSO GUEUTUE1, Olga A. MASLOVA1, Nicole RAIMBOUX1, Florian DUVAL1, Ritesh MOHUN2, Lionel DESGRANGES2, Magali MAGNIN3, Sandrine MIRO3, Sylvain PEUGET3, Christophe JEGOU3, Nicolas CLAVIER4, Nicolas DACHEUX4, Nicolas GALY5, Nelly TOULHOAT5, Nathalie MONCOFFRE5

1CEMHTI UPR 3079 CNRS F-45071 Orleans Cedex 2; 2CEA/DEN/DEC Bat 352 Cadarache F-13108 Saint-Paul lez Durance; 3CEA/DEN/DTCD Marcoule BP 17171, F-30207 Bagnols sur Cèze; 4ICSM, UMR 5257 CEA/CNRS/UM2/ENSCM, BP 17171, F-30207 Bagnols sur Cèze; 5Université de Lyon 1, CNRS/IN2P3, UMR5828, Institut de Physique Nucléaire de Lyon (IPNL), 4 rue Enrico Fermi, F-69622 Villeurbanne Cedex; simon@cnrs-orleans.fr

Raman scattering is well-known for its efficiency to investigate defects or structural modifications in solids. The method offers peculiar abilities to couple with complex environments through optical-fiber coupled remote probeheads. A review will be given on recent results obtained by in situ Raman under irradiation (external irradiation by ion beam or self-irradiation in highly active materials) on materials for nuclear energy : actinide oxides and nuclear graphites. The former compounds exhibit a three-line structure of Raman peaks induced by irradiation that will be discussed in details. These studies on model materials help to interpret the Raman spectrum of highly-irradiated materials such as spent nuclear fuels. Besides this, the case of nuclear graphites in a complex device (T-P-irradiation-Raman) simulating the working conditions of a UNGG graphite reactor used tens of years ago will be presented, aiming to estimate the amount of remaining long-lived radioisotopes in these materials.


This contribution will be presented as a 30 minutes (25 min + 5 min for questions) invited talk.

A New Carbon Phase Constructed by Long-Range Ordered Amorphous Carbon Clusters from Compressing Fullerene Solvates

Bingbing Liu

Jilin University, China, People's Republic of; liubb@jlu.edu.cn

Carbon nanomaterials, such as nanotubes, fullerene, provide us ideal carbon sources to study novel phase and design new carbon materials induced by high pressure. A novel carbon material has been recently reported from compressing C60 solvates (C60/m-xylene) and the obtained high pressure phase---the ordered amorphous carbon cluster (OACC) structure, breaks our inherent understanding of the categorization of various phases and adds a new member to the list of structures [Wang et al, Science 337, 825 (2012)]. Here, another example of OACC is also presented from compressing C70/m-xylene in which amorphized and highly compressed C70 units act as building blocks. A new phase transition occurs in the compression process, which is very different from compressing C60/m-xylene, indicating OACC structure can be tuned by changing the initial fullerene molecules. The deformation of fullerene molecules under pressure and the formation mechanism of the high pressure hard phase have also been revealed. Our study extends the OACC structure to larger fullerenes and suggests a universal rule for the high pressure behaviors of lower symmetry systems of solvated fullerenes [Cui et al, Adv Mater 26, 725 7(2014) ]. We also have compressed a series of intercalated fullerene solvated, pre-designed by selecting various solvents with special features and found that solvents with hexagons are able to form OACC structures and promote π-electron rehybridization between high pressured induced amorphous cluster and solvents under pressure (Yao etal, Adv Mater 27, 3962 (2015).


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Resonant Raman scattering of Anthracene-Based Cokes in the Carbonization Stage

Olga Maslova1,2,3, Mohamed Ramzi Ammar4, Cristiano Fantini Leite1, Marcos A. Pimenta1

1Universidade Federal de Minas Gerais, Brazil; 2Southern Federal University, Rostov-on-Don, Russia; 3Tomsk State University, Tomsk, Russia; 4CNRS, CEMHTI UPR 3079, Université d´Orléans, Orleans, France; o_maslova@rambler.ru

To date, Raman spectroscopy became a powerful technique for characterizing carbon-based materials due to its sensitivity to defects predominately from the D band. The activation of the resonance process of this band (intervalley Raman scattering) involves peculiar electron-phonon interaction by defects with a linear behavior on Elaser, that highlights the linear wavevector dependence of the electron and hole energies near the K (or K’) points and the phonon dispersion. However, the D band behaves quite unusually upon the initial stage of the carbonization process (400-1000°C). In this work, anthracene-based coke (C14H10, a simple model molecule) was studied to clarify the resonant character of the D band using different laser excitation energies. The laser energy dependence of both the frequency and intensity seems to change with varying the pyrolysis temperatures, revealing the electronic structure modification upon the pyrolysis. Moreover, the decreasing hydrogen content seems to follow the same trend upon temperature.



ThP - O - 001: Raman Metrology

Time: Thursday, 18/Aug/2016: 2:30pm - 4:00pm  ·  Location: Esmeralda Room
Session Chair: Thiago L. Vasconcelos

This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Intensity Ratio of Resonant Raman Modes for (n,m) Enriched Semiconducting Carbon Nanotubes

Yanmei Piao1, Jeffrey R. Simpson1,2, Jason Streit1, Geyou Ao1, Ming Zheng1, Jeffrey A. Fagan1, Angela R. Hight Walker1

1National Institute of Standards and Technology (NIST), United States of America; 2Towson University, United States of America; angela.hightwalker@nist.gov

Relative intensities of resonant Raman spectral features, specifically the radial breathing mode (RBM) and G modes, of 11, chirality-enriched, single-wall carbon nanotube (SWCNT) species were established under second-order optical transition excitation. The results demonstrate an under-recognized complexity in the evaluation of Raman spectra for the assignment of (n,m) population distributions. Strong chiral angle and mod dependencies affect the intensity ratio of the RBM to G modes and can result in misleading interpretations. Furthermore, we report five additional (n,m) values for the chirality dependent G+ and G Raman peak positions and intensity ratios; thereby extending the available data to cover more of the smaller diameter regime by including the (5,4) second-order, resonance Raman spectra. Together, the Raman spectral library is demonstrated to be sufficient for decoupling G peaks from multiple species via a spectral fitting process, and enables fundamental characterization even in mixed chiral population samples.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Recognition and Quantification of Anatase, Rutile and Brookite in Binary Mixtures: a Raman Spectroscopy and Chemometric Study

Luca Iannarelli1, Luisa Mandrile1, Pasquale Esposito1, Valter Maurino2, Giuseppe Spoto2, Andrea Mario Rossi1

1INRIM, Italy; 2Dipartimento di Chimica, Università di Torino, via P. Giuria, 10125, Torino, Italy; a.rossi@inrim.it

In this work we report the elaboration of two chemometrics tools for the recognition and quantification of different TiO2 crystalline phases in binary mixtures using Raman spectroscopy. TiO2 occurs as three different polymorphs, which provide different physical chemical properties: anatase, rutile, and brookite. Discriminant Analysis method is employed in order to make a model which affords to separate and classify the mixtures (anatase/brookite, anatase/rutile, and rutile/brookite) from pure samples (anatase, rutile, brookite). The Partial Least Squares (PLS) method is used for the quantitative calibration and three predictive methods are obtained for the mixtures fractions quantification.The goodness of the models has been tested using external validation samples and the quantifications has been compared with X-ray diffraction analysis.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Raman Spectroscopy Characterization of Particulate Matter Emitted from Soot Generators and Aircraft Turbine Engines

Meghdad Saffaripour, Li-Lin Tay, Kevin Thomson, Greg Smallwood

National Research Council, Canada; meghdad.saffaripour@nrc.gc.ca

To obtain reliable soot mass concentrations from the exhaust of aircraft turbine engines using optical instruments, it is essential that the soot used for instrument calibration has the same optical properties as the soot emitted from the test engines. The optical properties of soot are dictated by its chemical structure. In this work, the spectral properties of the soot emitted from two soot generators, widely used for calibrating instruments, is compared to those of soot emitted from three aircraft turbine engines using Raman spectroscopy. The Raman spectra have been acquired with a commercial microRaman system, using 632.8-nm light for excitation at a low power to avoid excessive sample heating. Using a five bands Raman spectral analysis, spectra of soot samples have been quantified, thereby providing a wealth of information about the chemical structure of soot. The study will help us design suitable surrogate soot particulates for optical instrument calibration.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Quantifying defect in graphitic materials sorted by topology

Ado Jorio1, Joao Luiz E Campos1, Matheus Gomes da Silva1, Erlon H. Martins Ferreira2, Carlos Alberto Achete2, Rpdroigo B. Capaz3, Luiz G Cançado1

1Departamento de Física, Universidade Federal de Minas Gerais, Belo Horizonte, MG 30123-970, Brazil; 2Divisão de Metrologia de Materiais, Instituto Nacional de Metrologia, Qualidade e Tecnologia (Inmetro), Duque de Caxias, RJ 25250-020, Brazil; 3Instituto de Física, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, Rio de Janeiro, RJ 21941-972, Brazil.; adojorio@fisica.ufmg.br

Raman spectroscopy is known to be able to quantify the amount of defects in graphitic materials, by inspection of the so-called D and G Raman bands. We developed this protocol further, including the hability of differenciating when the defects are line-like or point-like in the two dimensional structure of graphene. Within the new protocol, we discuss the limitations of previously related works, and draw a correlation between well-controled lineshape analysis and principal component analysis (PCA). We applied our protocol for classifying different types of graphitic structures, from defective graphene to more amorphous structures, like charcoal.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

In-situ Raman spectroscopy for gas analysis at high pressure and high temperature

Marcus Junghanns1, Marita Kerstan1, Felix Küster2, Stefan Guhl2, Stefan Nolte1, Andreas Tünnermann1, Roland Ackermann1

1Institut für Angewandte Physik, Abbe Center of Photonics, Friedrich-Schiller-Universität Jena, Germany; 2Institut für Energieverfahrenstechnik und Chemieingenieurwesen, Technische Universität Bergakademie Freiberg, Germany; marcus.junghanns@uni-jena.de

In this study, we applied Raman spectroscopy for the gas analysis in order to determine the applicability of this technique for imaging carbon monoxide (CO) concentration during coal gasification. The experiments were carried out in a high temperature and high pressure reactor, which provides four optical ports for Raman spectroscopy during the gasification of single coal particles under controlled conditions (gas composition, gas flow, pressure and temperature). The concentration of carbon dioxide (CO2), carbon monoxide and nitrogen (N2)/argon (Ar) was analyzed in temporal and spatial resolution. The measured concentrations of the gas components under various conditions of temperature (300-900 K), absolute pressure (1-20 bar) and carrier gas (CO2, CO2/N2, CO2/Ar) were compared to the results of a gas-phase chromatograp analysis. At room temperature and a pressure between 10 and 20 bar CO concentrations down to 3% could be measured and analyzed.



ThP - O - 002: Forensic and Environmental Applications

Time: Thursday, 18/Aug/2016: 2:30pm - 4:00pm  ·  Location: Ametista Room
Session Chair: Igor K. Lednev

This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Identification and quantification of micro-plastics in marine samples from 5 µm to 5 mm by FTIR and Raman microspectroscopy

Dieter Fischer1, Andrea Kaeppler1, Julia Muche1, Klaus-Jochen Eichhorn1, Christian Laforsch2, Sonja Oberbeckmann3, Matthias Labrenz3

1Leibniz-Institut f. Polymerforschung Dresden, Germany; 2University Bayreuth, Animal Ecology I, Germany; 3Leibniz-Institut f. Ostseeforschung Warnemünde, Germany; fisch@ipfdd.de

5 – 13 million tons of plastic debris enter the oceans every year and persists in the environment because of its long-time stability. It is mostly caused by industry (microbeads in cosmetic products, cleaning agents and industrial incorrect disposed raw materials) and inappropriate disposal of waste. This waste is degraded to microplastics below 5 mm. The biological impacts of microplastics on marine ecosystems cause problems for animals, birds and humans. We show first results to identify these microplastics on samples collected from the Baltic Sea using FTIR and Raman microspectroscopy. We determine particles on filters and ascertain which of these particles actually microplastics are. Afterwards we identify the polymer and the particle size. The most identified polymers are polyethylene, polypropylene, polystyrene, PVC, polycarbonate and polyester. Evaluation of all microplastics sizes reveals that 80 % of the particles have a size below 50 µm. Further topics are discussed in the talk.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Stimulated Raman based microtomography for paleoclimate approaches on microfossils

Christian Steuwe1, Asefeh Golreihan2, Arne Deprez2, Lineke Woelders2, Rudy Swennen2, Maarten Roeffaers1

1Centre for surface chemistry and catalysis, KU Leuven, Belgium; 2Department of Geology, KU Leuven, Belgium; christian.steuwe@kuleuven.be

In this paper, we present a non-invasive and Raman-based tomographic approach to reconstruct the three-dimensional structure of micro fossils with micron and submicron resolution. These microfossils play a crucial role in paleontological studies where their preservation is studied to get accurate results from stable isotope analyses for paleoclimate reconstructions. Today, the structure and morphology of microfossils are mainly scrutinised by optical microscopes, electron microscopes and micro-computed tomography. However, getting accurate three dimensional structures of microfossils with these techniques can be challenging in terms of measurement accuracy and analysis duration. As a consequence several misinterpretations have been reported in the literature originate from artifacts of diagenetic alteration of the fossils.Our results give strong indications of the state of the surface morphology as well as 3D mineralogy and preservation state. Based on these results microfossils can quickly be screened and best samples can be selected for paleoclimatic reconstructions.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

A Raman ‘Spectroscopic Clock’ for Bloodstain Age Determination: The First Week After Deposition

Kyle C. Doty, Gregory McLaughlin, Igor K. Lednev

University at Albany, SUNY, United States of America; kdoty@albany.edu

Knowing the time since deposition (TSD) of evidentiary bloodstains is highly desired in forensics, yet it can be extremely complicated to accurately determine in practice. Here, a Raman spectroscopic approach was developed for determining the age of bloodstains up to one week old under ambient conditions. Two-dimensional correlation spectroscopy indicated a high correlation between several Raman bands and bloodstain age. Regression analysis was used to provide quantitative predictions of the TSD. It was determined that ‘new’ (1 hour) bloodstains could be easily distinguished from older bloodstains, which is very important for forensic science. Additionally, all bloodstains were identified as blood by comparing experimentally measured spectra to multidimensional body fluid spectroscopic signatures of blood, saliva, semen, sweat, and vaginal fluid. These results demonstrate that Raman spectroscopy can be used as a nondestructive analytical tool for discriminating between bloodstains on the scale of hours to days with a high degree of accuracy.



ThP - O - 003: Theory

Time: Thursday, 18/Aug/2016: 2:30pm - 4:00pm  ·  Location: Topázio Room
Session Chair: Pedro Venezuela

This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Theory of Raman Enhancement by 2D materials: the GERS effect

Eduardo Bedê Barros1, Mildred S. Dresselhaus2

1Universidade Federal do Ceará, Brazil; 2Massachusetts Institute of Technology, USA; ebarros@fisica.ufc.br

The recent observation of Raman signal enhancement for different molecules adsorbed on graphene has given rise to an important debate as to the origin of this effect, which has been generally referred to as the graphene-enhanced Raman spectroscopy effect (GERS). The enhancement factor in such systems was shown to depend on several parameters, such as the type of molecule, the orientation of the molecule adsorbed onto the grapheme surface and the Fermi energy of the grapheme system. In this work we present a third-order time-dependent perturbation theory approach proposed to describe the chemical surface enhanced Raman spectroscopy of molecules interacting either with an ideal 2D metal or with graphene.[2] A detailed analysis is performed for all the possible scattering processes involving both electrons and holes and considering the different time orderings for the electron-photon and electron-phonon interactions.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Calculation of resonance Raman intensities including Franck-Condon and Herzberg-Teller effects

JULIEN GUTHMULLER

Gdansk University of Technology, Poland; jguthmuller@mif.pg.gda.pl

Vibrational resonance Raman (RR) spectroscopy is a useful tool to provide information on structures and properties of molecular excited states. Therefore, an accurate simulation of absorption and RR spectra, by quantum chemistry methods, can help in the interpretation of experimental data as well as in the design of new compounds for specific applications e.g. in dye-sensitized solar cells or as photocatalysts.

In this contribution, simplified sum-over-state expressions are presented to calculate RR intensities, which allow inclusion of Franck-Condon (FC) and Herzberg-Teller (HT) effects. The molecular properties are calculated with density functional theory and the different methods are applied to the molecule of Rhodamine 6G. Additionally, HT effects are considered on a Ruthenium-Palladium supramolecular photocatalyst and are shown to have a significant impact on the RR intensities.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Origin of Dispersive Lineshapes in Plasmonically Enhanced Femtosecond Stimulated Raman Spectra

Aritra Mandal, Lawrence Ziegler

Boston University, United States of America; aritra@bu.edu

A theoretical model is described to explain the observed dispersive-like vibrational lineshapes reported in previous studies of plasmonically enhanced (PE) femtosecond stimulated Raman spectroscopy (FSRS). These Raman lineshapes are explained in terms of heterodyne terms between the plasmonically enhanced stimulated Raman response from the molecules located in the plasmonically enhancing regions of Au nanoparticles and the nonlinear emission/scattering due to the resonant surface plasmon resonance (SPR) of these nanoparticles. The treatment of the FSRS signal response follows the standard perturbative polarization approach apart from the familiar g4 field enhancement factor found in spontaneous SERS description, where g represents the local electromagnetic field enhancement. The SPR contribution is modeled as a plasmonically enhanced resonant two-level system. The heterodyne cross-term between these two complex third-order responses is large since both the components are plasmonically enhanced and results in the observed dispersive-like lineshape and plasmon detuning dependence.


This contribution has been accepted as a 20 minutes (15 min + 5 min for questions) oral presentation

Spectroscopic and Computational Studies of Benzo[c][1,2,5]thiadiazole Donor-Acceptor Dyes

Jonathan E. Barnsley1,2, Georgina E. Shillito1,2, Christopher B. Larsen1,2, Holly van der Salm1,2, Lei E. Wang1,2, Nigel T. Lucas1,2, Keith C. Gordon1,2

1University of Otago, New Zealand; 2Macdiarmid Institute for Advanced Materials and Nanotechnology, New Zealand; jono.barnsley@postgrad.otago.ac.nz

Donor-Acceptor (D-A) dyes incorporating benzo[c][1,2,5]thiadiazole (BTD) have shown promise in the fields of organic photovoltaics and dye-sensitized solar cells due to a low band gap and highly tuneable optical properties. Such tuneable optical properties stem from charge-transfer (CT) transitions, which are typical for D-A dyes.

This presentation reports the effect of donor-acceptor coupling and how CT behaviour can be effectively modulated. The effectiveness of density functional theory, a powerful predictive technique, to model the photo-physics of this compound series is also be reported. Specifically in this study, particular attention is paid to the influence of Hartree-Fock (HF), with six functionals specifically implemented based on their common/wide use in donor-acceptor studies.

A number of analytical techniques, including multivariate analysis, are used to compare FT-Raman and electronic absorption experimental data. Additional techniques such as resonance Raman, emission, X-ray crystallography and electro-chemistry allow for an effective and well-rounded characterisation of these dyes.



FrA - O - 001: Plenary Session

Time: Friday, 19/Aug/2016: 8:50am - 10:30am  ·  Location: Ruby Room
Session Chair: Gustavo F. S. Andrade

Raman Hyperspectroscopy for Forensic Purposes and Medical Diagnostics

Igor K. Lednev

University at Albany, State University of New York, United States of America; ilednev@albany.edu

Raman hyperspectroscopy combined with advanced statistics is uniquely suitable for characterizing microheterogeneous samples. Understanding the structure and (bio)chemical composition of samples at the microscopic level is important for many practical applications including material science, pharmaceutical industry, various (bio)analytical purposes, etc. We have recently demonstrated that Raman hyperspectroscopy opens new exciting opportunities for forensic applications by probing individual components of highly heterogeneous samples of trace evidence and providing more specific information than that expected from average spectroscopic characteristics. In particular, we target the identification and characterization of biological stains, gunshot residue and bone remains recovered at the scene of crime. Raman hyperspectroscopy has great potential for medical diagnostics due to its ability to probe multiple biochemical markers through their overall spectroscopic signatures. We have recently utilized Raman hyperspectroscopy of blood serum and advances statistics for developing a new noninvasive method for Alzheimer’s disease diagnosis.


Single Molecule Surface-Enhanced Raman Scattering: Past, Present and Future

Alexandre Brolo

University of Victoria, Canada; agbrolo@uvic.ca

It has been almost 20 years from the first single molecule SERS (SM-SERS) reports. Since then, a considerable amount of work has been done on the understanding of the physical characteristic underlying the effect. Although the phenomenon is well-established, there are still several important aspects regarding the nature of the process that are still intriguing. For analytical chemists, SM-SERS provides the ultimate limit of detection and open the door to several possibilities in terms of compound identification and quantification. Beyond the analytical application, SM-SERS also offers opportunities to obtain insights into the plasmonic characteristics of the system, including local resonances and nanostructure properties. For instance, the analysis of the spectral fluctuations (either temporal or spatial variations) observed in the SM-regime (ultra-low analyte concentrations) provides a picture of the distribution of hotspots efficiencies. The analysis of the anti-Stokes to Stokes ratio, at the SM-level, reveals information about the resonance characteristics of the nanometric environment visited by the molecule. The SM-SERS technique can also be useful for other types of investigations. It provides molecular and structural information that can be linked to fundamental mechanistic aspects of surface reactions, including kinetics and thermodynamic characteristics of adsorption processes. In this presentation, a general overview of the SM-SERS technique will be provided, together with selected examples of applications and possibilities. The goal will be to demonstrate that SM-SERS has the potential to go well beyond the obvious analytical application and become a powerful tool in surface science and nanotechnology.



FrA - O - 002: Plenary Session

Time: Friday, 19/Aug/2016: 11:00am - 11:50am  ·  Location: Ruby Room
Session Chair: Antonio Gomes Souza Filho

Characterization of Exciton Dynamics in Functional π-Electronic Systems

Dongho Kim

Yonsei University, Korea, Republic of (South Korea); dongho@yonsei.ac.kr

Here, we discuss the excitation energy migration processes of directly coupled linear porphyrin arrays (orthogonal, butadyine linked, and fused) and their exciton coupling dynamics that have been investigated both at the ensemble and single-molecule levels by ultrafast spectroscopic technique and single molecule fluorescence spectroscopy. We have revealed that the ultrafast excitation energy migration processes in molecular arrays are strongly influenced by the electronic couplings among the constituent molecules as well as the structural rigidity of overall architectures. Our investigations have been extended to H-type aggragated perylenebisimide and polythiophene oligomers. Not only intermolecular exciton couplings but intramolecular electronic structures have been investigated in a series of expanded porphyrins in conjunction with their molecular structures, the number of π-electrons (Hückel’s [4n+2] rule) as well as their conjugation pathways. Our study demonstrates a relationship between the photophysical properties such as absorption/emission properties, excited state dynamics and the aromaticity of expanded porphyrin systems.













































Poster Presentation

Session I


MoP-P-IA: Raman Optical Activity

Time: Monday, 15/Aug/2016: 5:00pm - 8:00pm  ·  Location: Exhibition Hall

Ellipsometric Raman Spectroscopy

Patricia Targon Campana1, Fernando Costa Basilio2, Eralci Moreira Therézio3, Newton Martins Barbosa Neto4, Raigna A. da Silva Zadra Armond2, Osvaldo Novaes Oliveira Jr.5, Alexandre Marletta2

1School of Arts, Sciences and Humanities, University of São Paulo, Brazil; 2Institute of Physics, Federal University of Uberlândia, Brazil; 3Department of Mathematics, Federal University of Mato Grosso, Brazil; 4Institute of Exact and Natural Sciences, Federal University of Pará, Brazil; 5Institute of Physics of São Carlos, University of São Paulo, Brazil; pcampana@usp.br

Chiral molecules are present in several systems and their discovery has been essential to the study of biological molecules in regard to the origin of life and maintenance, which has sparked interest in various areas in the last century [1]. The structural details of chiral systems are usually investigated by Optical Rotatory Dispersion (ORD) and Circular Dichroism (CD), and their conformation can also be probed with experiments of Raman Optical Activity (ROA) [2]. The present work is aimed at developing a new experimental technique to quantify ROA using ellipsometry to determine the Stokes´ parameters from Raman scattered light. The new methodology, referred to as Ellipsometric Raman Spectroscopy (ERS), is based on the decomposition of a Fourier series for determining the Stokes parameters using achromatic optical components. In order to certify the adequacy of the technique, we show the ERS results for (S)-(−)-1-phenylethanol alcohol and the SW245 chiral polymer.


Structural changes of DNA upon drug intercalation studied by Raman Optical Activity spectroscopy

Grzegorz zajac1,2, Monika Dudek1,2, Malgorzata Baranska1,2, Kamilla Malek1,2

1Faculty of Chemistry, Jagiellonian University, Poland; 2Jagiellonian Centre for Experimental Therapeutics (JCET), Jagiellonian University; malek@chemia.uj.edu.pl

Raman Optical Activity (ROA) is a very sensitive spectroscopic techniques for structure determination of many biologically active molecules. ROA spectra of nucleic acids contain information about the sugar ring conformation, the base-stacking arrangement of base rings and the mutual orientation of the sugar and base rings. The main purpose of this work was to prove possibilities of ROA in assessing changes in DNA structure occurring upon intercalation the first clinically applied platinum antitumor drug: cisplatin (cis-DDP).cis-DDP reacts mainly with adenine and guanine. Pt adducts cause significant distortion of DNA double helical structure and induce the transition of B-DNA to A-form.


Raman Optical Activity Applied to Biological Systems

Diego Mendes dos Santos, Adriano Luiz de Queiroz, Fernando Costa Basílio, Alexandre Marletta, Renata Cristina de Paula, Sydnei Magno da Silva, Raigna Augusta da Silva Zadra Armond

Universidade Federal de Uberlândia - UFU, Brazil; diegostd@hotmail.com

Raman Optical Activity (ROA)1 provides information about of chirality in molecules with high relevance for health area. In the present work, we implemented new technique to measure the ROA spectra of chiral molecules per Raman Spectroscopy by Ellipsometry (RaSE). This work aims to study of L. infantum parasitethe etiological agent of Visceral Leishmaniasis by RaSE technique. This procedure provided us a DNA concentration [S] < ng/μL. RaSE spectra were obtained as excitation light linear in polarization set up that can be decomposed in two circular polarization to obtain Stokes parameters that describes the signal ROA. Raman spectra showed vibration bands in the range of 400 to 1700 cm-1 corresponding to DNA constituents (Figure). S3 Stokes parameter indicated a chirality preponderance of LCP light over RCP light. We will study L. infantum by RaSE-ROA in order to obtain information on the structure that is lost with the use of other techniques.


Raman Optical Activity in Metal Complexes: off-resonance and in-resonance.

Patric Oulevey1, Sandra Luber2, Max Lawson1, Thomas Bürgi1

1University of Geneva, Switzerland; 2University of Zurich, Switzerland; patric.oulevey@unige.ch

Transition metal complexes (TMCs) have, besides their beautiful colors, large impact in the fields of catalysis and sensing. While they have intensively been studied with electronic spectroscopy, e.g., for their charge transfer properties, TMCs experience a renaissance in vibrational spectroscopy due to their potential to drastically enhance the inherently low signals – especially for their vibrational optical activity.

We investigated a tetranuclear cubane structure with four cobalt atoms and ligands forming a quadruple helical structure. This structure has a dark violet color, is in-resonance with 532 nm (used laser light wavelength for the ROA experiment) and thus absorbed the light strongly. Resonance ROA spectra were obtained at low incident light intensity due to the strong signal enhancement. The spectra will be presented.

Calculations to investiage the spectra have been performed and will be discussed.

Vitamin E studied with the use of Raman spectroscopy, Raman Optical Activity and DFT calculations

Grzegorz Zajac1,2, Monika Dudek1,2, Katarzyna Marzec1, Malgorzata Baranska1,2

1Jagiellonian Centre for Experimental Therapeutics, Jagiellonian University; 2Faculty of Chemistry, Jagiellonian University; katarzyna.marzec@jcet.eu

The term “vitamin E” means a group of compounds, which are both tocopherols and tocotrienols. From the biological point of view, the most important compound is alpha-tocopherol (aT). Work presents studies on aT standard on the basis of spectroscopic techniques, i.e. Raman spectroscopy (RS) and Raman optical activity (ROA) as well as theoretical vibrational analysis based on DFT calculations. As ROA is sensitive to the three dimensional structure of chiral molecules, therfore together with DFT calculation could reveal much more structural information than the conventional Raman spectroscopy. In the case of aT, we have successfully obtained ROA spectrum from neat compound, as well as from the acetone solution, after 24 hours acquisition. Raman/ROA spectra were measured with the use of ChiralRAMAN-2X (BioTools Inc.) spectrometer, equipped with 532 nm laser excitation line.



MoP-P-IB: Biological and Biomedical Applications

Time: Monday, 15/Aug/2016: 5:00pm - 8:00pm  ·  Location: Exhibition Hall

Formation of various Hb-NO2 adducts after exposure of functional RBCs to sodium nitrite

Jakub Dybas1,2, Katarzyna Marzec1, Malgorzata Baranska1,2, Stefan Chlopicki2,3

1Jagiellonian Centre for Experimental Therapeutics (JCET), Jagiellonian University; 2Faculty of Chemistry, Jagiellonian University; 3Department of Experimental Pharmacology, Jagiellonian University Medical College; katarzyna.marzec@jcet.eu

In this work the resonance Raman spectroscopy (RRS) and UV-Vis absorption spectroscopy (UV-Vis) were applied to study interaction of ferric hemoglobin (Hb) with nitrite ion in order to get a better insights into molecular properties of Hb-NO2 adducts in situ in functional RBCs. All experiments were conducted on fresh, functional red blood cells, isolated from human whole blood. The RRS spectra were recorded using two excitation lines, 488 nm and 633 nm. The UV-Vis spectra were recorded in the region 300-700 nm. Studies allowed for differentiation of various Hb species observed in RBCs after NaNO2 treatment in aerobic conditions as well as in vitro visualisation of metHb-NO2 inside RBCs. The formation of different Hb-NO2 adducts was dependent on sodium nitrite concentration, as well as whether nitrite was added as single administration or cumulative addition.



Vitamin A as a marker of liver condition: Raman imaging of tissues and isolated cells in models of liver injury

Kamila Kochan1,2, Katarzyna Maria Marzec1, Edyta Maslak1, Malgorzata Baranska1,2, Stefan Chlopicki1,3

1Jagiellonian Centre for Experimental Therapeutics (JCET), Jagiellonian University, Cracow, Poland; 2Faculty of Chemistry, Jagiellonian University, Cracow, Poland; 3Department of Experimental Pharmacology, Jagiellonian University, Cracow, Poland; kochan@chemia.uj.edu.pl

Vitamin A is a broad term, covering i.a. retinol, retinal and retinoid acid. It is known to be stored within intreacellular lipid droplest (LDs) of Hepatic Steallate Cells (HSCs). In normal conditions (healthy liver) HSCs occur in quiescent state. However, upon any type of damage they change into activated (transdifferentiated) state and loose vitamin A.

We present results of a comprehensive study on the topic of vitamin A presence under the conditions of occurrence of Non-Alcoholic Fatty Liver (NAFLD), a known liver disorder, manifested by an accumulation of excessive lipids within liver. With the use of Raman spectroscopy (532 nm excitation wavelength) we demonstrate the presence of all-trans retinol within healthy liver and its disappearance in NAFLD-affected livers. Moreover, we show the reappearance of vitamin A after successful treatment (metformin). In addition, with the use of isolated liver cells, we demonstrate vitamin A presence in LDs of HSCs and LSECs.


Label-free visualization of human epidermal cells using stimulated Raman scattering microscopy

Mariko Egawa1, Kyoya Tokunaga2, Junichi Hosoi1, Shinya Iwanaga1, Yasuyuki Ozeki2

1Shiseido Global Innovation Center; 2Department of Electrical Engineering and Information Systems, University of Tokyo; mariko.egawa@to.shiseido.co.jp

Skin is classified roughly into three layers: epidermis, dermis, and subcutaneous tissue. Epidermis is important because it acts as a barrier against dry environment and harmful external substances. The visualization of epidermal cells is important to better understand the functions and conditions of skin. Optical microscopy has been widely used for detailed investigation of epidermal cells, but its applicability is still limited because of the need for sample fixation and staining. In this study, we demonstrate in situ molecular imaging of human epidermal cells both in culture and in skin tissues using stimulated Raman scattering with subcellular spatial distribution to detect epidermal keratinocyte (KC) at differentiation stages and discriminate Langerhans cells (LCs) from surrounding KCs. We observed drastic changes of morphology in KCs at differentiation and proliferation stages both in cultured cells and skin tissues. We also identified LCs by detecting the subcellular spatial distribution of molecular components in situ.


AFM-Raman of single cells: decoupling biomolecule concentration from sampling volume for quantitative Raman measurements

Radu Boitor, Faris Sinjab, Ioan Notingher

University of Notthingham, United Kingdom; faris.sinjab@nottingham.ac.uk

We undertook experiments combining Raman imaging of neural stem cells (NSCs) with liquid atomic force microscopy (AFM) of the same cells to measure their volume. This combined information allowed us to estimate the concentration of various biomolecule constituents in the NSCs. This is important when following biological processes such as stem cell differentiation, where the morphology can drastically change, and thus the Raman intensity could change either due to a difference in biomolecule concentration or sampling volume. The combination of AFM and Raman mapping eliminates one of these unknowns.

Using a dataset of 10 cells, we compared various normalization techniques based on Raman data to the actual height maps from AFM, used PLS models to quantitatively estimate the mass of RNA and protein in the measured NSCs. We then suggest routes to estimating biomolecule concentration in the absence of AFM measurements for live cell samples.


Retinal Tissue Raman Spectra from Murine Alzheimer Model

Emerson Fonseca1,2, Lucas Lafetá2, Michelle De Caux2, Alexandre Barabosa2, João Luiz Campos2, Cassiano Rabelo2,3, Leandro Moreira2, Ado Jorio2

1Faculdade de Medicna, Univerdade Federal de Minas Gerais, Belo Horizonte, MG, Brazil; 2Departamento de Física, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; 3Programa de Pós-Graduação em Engenharia Elétrica, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; bio.labns@gmail.com

The development of an effective Alzheimer Disease diagnosis is a big global challenge. Alzheimer Disease (AD) is a dementia global epidemy, characterized by an increase in β-amyloid peptide deposition and the presence of neurofibrillary tangles in hippocampus.

Researches shows that β-amyloid deposition occurs in retinal tissue, as part of the central nervous system, years before deposition is observed in the central nervous system. Therefore, the retina emerges as great window for central nervous system, and maybe for AD early diagnosis, using optics as a detection tool.

Our goal here is to create reference data for the Raman spectra of Alzheimer transgenic mouse retina, using both dispersive Raman spectroscopy and coherent anti-Stokes Raman spectroscopy imaging for early diagnosis method for AD.


Confocal Raman imaging for probing possible intracellular targets for an anti-tumoral organometallic complex

Mónica Benicia Mamián-López, Rodrigo Bernardi Miguel, Manuel F G Huila, Koiti Araki, Ana Maria Da Costa Ferreira, Marcia L A Temperini

University of Sao Paulo, Brazil; monibe@iq.usp.br

Confocal Raman imaging assisted by multivariate analysis was applied to study possible intracellular targets in live HeLa cells treated with the organometallic complex [Cu(ISAEPY)(H2O)]. A multivariate curve resolution method was used to extract the spectroscopic profiles of the constituents and build the chemical images. The results gave an insight to possible targets where the antitumoral is causing damage and allows to complement studies focused on elucidating its mechanism of action.


Epileptic rat brain tissue analyzed by Raman spectroscopy

Aleksandra Weselucha-Birczynska1, Julia Sacharz1, Janina Zięba-Palus2, Rafał Kowalski2, Marian H. Lewandowski3, Katarzyna Palus3, Łukasz Chrobok3, Tomasz Kowalski1, Malwina Birczyńska4, Agnieszka Sozańska5

1Jagiellonian University, Poland; 2Institute of Forensic Research, Kraków, Poland; 3Department of Neurophysiology and Chronobiology, Institute of Zoology, Jagiellonian University, Kraków, Poland; 4Department of Infectious Diseases, The University Hospital in Kraków, Kraków, Poland; 5Renishaw Sp. z o.o., Warszawa, Poland; birczyns@chemia.uj.edu.pl

Neurodegenerative diseases have been of great interest to researchers.

Absence epilepsy is the neurological disease characterized by the pathological spike-and-wave discharges. WAG/Rij rats, used in this study, are the well-established model of this pathology. The aim of this study was to determine what changes in the individual parts of the rat brain tissue can be observed in epileptic rats.

We studied three brain areas: somatosensory cortex (Sc), dorsal lateral geniculate nucleus of the thalamus (DLG) and cerebellar cortex (Cc). The Raman spectra of the fresh brain tissue fragments kept in artificial cerebrospinal fluid were collected 785 nm, 442 nm, 514.5 nm and 1064 nm laser lines. The ratio of the I2930/I2850 , the I2880/I2850 and the I1300/I1356 appear to be good markers for discrimination between selected brain regions what points towards different fatty acid composition in the investigated areas.


Human lymphocytes in infectious mononucleosis studied by Raman microspectroscopy

Aleksandra Weselucha-Birczynska1, Jacek Czepiel2, Magdalena Pietruszewska1, Emilia Hola1, Paulina Moskal1, Grażyna Biesiada2, Malwina Birczyńska2, Aleksander Garlicki2

1Jagiellonian University, Poland; 2b Department of Infectious Diseases, The University Hospital in Kraków, Kraków, Poland; birczyns@chemia.uj.edu.pl

Lymphocytes establishing the line of defense to infectious microorganisms. The activation of lymphocytes occurs when they are exposed to viruses or other foreign antigens. Lymphocyte activation leads to a change in their behavior and shape.. The aim of this work was to verify how Raman spectroscopy can screen the activation of lymphocytes during this viral infection. Mononucleosis most commonly occurs in adolescents and young adults. However, the diagnosis of the disease occurs after the observation of increased concentrations of atypical lymphocytes in the peripheral blood morphologic picture. One can specify an activation of lymphocytes tracking band 521 cm1. A band at 521 cm-1 in the Raman spectra of single lymphocytes suggests that the disulphide linkages are in similar geometries in the activated cell. The average score of lymphocyte counts is consistent with the image of the band 521 cm1 that signalizing their presence.


Time-dependent Depth Profiles of Skin Hydration Following Treatment with Topical Products

Fran Adar1, Catalina David2, Vincent Larat2

1HORIBA Scientific, United States of America; 2HORIBA Scientific, France; fran.adar@horiba.com

One of the most important qualities of the condition of skin is its level of hydration. Raman depth profile measurements have been used for more than 10 years to assess hydration as a function of depth below the surface. In the current presentation we show how the hydration depth profiles evolve as a function of time after the application of products such as glycerin, and several compounded skin care products. We will also explore the possibility of measuring the migration of identifiable ingredients through the various layers of the skin as a function of time. Note that these same techniques can also be used to monitor migration of active pharmaceutical ingredients applied with various drug delivery schemes through the skin.


Highly efficient SERS-based detection of cerebrospinal fluidneopterin as a diagnostic marker of bacterial infection.

Agnieszka Kaminska1, Evelin Witkowska1, Aneta Kowalska1, Jacek Waluk1, Anna Skoczyńska2

1Institute of Physical Chemistry PAS, Poland; 2National Medicines Institute, Chełmska 30/34,; akamin@ichf.edu.pl

A highly efficient recognition unit based on surface-enhanced Raman spectroscopy (SERS) was developed as a promising, fast, and sensitive tool for detection of meningococcal meningitis, which is an extremely serious and often fatal disease of the nervous system.The results of this study confirmed that there were specific differences in SERS spectra between cerebrospinal fluid (CSF) samples infected by Neisseria meningitidis and the normal CSF, suggesting a potential role for neopterin in meningococcal meningitis detection and screening applications. To estimate the best performance of neopterin as a marker of bacterial infection, principal component analysis (PCA) was performed in a selected region (640–720 cm1) where the most prominent SERS peak at 695 cm1 arising from neopterin was observed. The calculated specificity of 95 % and sensitivity of 98 % clearly indicate the effective diagnostic efficiency for differentiation between infected and control samples.


Evaluation of Thyroid gland and neck structure in vivo by Raman spectroscopy

Lazaro P M Neto1, Maurilio Jose das Chagas2, Luis F Chagas Silva Carvalho1, Ramu Rajasekaram1, Ziwey Huang3, Airton A Martin1

1Universidade do Vale do Paraíba (UniVap), Instituto de Pesquisa e Desenvolvimento (IP&D), Laboratório de Espectroscopia Vibracional Biomédica, Av. Shishima Hifumi, 2911, Urbanova, 122444-000, São José dos Campos, SP, Brazil.; 2Hospital Policlin, Av. Nove de Julho, 430, Vila Ady´Anna, 12243-780, São José dos Campos, SP, Brazil.; 3National University of Singapore, Department of Biomedical Engineering, 21 Lower Kent Ridge Road, 119077, Singapore; amartin@univap.br

Currently, the diagnosis of certain lesions in the thyroid gland remains challenging task due to indeterminate results or suspects. Thus, patients undergo surgical procedures without the immediate need.Therefore, the in vivo spectroscopy may contribute to differentiate more precisely between malignant and benign thyroid tissues, as well as the cervical structures at the time of surgery. Also, it may guide the physicians in determining the extent of injury and surgical margins. This study aims to characterize the normal and pathological tissues of the thyroid gland in vivo and real time. In addition, it aims to study the biochemical profile of cervical structures by Raman spectroscopy in vivo.


Applications of Confocal Raman Spectroscopy in hair care

Priyanka Singh1, Leonardo R de Paula2, Airton A Martin1

1UNIVAP, Brazil; 2Natura Inovação e Tecnologia de Produtos Ltda. – Brazil; amartin@univap.br

Confocal Raman Spectroscopy, a vibrational spectroscopy technique has proven to be a valuable and sensitive experimental technique for the analyses of biological samples due to the inherent chemical specificity of vibrational frequencies in the spectrum but its ability to analyze the hair fibers remains understudied. To be efficient, it is necessary for a hair care product to permeate into the layers of the hair fiber. We demonstrate the ability of confocal Raman technique to generate information about the localization of a nano-product into the hair fibers. In this work, hair tresses were treated with hair nano-emulsion product containing nanolipids. Treated hair tresses showed significant signs of permeation of the product components in the initial layers. The data indicated that confocal Raman spectroscopy may prove to be a valuable tool in determining the permeation and hence efficiency of various hair product ingredients.


Non-invasive determination of the CO contents in tuna fish using polarization resolved resonance Raman and/or Rayleigh spectroscopy

Søren Hassing

University of Southern Denmark (SDU), Denmark; sh@kbm.sdu.dk

Carbon monoxide (CO) is used for Modified Atmosphere Packaging of fresh fish and meat. CO is added because it binds to the Myoglobin of the muscle tissue with high affinity resulting in a bright, cherry-red colored Carboxy-Myoglobin complex. The product will because of the red color appear to be more fresh and attractive for longer periods of time and thus mask the aging of the product. In the present project it is investigated whether the small wavenumber shift observed in the visible absorption spectrum of Carboxy-Myoglobin relative to the visible absorption of Oxy-Myoglobin in combination with polarization resolved resonance Raman spectra of these molecules, can form the basis of the development of a fast and non-invasive method for the screening of the presence of CO in tuna fish and meat.


SERS-based wash-free immunoassay of prostate specific antigen using microdroplet sensor

Ziyi Cheng1, Rongke Gao1,2, Andrew J. deMello3

1Hanyang University, Korea, Republic of (South Korea); 2Hefei University of Technology, China; 3ETH Zürich, Switzerland; imagicd86@gmail.com

We report a convenient immunoassay of the PSA marker without the need for washing steps. Herein, magnetic immunocomplexes are isolated by splitting droplets into two smaller parts, one used for generating magnetic immunocomplexes and the other (the supernatant droplet) containing unbound SERS nano tags. The processes of droplet generation, immunoreactions, isolation of immunocomplexes, and droplet fission are sequentially performed to achieve a wash-free immunoassay. Specifically, SERS signals were measured at 174 droplets/minute and averaged for quantitative evaluation of PSA. The limit of detection (LOD) determined by our SERS-based microdroplet sensor, was estimated to be below 0.1 ng/mL, which is significantly below the clinical cut-off value for the diagnosis of prostate cancer. In addition, because the entire assay can be carried out automatically, only a minimal sample is needed. Accordingly, the approach is expected to be useful as a potential clinical tool for the early diagnosis of prostate cancer.



Raman studies of L-Cysteine. HCl interaction with DPPC membranes

Aida Ben Altabef

Universidad Nacional de Tucumán, Argentine Republic; altabef@fbqf.unt.edu.ar

To gain a deeper insight in analysing L-cysteine ethyl ester. HCl interaction with liposomes of DPPC in anhydrous and hydrated states we performed experimental studies by Raman spectroscopy. The band at 2560 cm1 in the Raman spectrum of the solid is assigned to the S−H stretching mode. This band appears at 2582 cm1 in the Raman spectrum in solution because solvation of the Cl ion disrupts the hydrogen bonding between the H of the SH group and the chlorine atom of HCl. This band was observed in the 1.00:1.47 molar ratio in the gel and solid states. In the Raman spectrum results in the solid, when Cys interacts with the bilayer, the SH stretching band appears at 2462 and 2945cm-1, a behavior that shows the two populations present in this state. The lower frequency band is due to hydrogen bonding between the thiol H electrophilic site and any site bilayer.


Quantitative measurement and imaging of drug-uptake by bacteria with antimicrobial resistance

Andrea Mario Giovannozzi1, Andrea Mario Rossi1, Paulina Rakowska2, Ian Gilmore2

1INRIM, Italy; 2National Physical Laboratory, Hampton road, Teddington, Middlesex, UK, TW11 0LW; a.giovannozzi@inrim.it

The innate resistance of Gram-negative bacteria to antibiotics and other antimicrobials is a consequence of combinatorial effects of (a) two permeability barriers, (b) their ability to efflux antibiotics out of the cell and (c) their capacity to form antibiotic tolerant biofilms that are up to 100 times more resistant than planktonic (suspended) cells. There is an urgent need for metrology to quantitatively measure and image the localisation of antibacterial agents in bacteria and biofilms and to understand penetration and efflux processes. This will be achieved within the EMPIR project MetVBadBugs by developing innovative metrological capabilities for the label-free 3D imaging of antibacterial agents in bacteria, the traceable quantification of the vertical concentration profile of antibacterial agents in bacteria and biofilms, and for the real-time quantitative measurement of drug-uptake in bacteria and biofilms. Furthermore, novel signal enhancement strategies and advanced sample preparation methods for studying antibacterial agents will be created.


In vivo assessment of the cutaneous physiopathology by the means of a remote confocal Raman microprobe

Christophe Eklouh-Molinier1, Valérie Untereiner1, Emmanuel Froigneux2, Pascale Barlier3, Virginie Couturaud3, Michel Manfait1, Roselyne Garnotel1, Olivier Piot1,4

1URCA - UMR CNRS7369 MEDyC, France; 2Horiba Jobin Yvon SAS, Villeneuve d’Ascq, France; 3CERCO, Paris, France; 4Plateform of Cellular and Tissular Imaging (PICT), University of Reims Champagne-Ardenne, Reims, France; olivier.piot@univ-reims.fr

Skin plays an important role as an efficient barrier against external aggression. To better understand the physiopathology of the skin, a new confocal Raman probe was used in a first study to identify the spectroscopic markers associated to the skin aging. Our results showed significant differences between young and old volunteers such as a thickness of the Stratum Corneum (SC) with age, which would be in accordance with Transepidermal Water Loss (TEWL) measurements. In addition to be able to evaluate the physiopathology of the skin, a second study was realized on patients suffering from Fabry’s disease. TPrincipal Component Analysis (PCA) was used and permitted to separate the healthy volunteers from the Fabry patients. In general, these two joint studies allowed to assess the efficiency of the remote confocal Raman micro-probe for in vivo investigations, as well in dermocosmetics as in the medical field.


Divide to Conquer Methodologies for DFT Calculations of the Raman Spectra of Proteins

Valder Freire1, José Alves da Silva1, Thiago Santos1, Ewerton Wagner Santos Caetano2, Eveline Matias Bezerra1, Roner Ferreira da Costa1

1Universidade Federal do Ceará, Brazil; 2Instituto Federal do Ceará, Brazil; vnffreire@gmail.com

Four divide and conquer methodologies are proposed that allow to calculate the Raman spectra of proteins using density functional theory (DFT): (i) the independent amino acid residue approach; (ii) the secondary structure approach, in which the contribution of alpha-helices, beta-sheets and turns to the Raman spectrum are evaluated; (iii) the small monomeric subdvision method, where interactions between residues of small subdivisions of a monomer are took into account; (iv) the small dimeric and trimeric subdivision method, where interactions between residues of small subdivisions of a protein dimer and trimer contribute. Raman spectra calculations for HTD-2 defensin, the Alzheimer-related beta-amyloid peptide 42, and insulin were carried out and compared to experimental data to check for their accuracy. Raman spectral features were shown to be in good agreement with measurements, indicating a great potential to offer an accurate description of the vibrational spectra of proteins, even for low wavenumber normal modes.



MoP-P-IC: Materials

Time: Monday, 15/Aug/2016: 5:00pm - 8:00pm  ·  Location: Exhibition Hall

Pressure-induced reversible phase transition in monoglycine nitrate single crystal

Pedro de Freitas Façanha Filho1, Paulo de Tarso Cavalcante Freire2, Adenilson Oliveira dos Santos1, Ricardo Jorge Cruz Lima1, Jhonatam de Oliveira Carvalho3, Geanso Miranda de Moura4

1Universidade Federal do Maranhão, Brazil; 2Universidade Federal do Ceará, Brazil; 3Instituto Federal de Educação, Ciência e Tecnologia do Maranhão; 4Universidade Federal do Sul e Sudeste do Pará; freitasfacanha@gmail.com

Single crystal of monoglycine nitrate has been studied by Raman spectroscopy under high pressures up to 5.5 GPa. The results show changes in lattice modes in the pressure ranges of 1.1–1.6 GPa and 4.0–4.6 GPa. The first change occurs with appearance of bands related to the lattice modes as well as discontinuity in the slope of dω/dP of these modes. Moreover, bands associated with the skeleton of glycine suggest that the molecule undergoes conformational modifications. The appearance of a strong band at 55 cm−1 point to a second phase transition associated with the lattice modes, while the internal modes remain unchanged. These anomalies are probably due to rearrangement of hydrogen bonds. Additionally, decompression to ambient pressure shows that the phase transitions are reversible. Finally, the results show that the nitrate anions play an important role on the stability of the monoglycine nitrate crystal.


Study by Spectroscopy Raman of nanoparticles strontium phosphate obtained by different thermal treatments

Janaina Sobreira Rocha1, Elayne Valério Carvalho2, Pierre Basílio Almeida Fechine1,2

1Departamento de Engenharia Metalúrgica e de Materiais, Universidade Federal do Ceará; 2Departamento de Química Analítica e Fisico-Química, Universidade Federal do Ceará; janaina.s@fisica.ufc.br

In recent years, interest in the properties and effects of biomaterials based strontium has increased due to its similarity with calcium. Strontium of phosphate powders were obtained by co-precipitation and submitted to different thermal treatments. Therefore, the aim of this work was to synthesize and employ specific calcium phosphates nanoparticles into the biomaterials. Raman spectra collected from samples and in all the spectra it is possible to observe the presence of a mode with very high intensity at approximately 950 cm-1 originating from symmetric stretching vibrations of O–P–O bonds with free tetrahedral phosphate ion associating SrHAp. The internal Raman vibrations of phosphate carbonate and hydroxyl ions in apatite appear above 400 cm-1. Additionally, bands at approximately 420, 575, and 1030cm-1 correspond to characteristic stretching symmetric of PO43- groups in SrHAp. The band at about 1047 cm-1 can be assigned to CO32- stretching vibration modes.



Raman spectroscopy study of titanate nanotubes decorated with magnetite nanoparticles

Janaina Sobreira Rocha1,2,4, Pierre Basilio Almeida Fechine1,2, Josué Mendes Filho3, Odair Pastor Ferreira4

1Departamento de Engenharia Metalúrgica e de Materiais, Universidade Federal do Ceará, Bloco 729 CEP 60440-554, Fortaleza-CE, Brazil; 2Department of Analytical Chemistry and Physic-chemistry, GQMAT - Group of Chemistry of Advanced Materials, Federal University of Ceará – UFC, Campus do Pici, CP 12100, Zip Code 60451-970, Fortaleza, Brazil.; 3Departamento de Física, Universidade Federal do Ceará, P.O. Box 6030, 60455-900, Fortaleza-CE, Brazil; 4Departamento de Física, LaMFA - Laboratório de Materiais Funcionais Avançados, Departamento de Física, Universidade Federal do Ceará, P.O. Box 6030, 60455-900, Fortaleza-CE, Brazil; janaina.s@fisica.ufc.br

This work reports the preparation of a system constituted of titanate nanotubes (Na-TiNT) and magnetic iron oxide nanoparticles for environmental applications. For this we have explored the property of dyes adsorption by Na-TiNT and the ability of magnetic nanoparticles to recover nanotubes after adsorption has been finished.The preparation of Na-TiNT was performed using TiO2 hydrothermal method and decorating its surface with magnetic nanoparticles through coprecipitation method.An investigation employing Raman spectroscopy was performed for evaluation of the formed iron oxide phases. We applied two laser powers: 10.7 μW and 151 μW.Raman spectra indicated, at first, a cationic exchange reaction between (Na+) and iron ions in solution. We have detected the presence of secondary oxides when the spectrum was obtained at higher powers possibly due to the oxidation of magnetite.




Study of vibrational properties of L-Alanyl-L-Phenylalanine by Raman, FT-IR spectroscopy and ab initio calculations

Cristiano Balbino da Silva, Paulo de Tarso Cavalcante Freire, Alexander Magno Rodrigues Teixeira

Federal University of Ceará, Brazil; cristiano.balbino@fisica.ufc.br

The L-alanyl-L-phenylalanine, C12H16N2O3, is a dipeptide composed of the amino acids, alanine and phenylalanine bonded by peptide bond. Some dipeptides have presented important properties as anticancer, anti- infections, cardiovascular properties, antibacterial and antifungal agents [1], remarkable bioactivity [2], antioxidant properties [3], exhibit efficacy in treatment of cataract [4], antiretroviral [5], neural transmissions [6] and others. In this work, we present the vibrational properties of the L-Alanyl-L-Phenylalanine (Ala-Phe), this dipeptide was studied by Raman and FT-IR spectroscopy together ab initio calculations using the density functional theory (DFT). The Raman and FT-IR spectra were recorded at room conditions in the region from 20 to 3500 cm-1 and 400 to 4000 cm-1, respectively. The ab initio calculations were performed in a single molecule in your optimized form using the Gaussin03 package with the functional B3LYP and basis set 6-31 G (d, p) ++. The assignments to each 3N-6 vibrational normal modes were made with the supported of Vibrational Energy Distribution (VEDA) program [7], which provides the potential energy distribution.


Study of electronic properties in Mefenamic acid complex with Lanthanides Atoms - Raman Spectra and Ab-initio calculations.

Jorge Faria1, Fernanda Morera Royo1, Francisco Xavier de Campos2, Adriano Buzutti de Siqueira2

1Instituto de Física, UFMT, Brazil; 2Departamento de Química, UFMT, Brazil; hulk@fisica.ufmt.br

Molecular electronics, part of electronics that deals with conductive polymers and small molecules conductive, is part of the process of miniaturization of electronic devices, which are becoming smaller and more powerful over the years. Using organic molecules, combined with metal, we can create efficient devices that cater to the proposal of the consumer market. In this study, we chose mefenamic acid, widely used in the pharmaceutical industry hitherto as an organic molecule being complexed with the lanthanide series elements having spectroscopic and magnetic unique properties, investigating their structural and electronic changes for each element in the series order an application in modern electronic devices such as OLEDs. For this, we use Raman spectroscopy, noninvasive intense monochromatic light beam application technique on a sample for analyzing the result of complexation and provide the advantages of each element relative to one another, and compare it with the result expected by computer calculations.


High-temperature Raman spectra of dipeptide α-L-aspartyl-L-alanine crystal

Gardenia de Sousa Pinheiro1, Cleânio Luz Lima1, Alejandro Pedro Ayala2, Paulo de Tarso Cavalcante Freire2, Francisco Erivan de Abreu Melo2

1Departamento de Física, Campus Ministro Petrônio Portella, Universidade Federal do Piauí, CEP 64049-550, Teresina-PI, Brazil; 2Departamento de Física, Universidade Federal do Ceará, C.P. 6030, CEP 60455-760, Fortaleza-CE, Brazil.; gardenia@fisica.ufc.br

Crystals of dipeptide α-L-aspartyl-L-alanine (α-Asp-Ala), C7H12N2O5, were studied under high-temperature conditions through vibrational spectroscopy (IR and Raman), x-ray diffraction and thermal analysis (Differential Scanning Calorimetry – DSC). From the analysis of the results, it is possible to conclude that: (i) the studied material undergoes a reversible order-disorder phase transition at 373 K, where several changes were observed in the vibrational spectra, especially with vibrational modes of the units that participate directly of the hydrogen bonds; (ii) the phase transition undergone by the α-Asp-Ala crystal (about 373 K) involves changes in hydrogen bonds, possibly the rupture of at least one of them, and change in the conformation of the molecules in the unit cell.


Synthesis and physicochemical properties of novel nicollites [(CH3)2NH2][FeIIIMII(HCOO)6] (M= Zn, Ni, Cu)

Aneta Ciupa, Mirosław Mączka, Anna Gągor, Maciej Ptak, Adam Pikul

Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Poland; A.Ciupa@int.pan.wroc.pl

Metal-organic frameworks (MOFs) are known for a very wide spectrum of functionalities, properties and possible applications arising from them. Their high porosity and flexible structure have afforded excellent gas separation and sorption ability, catalytic activity and more. However, it should be remembered that MOFs exhibit also magnificent electric, magnetic, dielectric and even multiferroic attributes.

In this presentation, we report synthesis, structural and magnetic properties as well as Raman and IR studies of novel dense metal-organic frameworks DMAFeMII (MII = Zn, Ni and Cu). The studied compounds were prepared under solvothermal conditions and structure of the obtained crystals were solved by X-ray diffraction method. Except of monoclinic DMFeCu, they crystallize in P1c space group.


MOLECUR DYNAMICS IN VICINITY OF FERROELECTRIC-PARAELECTRIC PHASE TRANSITION OF [C(NH2)3]4X2SO4 (X=Cl, Br)]

Jacek Wolak

Institute of Molecular Physics, Polish Academy of Sciences, Poland; wolak@ifmpan.poznan.pl

We recently synthesized new guanidinium compounds with complex anionic sublattices formed of divalent and monovalent ions. Dielectric studies have shown that tetraguanidinium dichlorosulfate, [C(NH2)3]4Cl2SO4 (G4Cl2SO4), and tetraguanidinium dibromosulfate, [C(NH2)3]4Br2SO4 (G4Br2SO4), exhibit ferroelectric properties at room temperature [1,2]. Our Raman studies of G4Cl2SO4 allowed to find the role of molecular groups dynamics (guanidinium and sulfate ) in the slow kinetics of the phase transition, and the metastable behavior of the crystal [3].

The present work is focused on molecular dynamics in the vicinity of ferroelectric-paraelectric phase transition in G4Cl2SO4 and G4Br2SO4. The measurementswere performed using NIR Raman spectroscopy.

References

[1] Szafrański M:Ferroelectricity in the guanidinium compound [C(NH2)3]4Cl2SO4: synthesis and characterization. Phys. Rev. B. 2005;72: 054122-1-11.

[2] Szafrański M, Katrusiak A: Effect of halogen on the thermodynamic behavior and ferroelectric properties of [C(NH2)3]4Br2SO4 . Phys. Rev.B. 2006; 73: 134111-1-8 .

[3] Szafrański M, Połomska M, Wolak J: Origin of metastable properties in ferroelectric phase tetraguanidinium dichloro-sulfate. J. Phys. Chem. C. 2014;118:15556-1


in-situ Raman spectroscopy for lithium-ion batteries

Yeseul Kim1, Yeonju Park1, In Kee Han2, Sung Man Lee2, Young Mee Jung1

1Department of Chemistry, Kangwon National University, South Korea; 2Department of Nano Applied Engineering, Kangwon National University, South Korea; yeseul@kangwon.ac.kr

Secondary lithium-ion batteries are used for electrical energy storage. However thier application as power source in all-electric vehicles or grid energy storage is still hampered by the loss of electrochemical performance due to side reactions especially at the positive electrode. Raman spectroscopy is a non-destructive optical method, which allows probing the local structure of solid materials under various reaction environments. Two-dimensional (2D) correlation spectroscopy is a well-established analytical technique that provides considerable utility and benefit in various spectroscopic studies. In this study, the structural change of electrode during electrochemical reaction are monitored by Raman spectroscopy. We also performed priciple component analysis (PCA) and 2D correlation spectroscopy for better understanding the mechanism of the structural changes of electrode materials. Details of the results will be dicussed in this presentation.


Role of rare-earth ionic radii on the spin–phonon coupling in multiferroic ordered double perovskites

Raimundo Bezerra Macedo Filho1, Carlos William de Araujo Paschoal2, Alejandro Pedro Ayala2

1IFMA, Brazil; 2UFC, Brazil; macedo@ifma.edu.br

In this work, we investigated the influence of rare-earth ionic radii on spin–phonon coupling in RE2NiMnO6 double perovskites by Raman spectroscopy. Spin–phonons in dense Nd2NiMnO6 and Gd2NiMnO6 ceramics were investigated by Raman spectroscopy at low temperatures. The magnitude of the observed coupling in comparison with other isostructural compounds shows that coupling is not influenced by the rare-earth ionic radius, as well as the deviation in position of the stretching phonon in the ferromagnetic phase in relation to the anharmonic contributions follows a power law.


Infrared and Raman spectra of hydrated calcium carbonate crystals CaCO3.(H2O, 6H2O) from van der Waals corrected DFT calculations

Stefane Costa2, Valder Freire2, Ewerton Wagner Santos Caetano1, Francisco Franciné Maia Jr.3, Carlos Barboza4, Umberto Fulco4, Eudenilson Albuquerque4

1Instituto Federal do Ceará, Brazil; 2Universidade Federal do Ceará, Departamento de Física, Brazil; 3Universidade Federal Rural do Semi-Árido, Mossoró, Rio Grande do Norte, Brazil; 4Universidade Federal do Rio Grande do Norte, Departamento de Biofísica e Farmacologia, Natal, Rio Grande do Norte, Brazil; ewcaetano@gmail.com

The role of hydration on the vibrational properties of monohydrated (CaCO3.H2O, hexagonal, P31, Z=9) and hexahydrated (CaCO3.6H2O, monoclinic, C2/c, Z=4) calcite crystals, in comparison to anhydrous calcite (CaCO3, rhombohedral, R3c, Z=2), is assessed with the help of published experimental and theoretical data applying Density Functional Theory (DFT) within the Generalized Gradient Approximation (GGA) and a dispersion correction scheme. The simulated vibrational infrared and Raman spectra have a good agreement with the experimental data available, and an infrared signature of hexahydrocalcite relative to monohydrocalcite could be identified at 837 cm-1. The most important frequency signatures of the lattice, water molecules, and CO32- vibrational modes are pointed out. Phonon dispersion curves reveal that, as the hydration level of calcite increases, its LO-TO phonon splitting decreases, while the thermodynamic properties of hexahydrocalcite as a function of temperature resemble closely those of calcite, with monohydrocalcite exhibiting a very distinct behavior.


A Raman spectroscopic study on fast ionic conducting variants of Li7La3Zr2O12

Maria Elisabeth Maier1, Andreas Reyer1, Daniel Rettenwander2, Reinhard Wagner1, Maurizio Ermanno Musso1, Georg Amthauer1

1University of Salzburg, Department of Chemistry and Physics of Materials, Salzburg, Austria; 2Massachusetts Institute of Technology (MIT), Center for Materials Science and Engineering, Cambdridge, MA, USA; maurizio.musso@sbg.ac.at

Fast ionic conducting variants of Li7La3Zr2O12 (LLZO), i.e. substituted LLZOs, with cubic garnet-like structure are promising solid-state electrolytes, not least because of their good chemical stability against various electrode materials, especially Li-metal. A cubic structure is a necessary, although not a sufficient, condition for high ionic conductivity in these oxides.

This study presents (i) tetragonal LLZO, unsubstituted, and (ii) cubic variants of LLZO, supervalent substituted on the Li-site, and on the Zr-site.

The special focus of this study lies on the characterization of LLZOs via Raman spectroscopy. Bulk samples as well as single crystal samples are investigated. Polarized and non-polarized Raman measurements with different laser wavelengths at various temperatures elucidate the structures of LLZOs and determine (a) phases of LLZOs (tetragonal, cubic); (b) phase transitions in LLZOs (substituent-dependent, temperature-dependent); (c) order-disorder-phenomena; (d) substituent concentrations; (e) inhomogeneities (structural, chemical).

Determination of the temperatures of the γ, β and α relaxation processes in Nylon 6,6 by Raman Spectroscopy

Durval Bertoldo Menezes1,2, Andreas Reyer1, Maurizio Ermanno Musso1

1University of Salzburg, Department of Chemistry and Physics of Materials, Salzburg, Austria; 2Federal Institute of Triângulo Mineiro, Uberlândia, Minas Gerais, Brazil; maurizio.musso@sbg.ac.at

The relaxation range of the polymeric material Nylon 6,6 is composed basically of three relaxation processes, known as γ, β and α, in order of increasing temperature, the temperature ranges where these processes happen being labeled with characteristic relaxation temperatures Tγ, Tβ and Tα. The objective of this study is to show that Raman spectroscopy can be used as an additional tool to determine the temperature ranges where γ, β and α relaxation processes in polymeric materials get activated, this spectroscopic technique being sensitive to conformational changes and microscopic deformations within the polymeric structure, therefore delivering information directly from the source where these processes occur. We find reasonable agreement with values reported from measurements of thermal, mechanical, and dielectric properties.


Investigation on the magnetic and structural properties of CoAl2-xFexO4

Í. S. B. Ferraz1, S.W. da Silva1, T.J. Castro1,2, A. Franco Jr.3, J. M. A. Silva3, P.C. Morais1,4

1Universidade de Brasília, Brazil; 2Instituto Federal de Educação, Ciência e Tecnologia de Brasília, Brazil; 3Universidade Federal do Goiás, Brazil; 4College of Chemistry and Chemical Engineering, China; italo.sanglard@gmail.com

The aluminium substituted cobalt ferrites (CoAl2-xFexO4) brings some important changes in the structural and magnetic properties of CoFe2O4, expanding the fields of possible applications. In this work, we use Raman spectroscopy to investigate the cation distribution on the CoAl2-xFexO4 with x varying composition from 0.0 to 2.0 synthesized by combustion reaction method. The single phase spinel structure was verified by Raman spectroscopy and confirmed by X-ray diffraction (XRD). The Raman modes were blue-shifted with increase on aluminum content. In addition, it was observed that the relative intensity of vibrational bands changes as aluminium content increases. Also, the distribution of iron cations was calculated using Mössbauer spectroscopy. Based on these complementary results, it was possible to calculate the cation distribution in A- and B-sites, which was confirmed by Rietveld analysis.


Raman Spectroscopy probing of morphologic changes induced by templates in functional oxides

Bruno Sousa Araújo1, Genesis de Oliveira Lima2, Diego A. B. Barbosa2, José Renato de Oliveira Lima2, Auro Atsushi Tanaka2, Adeilton Pereira Maciel2, Marcio Aurélio Pinheiro Almeida2, Carlos William A. Paschoal1, Alejandro Pedro Ayala1

1Universidade Federal do Ceará, Brazil; 2Universidade Federal do Maranhão, Brazil; s.araujobruno@fisica.ufc.br

The template method, using templates such as ethylene glycol, cetyltrimethylammonium bromide, glycine (gly), phenol (phe) and aminoacids has been widely used to promote structural and morphologic changes in oxides used in catalysis. For these compounds, morphological modifications during the synthesis process imply in deep changes in photocatalytic properties. In this work we show that Raman spectroscopy is a powerful tool for fast detection of morphological modifications induced during the synthesis process by template method. We investigate two well-known photocatalytic oxides: Bi2WO6 (BWO) and BiOBr (BOB) synthetizes by hydrothermal method in presence of templates.


Spectroscopic and quantum chemical study of an alkaloid: Canadine

Bhawani Datt Joshi1,2, Poonam Tandon3, Sudha Jain4, Alejandro P Ayala2

1Department of Physics, Siddhanath Sc. Campus, Tribhuvan University, Nepal and Departamento de Fisica, Universidate Federal do Ceará, CE, Fortaleza, Brazil; 2Department of Physics, Lucknow University, Lucknow, 226007, U.P., India; 3Department of Chemistry, Lucknow University, Lucknow, 226007, U.P., India; 4Departamento de Fisica, Universidate Federal do Ceará, CE, Fortaleza, Brazil; bhawani@fisica.ufc.br

We have performed structural and spectroscopic analysis of a natural product, an alkaloid: canadine [1,2] with the help of Raman and FT-IR spectra. The observed vibrational wavenumbers have been computed by ab initio Hartree-Fock (HF) and density functional theory (DFT) employing B3LYP/6-311++G(d,p).

It crystallizes in a monoclinic system belonging to the P21/n space group with one molecule in the asymmetric unit [3]. The crystalline packing is governed by weak intermolecular hydrogen bonds involving both oxygens of the methoxy groups as hydrogen bond acceptors. Wavenumber assignment of the molecular vibration measured by using FT-IR and Raman based on quantum chemical calculations shows a better agreement with DFT data.

[1] Xuan, B, Wang, W, Li, DX, Acta Pharmacol. Sinica. 1994; 15: 133–135.

[2] Correché, ER, Andujar, SA, Kurdelas, RR, Gómez-Lechón, MJ, Freile, ML, Enriz, RD, Bioorganic. Med. Chem. 2008; 16: 3641–3651.

[3] Pingali S, Donahue JP, Payton-Stewart F, Acta Crystallogr., Sect. C: Struct. Chem. 2015; 71: 262-265


Raman characterization of spinel and rocksalt type lithium manganese oxides applied to rechargeable lithium batteries

Ian Rodrigues do Amaral1, Rafael Silva Alencar1, Demétrio Abreu Sena Costa2, Luciano Andrey Montoro2, Antônio Gomes Souza-Filho1

1Departamento de Física, Universidade Federal do Ceará, Ceará, Brazil; 2Departamento de Química, Universidade Federal de Minas Gerais, Minas Gerais, Brazil; ianbrasil@yahoo.com.br

Composite Lithium-rich Manganese Oxides (LMO) are the state-of-the-art cathode materials for high performance Lithium-ion batteries. Spinel or rocksalt LMO lattices contain periodic sites in their structures that make possible the insertion and extraction of lithium ions at the cathode. This configuration leads to a high charge density, low cost and reduced toxicity. However, the optimal concentration of lithium that produces the best cycling stability versus energy density is still being developed. Raman spectroscopy have the great advantage of being highly sensitive to short-range environment of oxygen coordination around both manganese and lithium ions. Here, a set of materials where obtained by controlling the composition ratio at the precursor mixture and the microwave processing temperature. Our Raman analysis of these materials revealed details of the chemical structure, lithiation degrees and phases mixing. It proved, therefore, to produce a reliable characterization of lithium battery materials, evidencing essential properties of these novel materials.


Pressure and temperature dependent Raman study in single molybdates

GILBERTO DANTAS SARAIVA

CEARÁ STATE UNIVERSITY, Brazil; gilberto.saraiva@uece.br

The molybdates crystals with the general composition as A2MO4 (A = Li, Na, K, Rb, Cs, Ag; Μ = Mo), have attracted a considerable attention due to their interesting structural, vibrational and thermodynamic properties [1,2]. This study reports the temperature and pressure dependent study of A2MO4 micro-crystals using Raman spectroscopy. The micro-crystals were prepared by the hydrothermal and chemical methods. The effect of the temperature and the hydrostatic pressure on the vibrational properties of the AMoO4 has been investigated in the temperature range from 300 to 800 K and in the pressure range from 0.5 to 8,0 GPa, respectively. The Raman data indicated that the crystal exhibits at least one temperature and pressure-induced phase transformations. Lattice dynamic calculations based on the classical rigid ion model and on the density-functional theory (DFT) were used to assign the Raman modes observed in the spectrum and to support the understanding of the mechanism driving the vibrational changes undergone by the crystals.


Raman scattering in the Magnetically Ordered Phase of Magnetoelectric LiNiPO4

Danilo Rigitano1, David Vaknin2, Gaston Barberis1, Eduardo Granado1

1Instituto de Física “Gleb Wataghin" - UNICAMP, Brazil; 2Ames Laboratory and Department of Physics and Astronomy - Iowa State University, USA; danilorigitano@gmail.com

LiNiPO4 is an antiferromagnetic insulator with localized Ni2+ spins (S=1) and large magnetoelectric coupling below TN=20.8K. Polarized Raman scattering experiments in a single crystal with ortorhombic structure show, besides the phonon spectra, extra features at low wavenumbers (<100cm-1) below TN, which are independent of applied magnetic fields along a-direction. In the X(ZZ)-X polarization, this scattering could be well modeled by the Fleury-Loudon theory of two-magnon Raman scattering, using a Heisenberg Hamiltonian with five nearest-neighbor exchange and two anisotropy parameters. These constants were refined using our Raman-scattering data and previously published inelastic neutron scattering data (INS, Jensen et al., Phys. Rev. B 79, 092413 (2009)) through a simulated annealing fitting procedure, being consistent to parameters extracted using INS data alone. In X(YZ)-X polarization, two extra peaks are observed in the magnetically ordered state, not attributable to two-magnon scattering.


Raman scattering investigation of the phase transitions in Rb2KНоF6 and Rb2KDyF6 crystals

Svetlana Krylova

Kirensky Institute of Physics SB RAS, Russian Federation; slanky@iph.krasn.ru

The crystalline, ceramic, and film materials with perovskite-like structures are widely used as functional elements due to their remarkable properties. Temperature and pressure changes in fluorides, cause a number of structural phase transitions. These crystals demonstrate phase transition under cooling: T = 403 K for Rb2KНоF6 and T = 390 K for Rb2KDyF6 (into G1 phase, space group P121/n1, Z = 2). Raman scattering spectra of Rb2KHoF6 and Rb2KDyF6 crystals have been studied in temperature range from 20 K to 399 K and from 7 K to 500 K correspondingly. Raman spectra of Rb2KHoF6 crystal are distorted due to the fluorescence process. Parameters of Raman lines have been quantitatively analyzed. The anomaly of spectra changes with temperature testify to the first order phase transitions in these crystals.


Structural, vibrational and morphological properties of La2CoMnO6 multiferroics films

Antônio Vinnie dos Santos Silva1, Rosivaldo Xavier Silva2, Carlos William Paschoal1, Alexandre Rocha Paschoal1

1Universidade Federal do Ceará, Brazil; 2Universidade Federal do Maranhão, Brazil; vinnie@fisica.ufc.br

Double perovskites with formula in A2BB'O6 form (A = La, Sr, Ca, B / B '= Co / Mn or Fe / Mo) are multiferroic materials of great interest in science because of their characteristic properties that allow applications e.g. in capacitors and memory. In addition, structural changes are perceived between the polycrystalline form and film. These properties may change according to the route used for synthesizing the material. In our work, we study La2CoMnO6 (LCMO) films synthesized by Modified Pechini Method (MPM), with three depositions and treated at different temperatures: 700, 800 and 900 °C. The films were characterized by Scanning Electron Microscopy (SEM), Energy-Dispersive X-Ray Spectroscopy (EDS), Atomic Force Microscopy (AFM), X-Ray Diffraction and Raman Spectroscopy at room and low temperatures.


Spin-phonon coupling in BaFe12O19 M-type hexaferrite

Flávio Moura e Silva Júnior1, Carlos William Paschoal2

1Universidade Federal do Maranhão, Brazil; 2Universidade Federal do Ceará; flaviomouraesjr@gmail.com

The spin-phonon coupling in magnetic materials is due to the modulation of the exchange integral by lattice vibrations. BaFe12O19 M-type hexaferrite, which is the most used magnetic material as permanent magnet, transforms into ferrimagnet at high temperatures, but no spin-phonon coupling was previously observed at this transition. In this letter, we investigated the temperature-dependent Raman spectra of polycrystalline BaFe12O19 M-type hexaferrite from room temperature up to 780 K to probe spin-phonon coupling at the ferrimagnetic transition. An anomaly was observed in the position of the phonon attributed to the Fe(4)O6,Fe(5)O6, and Fe(1)O6 octahedra, evidencing the presence of a spin-phonon coupling in BaM in the ferrimagnetic transition at 720 K. The results also confirmed the spin-phonon coupling is different for each phonon even when they couple with the same spin configuration.


High-temperature ferromagnetic clusters into Ba-doped La2NiMnO6

Diego Augusto Batista Barbosa1, Carlos William Araujo Paschoal2

1Departamento de Física, Universidade Federal do Maranhão, Campus do Bacanga, 65085-580, São Luis - MA, Brazil.; 2Departamento de Física, Universidade Federal do Ceará, Campus do Pici, 65455-900, Fortaleza-CE, Brazil; dab.barbosa@gmail.com

Ferromagnetic semiconductors are key materials because of their applications in spintronic devices. Magnetodielectric semiconductor oxides are important because they can be used applying electric fields to control the magnetic properties. La2NiMnO6 emerged as an important magnetodielectric oxide because its high Curie temperature near room temperature. In this paper we report spin-phonon coupling above the Curie temperature in highly disordered La2NiMnO6 doped with barium samples, which evidences that disordered rare-earth nickel manganites ceramics with double perovskite exhibit ferromagnetic clusters above the ferromagnetic transition.


Spin-phonon and magnetostriction phenomena in CaMn7O12 helimagnet probed by Raman spectroscopy

Ariel Nonato Silva1, Carlos William Paschoal2, Adeilton Pereira Maciel1, Susana Yañez Vilar3, Maria Antonia Rodriguez3, Manuel Sánchez Andújar3

1UFMA, Brazil; 2UFC, Brazil; 3UDC, Spain; ariel.nonato@gmail.com.br

Magnetically-induced polarization materials have been intensively investigated because of their novel physics and their potential applications in multi-functional devices. In these materials the electric polarization is strongly sensible to applied magnetic fields, being very suitable for electric control of magnetic properties and, consequently, applicable to spintronics and storage devices. Among magnetically-induced polarization materials CaMn7O12 (CMO) has emerged as a singular multiferroic material exhibiting the largest induced electric polarization has been measured so far. We carefully investigated the temperature-dependent phonons in CMO from room temperature down to 10K. The temperature dependence of the Raman mode parameters shows remarkable anomalies at both antiferromagnetic and incommensurate transitions that this compound undergoes at low temperatures. The anomalies observed at the magnetic ordering transition indicate a spin-phonon coupling at the higher-temperature magnetic transition in this material and a magnetostriction effect at the lower-temperature magnetic transition.


Vibrational spectroscopic studies of cis and trans cyclic diamides

Ahsan Ali Khan1, Andrew Paul Mendham1, Babur Zahurridin Chowdhry1, Trevor John Dines2

1University of Greenwich, United Kingdom; 2University of Dundee, United Kingdom; ka38@greenwich.ac.uk

The Vibrational spectroscopic studies was carried out on six-membered (Cyclo(Gly-Gly), CGG) and 10-membered (1,6-diaza-2,7-cyclodecadione, DACD) cyclic diames in the solid state using Raman and FT-IR spectroscopic techniques. The bands due to amide I mode (C=O stretching vibrations) can be observed at 1655 cm-1 (Raman) and 1696 cm-1 (FT-IR) in CGG, 1640 cm-1 (Raman) and 1639 cm-1 (FT-IR) in DACD. This mode shows a downward shift on N-deuteration, of the order of about 30 cm1 in CGG, compared to trans amides in DACD(~12cm-1). A band due to the cis-amide II mode is found at 1520 cm1 (Raman, CGG) and the trans amide II at 1563 cm1 (FT-IR, DACD). This mode has a smaller shift on N-deuteration (~11 cm-1, CGG) compared to the trans-amide II mode (~60 cm-1, DACD). Hence, the location of the amide I and II modes can be very useful in determining cis or trans amides in cyclic diamides.


Crystal lattice vibrations and their coupling with magnetic correlations in CuSb2O6

Damaris Tartarotti Maimone1, Eduardo Granado1, John Neumeier2, Aaron Christian2

1Institute of Physics “Gleb Wataghin”, University of Campinas – UNICAMP; 2Department of Physics, Montana State University; damaris.tm2@gmail.com

CuSb2O6 is a transition metal oxide which display antiferromagnetism (AFM) with reduced dimensionality. Magnetic susceptibility measurements in CuSb2O6 can be well described considering a one-dimensional spin S=1/2 Heisenberg AFM model below 100K. We investigated the lattice, electronic and magnetic ground state and fluctuations of a CuSb2O6 single crystal by means of Raman scattering. A comparison between the polarization-resolved phonon lines and ab-initio lattice dynamical calculations allowed us to identify the observed vibrational modes. To access the magnetic correlations, several Raman spectra were taken at temperatures between 20K-450K. We observed an anomalous softening of some phonon modes on cooling, caused by spin-phonon coupling effect. Furthermore, we observed a width anomaly for a stretching mode of oxygen octahedra at T≈210K, and we suggest it is related to orbital ordering of the Cu atoms. This possible orbital ordering might be one of the keys to understand the intriguing magnetic behavior in this compound.


Study of non stoichiometric thin films of titanium nitride deposited using Plasma technique by Raman spectroscopy

Leonardo Ferreira Soares1, Bartolomeu C. Viana1, Rômulo M. de Sousa1, Marco A. Sacillori2, FRANCISCO ERONI PAZ SANTOS1

1ufpi, Brazil; 2ufpe, Brasil; franciscoeroni@gmail.com

In this work we have analyzed the influence of the deposition time and the type of substrate on the stoichiometry of the thin films of titanium nitride (TiN) by Raman spectroscopy. These thin films were grown on silicon substrates and silicon subtrates with gallium spheres deposited uniformly (by MOCVD), using plasma cathodic cage technique with different times of deposition. Using the Raman spectra it is possible to obtain the stoichiometry of the TiN films and the relationship of N/Ti, applying the residual method with both Gaussian and Lorentzian distribution.



Raman and Infrared Activity of Low-Frequency Interlayer Modes in 2D GaSe

Raphael Longuinhos, Jenaina Ribeiro Soares

Universidade Federal de Lavras, Brazil; jenainassoares2@gmail.com

The beyond-graphene two-dimensional (2D) materials are envisioned as the future technology for optoelectronics, and the study of the group IIIA metal monochalcogenides (GIIIAMM) in 2D form is an emerging research field. Bulk gallium selenide (GaSe) is a layered material from this family widely used in nonlinear optics and is promising as lubricant. The knowledge about the expected Raman and infrared spectroscopic signature of low-frequency interlayer breathing and shear modes of few-layer GaSe is highly desirable to its fundamental characterization.

Here we use symmetry arguments to investigate the Raman and infrared activity of the low-frequency interlayer modes expected in few-layer GaSe. Strategies to distinguish the number of layers and the β and ε polytypes are discussed, as well as comparisons with the bulk spectroscopic signature. Our analysis opens new perspectives about the study of interlayer interactions in GIIIAMM 2D materials and its role in the mechanical properties in these new materials.


A Vibrational Spectroscopic Study of the Degradation Products of Cycloserine

Andrew Paul Mendham1, Ahsan Ali Khan1, Trevor Dines2, Babur Chowdhry1

1University of Greenwich, United Kingdom; 2University of Dundee, United Kingdom; ma22@gre.ac.uk

Cycloserine (Cys) is an antibiotic which is used for the treatment of mycobacterium tuberculosis infections. Cys is known to degrade under acidic and neutral conditions to form a number of different compounds. Two such degradation products are 3,6-bis(aminoxymethyl)-2,5-piperazinedione (AMDKP) and 3,6-dimethylene-2,5-piperazinedione (DMDKP).

Solid state Raman spectra of N-protonated and N-deuterated isotopomers for AMDKP and DMDKP have been recorded.

The cis amide II mode of AMDKP can be observed at 1502 cm-1 which would suggest that the six membered ring adopts a boat conformation.

The cis amide II mode of DMDKP appears as a relatively weak signal at 1499 cm-1 and experiences a deuterium shift of ~ 50 cm-1. It is evident that there is greater N-H character in the cis amide II mode of DMDKP compared to other diketopiperazines (DKPs), possibly attributed to resonance effects associated with the dimethylene functional group.


The solvent polarity dependence of the polymorphism in stearic acid

Luiz Fernando Silva1, Francisco Ferreira Sousa2, Waldomiro Paschoal Jr1, Gardênia Pinheiro3, Paulo de Tarso Freire4, Josué Mendes Filho4, Sanclayton Geraldo Moreira1

1Univesidade Federal do Pará, Brazil; 2Universidade Federal do Sul e Sudeste do Pará; 3Universidade Federal do Piauí; 4Universidade Federal do Ceará; fernando.lbt@gmail.com

In this work, the polymorphism of stearic acid (C18H36O2) as a function of organic solvent polarity was studied. Polycrystalline samples of stearic acid were grown by slow evaporation technique using five different solvents (hexane, heptane, toluene, dichloromethane and methanol). The polymorphic forms were identified by X-ray diffraction experiments and two polymorphs: C (monoclinic) and Bm (monoclinic) were observed. The lattice parameters of the crystalline phases were refinements using Rietveld method, and its quantitative composition was estimated as function of the solvent polarity. Fourier transform infrared spectroscopy and differential scanning calorimetry were used as complementary techniques and corroborated with the X-ray diffraction results. Infrared spectroscopie technique was performed to study of vibrational properties of stearic acid in the crystalline phase and differential scanning calorimetry measurements provided information about the thermodynamic behavior of polymorphism phenomenon, showing that C form of the stearic acid is the most stable form at high temperature.


Phase transitions in ionic liquids: A study by Raman spectroscopy, x-ray diffraction and differential scanning calorimetry.

Thamires Andrade Lima1, Vitor Hugo Paschoal1, Luiz Felipe de Oliveira Faria1, Mauro Carlos Costa Ribeiro1, Fábio Furlan Ferreira2, Fanny Nascimento Costa2, Carlos Giles3

1Universidade de São Paulo, Brazil; 2Universidade Federal do ABC, Brazil; 3Universidade de Campinas, Brazil; thamires@iq.usp.br

Phase transitions in two ionic liquids, butyl-trimethylammonium bis(trifluoromethanesulfonyl)imide, [N1114][NTf2], and methyl-tributylammonium bis(trifluoromethanesulfonyl)imide, [N1444][NTf2], were investigated by differential scanning calorimetry (DSC), X-ray diffraction (XRD) measurements and Raman spectroscopy. XRD and Raman spectra were obtained as a function of temperature at atmospheric pressure (100 – 300K), and also under high pressure at room temperature (0.1 MPa – 2.5 GPa) using a diamond anvil cell (DAC).Both the ionic liquids studied exhibit only glass transition (Pg ~ 1-1.5 GPa) at the pressure range investigated at room temperature. On the other hand, they presented four different phases at the temperature range studied, under atmospheric pressure. It was also possible to conclude there is a correlation between the BP and QES in glassy state.


Structural order, magnetic and intrinsic dielectric properties of magnetoelectric La2CoMnO6

Rosivaldo Silva1, Alan Menezes1, Rafael Almeida2, Roberto Moreira3, Xavi Marti4, Helena Reichlova4, Miroslav Maryško4, Marcos Rezende5, Carlos William Paschoal6

1Universidade Federal do Maranhão; 2Instituto Federal de Educação, Ciência e Tecnologia do Maranhão; 3Universidade Federal de Minas Gerais; 4Institute of Physics ASCR, v.v.i.; 5Universidade Federal de Sergipe; 6Universidade Federal do Ceará; rosivaldo.xs@gmail.com

La2CoMnO6 (LCMO) have been intensively investigated due to their peculiar magnetic electric , magnetoelectric , magnetoresistance and multiferroic properties. This plethora of different and coupled electric and magnetic properties has enabled the application of these compounds into new devices and spintronics. Changes in structural order induce critical changes in magnetic and electric properties, as well as in the electronic and ionic conductivities. By tuning the synthesis conditions it is possible to control the B-site structural order in manganites with double perovskite structure, which is the preponderant parameter to define the actual potential for of these compounds in devices and applications. Therefore, we report a way to control the B-site disorder in LCMO ceramics obtained by polymeric precursors method. Our results prove that the site ordering can be improved by changing the calcination temperature and, simultaneously echoing in changes of the intrinsic dielectric and magnetic properties of LCMO.


Assessing the anion effect on the high-pressure response of ionic liquids using Raman spectroscopy

Vitor Hugo Paschoal, Arno A Veldhorst, Mauro Carlos Costa Ribeiro

University of São Paulo, Brazil; paschoal.vhp@gmail.com

In this work, we consider the effect of the anion type in the pressure response of ionic liquids based on the 1-butyl-3-methylimidazolium cation with nitrate ([NO3]-) and bis(trifluorosulfonylmethane)imide ([NTf2]-) anions. The results of this work allowed us to probe the influence of a smaller anion with less charge delocalization, such as [NO3]- in comparison with [NTf2]-,on the properties of liquid and glassy phases of these ionic liquids by evaluating the frequency shifts of intermolecular cation modes, the quasi-elastic scattering intensity Boson peak frequency shifts as function of pressure.


Micro-Raman spectroscopy of hybrid inorganic-organic polymers for wood and paper protection

Pier Paolo Lottici1, Laura Bergamonti2, Claudia Graiff2, Clelia Isca2, Giovanni Predieri2

1Physics and Earth Sciences Department, University of Parma, Italy; 2Chemistry Department, University of Parma, Italy; lottici@fis.unipr.it

New polymers for the protection of artworks of interest for cultural heritage, in particular of lignocellulose materials, are characterized by μ-Raman spectroscopy. The polymers are polyamidoamines (PAA) functionalized with alcoholic or siloxanic groups (PAAOH or SiPAA) obtained from N,N-methylenebisacrylamide (MBA) by addition reaction with ethanolamine (EtA) or aminopropyltriethoxysilane (APTES), respectively. SiPAA (an hybrid inorganic-organic polymer) has been tested for wood, whereas PAAOH also for paper preservation. The kinetics of the addition reaction (Michael-type reaction) has been followed by Raman spectroscopy: the reaction kinetics has been tracked by monitoring the decrease of the intensity of the C=C stretching mode of bisacrylamide. The polymer acts as an effective deacidification material without altering the chromatic and mechanical characteristics of paper.


Raman spectroscopy gives insights into polymer microspheres

Michal Pelach1, Zuzana Kronekova2, Petra Mazancova2, Lucia Uhelska2, Dušana Treľová2, Igor Lacík2, Peter Siffalovič3, Eva Majková3, Tibor Hianik1

1Faculty of mathematics physics and informatics, Comenius university, Slovak Republic; 2Polymer Institute, Slovak Academy of Sciences, Bratislava, Slovakia; 3Physics Institute, Slovak Academy of Sciences, Bratislava, Slovakia; m.pelach@gmail.com

Raman spectroscopy was used to measure 3D polymer distribution in microspheres used in medical studies.

Microspheres are made of alginate crosslinked with divalent cations as Ca or Ba. Alginate microspheres can be used as a carrier for drug or cell encapsulation [1]. By using vibrational band of alginate and internal standardization, we have composed calibration curve to quantify the local concentration of alginate in microspheres.

Until now only confocal laser scanning microscopy (CLSM) was used for assessing the relative concentration of alginate. Our measurements show a good overlap with CSLM and, moreover, give absolute concentration.

Acknowledgments

This work was supported by the Slovak Research and Developmental Agency under the contract No. APVV-14-0858, APVV-14-0120, APVV-14-0267 and by the Juvenile Diabetes Research Foundation. JDRF Grant No. 2-SRA-2014-288-Q-R

References

[1] Orive G, Santos E, Poncelet D, Hernández RM, Pedraz JL, Wahlberg LU, et al. Trends in Pharmacological Sciences 2015; 36(8):537–46.


Study of the optical electronics properties in oxides graphene multilayers by power Raman laser induced

Gabriela Poma1, Adela Perez2, Maria Lopez1, Maria Quintana1, Ana Champi3

1PUCP , Lima-Peru; 2UNI, Lima-Peru; 3UFABC, Brazil; ana.champi@gmail.com

In this work, we study the influence of the laser to thereby conveniently manipulate the optoelectronic properties of GO, from the Raman spectra was possible to quantify the crystal size and energy gap depending on the power. Proving that the heat treatment applied to MGO controls the degree of oxidation, which is related to the energy gap, which creates opportunities for various applications. It is also noted that for a heat treatment of 80 ° C, a smaller crystal size is obtained with respect to MGO, because depending on the power which is working you can find a smaller crystal size, equally to the energy gap, depending on the application needed. It was found that for some power MRGO worked to obtain a value smaller crystal size relative MGO; being the less stable as the change in the peak position and width G regarding MGO is greater.






































Poster Presentation

Session II

WeP-P-IIA: SERS and Applications

Time: Wednesday, 17/Aug/2016: 5:00pm - 7:00pm  ·  Location: Exhibition Hall



Bovine Serum Albumin binding to mercapto-capped gold nanoparticles: study of different capping agents on bioconjugation reaction

Raísa Lacerda, Vanessa Linhares, Jonnatan Julival Santos, Paola Corio

University of São Paulo, Brazil; paola@iq.usp.br

SERS is a powerful technique for the detection and quantification of proteins.One of the fundamental requirement in the development of bio-conjugated materials is the understanding of how the various elements present in the conjugate interact with each other.In this work, in order to gain insight into nanoparticle-capping agent-protein interaction, the coating of gold nanoparticles (AuNPs) with 3-Mercaptopropionic acid, 4-Mercaptobenzoic acid and 11-Mercaptoundecanoic acid was studied. We investigated different ratios between mols of gold and mols of the capping agent in order to establish the best condition, i.e. the smallest concentration of the capping agent to completely modify the AuNP. The covalentconjugation of AuNPs to Bovine Serum Albumin, via the crosslinker reaction EDC/NHS, was investigated on different reaction conditions. The results show that the ratio of 5% mols of gold/mols of the capping agent is the optimized relative concentration to further chemical modifications of the AuNP.


Study of interaction complex DNA/Au-NPs due to the effect of plasmon located through Raman Spectroscopy

Ricardo Eulises Báez Cruz1,2,3, Maria Fernanda Vargas Charry2, Manuel Melendrez Castro3, Carlos Vargas Hernandez2

1Department of Physics ,University of Concepcion, Chile; 2Optical Properties Laboratory Materials (POM), National University of Colombia campus Manizales; 3Advanced Nanocomposites Research Group (GINA), Hybrid Materials Laboratoy (HML), Department of Materials Engineering (DIMAT), University of Concepcion, 270 Edmundo Larenas, Box 160-C, Concepcion 4070409, Chile; rebaezc@unal.edu.co

We reported enhanced signal of DNA owing interaction with gold nanoparticles (AuNPs), which synthesized by the microwave assisted route. These Au-NPs were combined with DNA extracted from pig spleen. The system was analyzed through Raman spectroscopy for check if there is any SERS effect. The PO-2 pick was associated to frequency at 1093 cm-1 with 8% of vibration enhanced and the vibration of ring Adenine was associated to band at 1199 cm-1 with 21% enhanced. Timine had its maximum vibration enhanced with 100 % at 1383 cm-1 due to the bending bond CH3. At 1423 cm-1 bond C2H belonging to Deoxirybose due to streching vibration with 23% intensity enhanced. All these possible arise could be due to Au-NPs plasmon effect interacting with DNA. SERS effect with DNA was evidenced, these routes characterization to open the possibilities of detecting DNA, potentiate diagnostic methods with future biomedical applications.


Detection of CB Materials Using SERS

Sila Jin1, Joohee Oh1, Yeonju Park1, Jae Hwan Lee2, Young Mee Jung1

1Kangwon National University, Korea, Republic of (South Korea); 2Agency for Defense Dvelopment, Korea, Republic of (South Korea); jsira@kangwon.ac.kr

To detect of chemical and biological threats, spectroscopy has recently been used. Among them, Raman spectroscopy has been widely used for non destructive detection of specific molecules analysis of chemical and biological threats in glass, gottles, or air. However it is very difficlut to detect trace sample by using Raman spectroscopy due to its low sensitivity. To overcome this problem, surface-enhanced Raman spectroscopy (SERS) has been applied due to its considerable potential in highly selective and sensitive detection. SERS is a well known analytical technique, which can achieve extremely low detection limits of analytes and can provide a huge amount of fingerprint information of the individual component of mixtures. In this study, we detected the hydrazine and B.cereus using SERS. Details on SERS spectra of chemical and biological treats and their quantitative analysis will be discussed in this presentation.


SERS substrates based on Au@Ag nanorods for the detection of extremely diluted solutions

Murilo Pastorello, Fernando Aparecido Sigoli, Italo Odone Mazali

Institute of Chemistry - UNICAMP, Brazil; murilopastorello@gmail.com

This work presents the detection of probe molecule 4-aminobenzothiol (4-ABT) in extremely diluted solutions by Surface-Enhanced Raman Spectroscopy (SERS), using substrates based on core-shell nanorods, with gold on the core, and silver on the shell. Nanoparticles were deposited onto modified glass slides, followed by the deposition of the molecule of interest. SERS spectra were collected in the form of maps consisting of aproximately 150 spectra per sample, and using 633 nm excitation source. Bands attributed to the molecule could be identified in substrates prepared with solutions of concentrations up to 10-13 mol L-1.


Vibrational studies of steroid hormone and anti-cancer drug

Mukunda M. Borah, Th. Gomti Devi

North-Eastern Regional Institute of Science and Technology(NERIST), India; tgdevi26@gmail.com

Fibroids and breast cancer are human related diseases which are of major concern in today’s world. Estradiol is a hormone which is indirectly responsible for such type of dreadful disease due to its nature of cell proliferation in uncontrollable manner and Tamoxifen is an anti cancer drug for the breast cancer. We hope that study of these two molecules can unveil the properties of these molecules and their interacting environment. In the present study the vibrational properties of Estradiol and Tamoxifen molecules have been studied using spectroscopic techniques such as FTIR and Raman respectively. The optimized geometrical structure and vibrational frequencies of the molecules have been computed using ab-initio method. The basis set has been taken as HF/6-31G(d,p). Most of the stretching vibrational frequencies of the molecules could be assigned. The theoretical and experimental vibrational data are compared and found in good agreement with each other.


Reproducible SERS intensity of 4-aminobenzenethiol on AuNP-chitosan and its dependence on the nanoparticles deposition

Italo Odone Mazali1, Elias de Barros Santos2

1Institute of Chemistry - UNICAMP, Brazil; 2Institute of Science and Technology, Federal University of São Paulo, São José dos Campos -SP; mazali@iqm.unicamp.br

In this work, it was prepared substrates of gold nanoparticles, synthesized using chitosan as reducing and capping agent (AuNP-Chit), varying the number of depositions (1 to 10 depositions, 10D) on SH-modified glass slides. TEM analysis showed an average size distribution of the AuNP-Chit of ~20 nm. The AuNP-Chit substrates were tested 4-ABT as Raman probe molecule, drop-drying 25 μL of 10-6 mol L-1 4-ABT solution on each substrate. The SERS were carried out using a laser at 633 nm and acquisition time of 10 s, using a Jobin-Yvon T64000 Raman spectrometer. Analyzing the SERS data obtained for all AuNP-Chit substrates, it was observed a dependence of the SERS signal on the depositions number of AuNP. The point-to-point reproducibility was confirmed in terms of relative standard deviation (RSD) of 17.2%, which was achieved only for the 10D AuNP-Chit, indicating that this number of depositions is the best condition for this substrate.


Fast and sensitive anthrax biomarker detection using SERS-based solenoid microfluidic sensor

Jinhyeok Jeon1, Rongke Gao1,2, Juhui Ko1, Jaebum Choo1

1Hanyang University, Korea, Republic of (South Korea); 2Hefei University of Technology, China; jeonjh1004@gmail.com

Poly-γ-D-glutamic acid (PGA) is closely associated with the pathogenesis of anthrax infection. Here, we report the application of an automated surface-enhanced Raman scattering (SERS)-based solenoid-embedded microfluidic device to the safe, fast and sensitive detection of anthrax biomarker PGA in human serum. Analysis is based on the competitive reaction between PGA and PGA-conjugated gold nanoparticles with anti-PGA-immobilized magnetic beads within a microuidic environment. Magnetic immunocomplexes are trapped by two yoke-type mini-solenoids arranged at the end of each channel. To confirm the feasibility of this solenoid chip for PGA detection, the SERS spectra from the different focus points along channel distance were collected. Finally, the SERS signal was measured by focusing the laser beam within each microfluidic channel. The limit of detection (LOD) of PGA in serum is estimated to be 100 pg/mL. We believe that the defined method represents a valuable clinical tool for the diagnosis of an anthrax-related diseases.


Testing New SERS Substrates for Biosensing of Endothelial Cells and their Dysfunction

Ewelina Wiercigroch1,2, Malgorzata Baranska1,2, Kamilla Malek1,2

1Faculty of Chemistry, Jagiellonian University, Poland; 2agiellonian Centre for Experimental Therapeutics, Jagiellonian University; malek@chemia.uj.edu.pl

Here we present our investigations on two SERS approaches: label-free sensitive detection of bio-environmental fingerprint originating from contributions of proteins, carbohydrates, lipids, and nucleotides interacting with the metal and designed for a specific chemical response label-nanotags to study diseases linked with function of endothelial cells. We also evaluated SERS features of titania and aluminia-based periodic nanostructure as substrates for further constructions of SERS sensors.


SERS and Information Visualization to Detect Trace Levels of Pharmacological Drug Dispersed in a Host Matrix Biomembrane Model

Pedro Henrique Benites Aoki1, Ricardo Flavio Aroca2, Fernando Vieira Paulovich3, Osvaldo Novais Oliveira Jr.3, Carlos José Leopoldo Constantino1

1UNESP, Brazil; 2University of Windsor, Canada; 3USP, Brazil; case@fct.unesp.br

SERS spectral data is obtained for a biochemical system formed by a homogeneous distribution of the pharmacological drug methylene blue (MB, cationic SERS probe), which is electrostatically attached to a Langmuir monolayer host matrix of the anionic phospholipid DPPG at the air/water interface.

The DPPG monolayer is widely applied as simple-model of biomembrane, and different degrees of doping are attained by controlling the concentration of MB dissolved in the subphase. MB exhibits a high cross section for SERS and is commonly applied in photodynamic therapy for treating tumor cells, viruses and bacteria.

Micro-Raman maps are recorded for a series of MB concentrations down to one molecule, on average, in the field of view of the microscope objective. For data analysis, we implement a computational method (information visualization) to extract, in real time, the SERS data that can be assigned to single molecule spectra.

Acknowledgments: FAPESP, CNPq and CAPES


Rapid detection of Volatile Organic Compounds of Green Chinese Onion using Headspace Combined with SERS

minzhen si, jiawang li, lun li, chuanyun zhang, deqing zhang

Chuxiong Normal University, China, People's Republic of; siminzhen@cxtc.edu.cn

The SERS spectrum of volatile organic compounds of green Chinese onion and the SERS spectrum of the mixture of liquid 1-Propanethiolate and allyl methyl sulfide had been obtained . The results showed that the repeatability of SERS spectrum of volatile organic compounds of green Chinese onion was very good. And the SERS spectrum of volatile organic compounds of green Chinese onion mainly consists of 1-Propanethiol and allyl methyl sulfide.


Thiolated Rhodamine Dyes as Raman Reporters for SERS nanotags

Svetlana Brem, Sebastian Schlücker

University Duisburg-Essen, Germany; svetlana.brem@uni-due.de

Surface-enhanced Raman scattering is widely used in nanodiagnostics for the selective detection of biomolecules with nanotags conjugated to target-specific ligands such as antibodies or oligonucleotides. SERS nanotags comprise Raman reporters adsorbed on the surface of noble metal nanoparticles. Their brightness depends on the scattering cross section of both the plasmonic nanoparticle and the Raman reporter molecule.


RAMAN, SERS, SHINERS AND THEORETICAL STUDY ON THE INDIGO Ag SURFACE INTERACTION

Guillermo Corales1, Freddy Celis2, Sebastián Gutiérrez3, Juan Sebastian Gomez2, Marcelo Campo-Vallete2, José Javier Carcamo-Vega3

1Departamento de Química, Facultad de Ciencias, Universidad de Tarapacá, Arica, Chile.; 2Laboratorio de Espectroscopía Vibracional, Facultad de Ciencias, Universidad de Chile, Santiago, Chile.; 3Laboratorio de Análisis e Investigaciones Arqueométricas (LAIA), Museo arqueológico San Miguel de Azapa, Universidad de Tarapacá, Arica, Chile.; jcarcamo@uta.cl

The Raman spectroscopy and the SERS1 and SHINERS2,3 techniques allowed identify indigo and to infer about the analyte-Ag surface interaction and on the mechanisms involved in the Raman signals enhancement. The SERS spectral profile compared to that observed in Raman indicates that the indigo/Ag interaction is governed by the electromagnetic and chemical mechanisms; moreover, indigo is oriented nearly plane parallel to the Ag surface, involving the N and O atoms. The SHINERS spectra, where only an electromagnetic indigo/Ag interaction is permitted, resulted consequently similar to the Raman spectrum. The spectral SERS/SHINERS bands intensity differences indicate that indigo is not equally oriented on the SiO2 coated and uncoated Ag surfaces. Theoretical data support the indigo/Ag interaction proposition.



SERS SPECTRUM OF ARCHAEOLOGICAL TEXTILES DYES FROM NORTHERN CHILE

Elard Dauelsberg1, Yasmin Pérez1, Elizabeth Sanhueza1, Marcelo Campo-Vallete2, Marcela Sepulveda-Retamal3, Sebastian Gutierrez-Vivanco3, José Cárcamo-Vega3

1Departamento de Química, Facultad de Ciencias, Universidad de Tarapacá, Arica, Chile.; 2Laboratorio de Espectroscopía Vibracional, Facultad de Ciencias, Universidad de Chile, Santiago, Chile.; 3Laboratorio de Análisis e Investigaciones Arqueométricas (LAIA), Museo arqueológico San Miguel de Azapa, Universidad de Tarapacá, Arica, Chile.; jcarcamo@uta.cl

Surface-Enhanced Raman Scattering (SERS)1 is a powerful analytical technique allowing identify dyes in archaeological and historical textiles2. However, to register a SERS spectrum directly on archaeological textile samples requires a strict protocol of sample preparation and measurement. In this work, we present the SERS spectrum of dyes in archaeological textiles, registered from samples prepared from different methodologies: 1) dye extraction from chemical methods, 2) direct deposition of metal colloids on textiles and 3) deposition of colloids on textiles previously washed with a non ionic detergent. Present results demonstrate that samples obtained from methods 1 and 3 are highly adequate to acquire SERS spectra of dyes in archaeological textiles (Fig. 1). In addition, alizarin was identified as one of the dyes used in pre-Hispanic times.


WeP-P-IIB: Resonance Raman

Time: Wednesday, 17/Aug/2016: 5:00pm - 7:00pm  ·  Location: Exhibition Hall

High pressure resonance Raman spectroscopy study of linear carbon chains confined in double-walled carbon nanotubes

Wellington de Queiroz Neves1,2, Abraão Cefas Torres Dias1, Rafael Silva Alencar1, Nadia Ferreira Andrade3, Yoong Ahm Kim4, D. Kim4, Antonio Gomes Souza Filho1

1Departamento de Física, Universidade Federal do Ceará, Fortaleza, Ceará, 60455-900 Brazil; 2Instituto Federal de Educação, Ciência e Tecnologia do Ceará IFCE, Caucaia, Ceará, 61609-090 Brazil; 3Instituto Federal de Educação, Ciência e Tecnologia do Ceará IFCE, Tianguá, Ceará, 62320-000 Brazil; 4School of Polymer Science and Engineering, Chonnam National University, 77 Yongbongro, Gwangju, 500-757, Korea; wellington@fisica.ufc.br

In the present work, we study the high pressure effect on chains confined in double-walled carbon nanotubes (Cn@DWCNT). By comparing to the Cn@MWNT system, our results show that the chain mode also undergoes a non-linear shift to lower frequencies with the increase of pressure. This observation is explained by the increasing of the triple bonds of the chains (C≡C). We observe a downshift of ~ 27 cm-1 up the limit of 10 GPa, which is larger than that experimented by the longer chains within the MWCNT. This indicates that the weakening of the bonds (C≡C) is more significant for short chains when compared with long chains. However, in contrast with the observed in Cn@MWCNT system, the Cn@DWCNT shows reversibility up to 10 GPa, thus indicating that there are no pressure-induced formation of inter-chain links.


Asymmetry in Raman Excitation Profiles of Carbon Nanotubes: The Role of Excitons

Bruno Gondim de Melo Vieira, Eduardo Bedê Barros

Federal University of Ceará, Brazil; bruno@fisica.ufc.br

In this work, we investigate the asymmetry between G band incident and scattered resonance intensities of carbon nanotubes, which was verified recently by analyzing their resonance Raman excitation profiles (REPs) [1,2]. To accomplish this investigation, we improve the model of Hároz et al. by applying more careful calculations for the excitons and the exciton-phonon coupling [2]. The excitonic energies and eigenstates are calculated by solving the Bethe-Salpeter equation through the GW method within a Tight-Binding approach [4–6]. The exciton-photon and exciton-phonon coupling are determined according to the method developed by Jiang et al [7]. Finally, the nanotubes REPs are calculated within the 5th order model proposed by Hároz et al. [2]. Such accurate calculations are crucial to attest the effectiveness of this fifth-order Raman model in reproduce the asymmetric REP line shapes as well as verify the role of excitons by explicitly accounting for the excitonic dispersion.


A Resonance Raman and Computational Study of Ruthenium(II) Complexes with Substituted Dipyrido[3,2-a:2’,3’-c]phenazine Ligands

Georgina Ellen Shillito1,2, Christopher B. Larsen1,2, James R. W. McLay1, Nigel T. Lucas1,2, Keith C. Gordon1,2

1University of Otago, New Zealand; 2Macdiarmid Institute for Advanced Materials and Nanotechnology, New Zealand; shige777@student.otago.ac.nz

Ru(II) polypyridyl complexes have attracted considerable interest due to their versatile and manipulable photophysical properties, making them potential candidates for a range of commercial applications. However, a detailed understanding of these properties is paramount in order to develop effective and commercially viable materials. Systematic structural modification and subsequent analysis of the resulting electronic changes can further our understanding of these systems and potentially provide means by which to optimise commercially desirable features.

This presentation will discuss the results of systematic alteration of the linker unit in a Ru(II) polypyridyl donor-acceptor complex. A range of linker units were studied which allowed exploration into how communication between the triarylamine (TAA) donor and the dipyrido[3,2-a:2',3'-c]phenazine (dppz) acceptor is perturbed by distance, as well as by steric and electronic effects. The electronic properties of these systems were characterised using resonance Raman spectroscopy in conjunction with computational methods.


An usefull MatLab toolbox for the single-walled carbon nanotube characterization based on Ressonance Raman and optical absorption spectroscopies

Janaina Fernandes, Rafael Gontijo, Ariete Righi, Marcos A Pimenta, Cristiano Fantini

UFMG, Brazil; janarfer@gmail.com

The production of chirality enriched samples is of great interest for the development of new SWNT based technologies. However, to obtain a diameter distribution curve of a given sample, one should get a huge amount of Raman spectrum in a large number of excitation energies that demand expensive equipment and a lot of time.

In this work, a Matlab toolbox with a graphical user interface (GUI) was developed for the analysis of experimental data obtained by RRS and optical absorption for a large set of samples with different diameter distributions. This GUI utilizes camparisons between simulations based on theoretical models of dummy homogeneous samples and actual Raman spectra of the radial breathing modes[1]. This provides, in most cases, a curve of the diameter distribution with a very reduced number of excitation energies, and a quantitative curve of this distribution can be obtained by inserting the optical absorption spectra.


Resonance Raman Spectroscopy in Twisted Bilayer Graphene

Eliel Gomes Silva Neto1, Henrique Ribeiro2, Ariete Righi1, Cristiano Fantini1, Kentaro Sato3, Riichiro Saito4, Po-Wen Chiu5, Marcos Assunção Pimenta1

1UFMG, Brazil; 2Mackgraph, Universidade Presbiteriana Mackenzie, Brazil; 3Sendai National College of Technology, Japan; 4Department of Physics, Tohoku University, Japan; 5National Tsing Hua University, Taiwan; elielgsn@gmail.com

The interest in 2D materials has increased in the last years, and nowadays the focus is making van der Walls devices by stacking 2D material layers. This comes with a challenge to understand this stacking effect, and how it modulates electronic and optical properties. One of those systems is two graphene layers with an angle mismatch known as twisted bilayer graphene (TBG). In our work we use resonance Raman spectroscopy to study the mismatch effect in TBG. Our goal is to show the resonance behaviour of two observed peaks, the G band and the peak that appears around 1460 to 1520 cm-1, associated to phonons of TO branch of graphene. We obtain for the first time the Raman resonance profile of G and TO branch for a group of samples.


Quantifying (n,m) species in single-wall carbon nanotubes dispersions by combining Raman and optical absorption spectroscopies

Rafael Nunes Gontijo, Gustavo de Almeida Guimarães Sáfar, Ariete Righi, Marcos Assunção Pimenta, Cristiano Fantini

UFMG, Brazil; rafa.nunesgontijo@gmail.com

In this work, sorted samples of (6,5) and (7,6) suspended single wall carbon nanotubes made by column chromatography are characterized by Resonant Raman spectroscopy and optical absorption. We use Raman spectroscopy to get the relative concentration between the species in the samples and move to optical absorption to get the molar concentration and oscilator strength of each species for the samples. It is also shown the dispersive behavior of the 2D band for (7,6) tubes, showing that the band is composed but constant frequency peaks regardless of the laser line.


Spectroelectrochemical Investigation of the one-electron reduction of non-planar Nickel(II) Porphyrins

Julian Schindler1,2, Stephan Kupfer1, Linda Zedler1,2, Maria Wächtler1,2, Stefanie Gräfe1, Mathias O. Senge3, Benjamin Dietzek1,2

1Friedrich-Schiller-University Jena, Germany; 2Leibniz Institute of Photonic Technology Jena, Germany; 3Trinity College Dublin, The University of Dublin, Ireland; stephan.kupfer@uni-jena.de

Metalloporphyrins play a vital role in electron-transport chains of biological processes and occur transiently as reduced/oxidized species, which motivates investigations of their electrochemistry and the change in their (optical) properties upon reduction/oxidation. Our investigation focuses on a series of Nickel(II) porphyrins; such metalloporphyrins are not fully stable in aprotic solvents and consequently an electrochemical side reaction is observed upon double reduction. However, for the present metalloporphyrins the formation of an unknown by-product is already observed upon single reduction depending on the substitution pattern. To elucidate the nature of this unknown by-product and the influence of the structural variations on its formation upon single reduction, we present a combination of spectro-electrochemical (SEC) experiments and quantum chemical simulations. The computational prediction of UV-vis absorption and resonance Raman spectra allowed the identification of the unknown species formed upon single reduction and enabled to unravel the mechanism leading to the formation of the by-product.


Ressonant Raman Spectroscopy study of controlled doping WSe2

ELINEI SANTOS1, Waldeci Paraguassu1, Cristiano Fantini2

1Universidade Federal do Pará, Brazil; 2Universidade Federal de Minas Gerais, Brazil; elinei@ufpa.br

The WSe2 is a transition metal dichalcogenide (TDM) family of graphene-like layred inorganic structure. This structure makes it behaves as a semiconductor that shows a transition from an indirect band gap in the bulk to a direct gap for a monolayer. These characteristic with the stronger spin-orbit coupling in these material has stimulated basic research aiming at applications in optoelectronic. The Raman spectra of WSe2 sample are strongly dependent on the excitation energy. This novel material belong to symmetry point group D3h and exhibit a total nine-phonon branch. Three zone-center modes (q=0) are Raman active. We use group theory to characterize the vibration modes and investigated how theses modes changes with different excitation energy and doping in the structure of WSe2. We compare the modes trough group theory and Raman technique. We use Resonant Raman Spectroscopy to enhance the intensity of Raman peaks this way we could observe first and second-order Raman features [3].

[e1]


Coherent Anti-Stokes Raman Spectroscopy (CARS) in Two Dimensional Materials

Lucas Lafetá1, Alisson Cadore1, Thiago Grasiano1, Kenji Watanabe2, Takashi Taniguchi2, Leonardo Campos1, Ado Jorio1, Leandro Malard1

1Universidade Federal de Minas Gerais, Departamento de Física, Brazil; 2National Institute for Materials Science, Tsukuba, Ibaraki, 305-0044 Japan; lucas_bim18@hotmail.com

CARS is a nonlinear optical effect that occurs when the energy difference between two incident waves is equivalent to the energy of a phonon mode. This effect implies the incidence of a Pump and Stokes lasers, this generates the emission of photons at the Anti-Stokes frequency whose intensity is enhanced compared to linear Raman spectroscopy. In this study, we used samples monolayer graphene and few layers of hexagonal boron nitride (h-BN) to study its CARS response. For the case of h-BN was observed an increase in intensity of anti-Stokes signal when the energy difference between the lasers matched with the phonon energy of h-BN (1365cm-1). However, graphene samples we observed a decrease of the signal when the energy difference between the lasers coincided with the phonon energy of the graphene (1590cm-1). We will address the causes for the observation of this phenomenon based on different electronic structures of these materials.


Stokes and anti-Stokes temporal quantum correlation in Raman Scattering

Filomeno Soares de Aguiar Júnior1, Mark Kasperczyk2, Cassiano Rabelo3, Lukas Novotny2, Ado Jorio1

1Departamento de Física, Univ. Federal de Minas Gerais, Belo Horizonte, MG, 31.270-901, Brazil; 2Photonics Laboratory, ETH Zurich, 8093 Zurich, Switzerland.; 3Programa de Pós-Graduação em Engenharia Elétrica, Universidade Federal de Minas Gerais, Belo Horizonte, MG 31.270-901 Brazil; fsa.juniorfisicaufv@gmail.com

In this work we study the correlated Stokes and anti-Stokes Raman scattering process, called here SaS. The SaS, is an effect where the same phonon participates in the Stokes and anti-Stokes scattering processes. The SaS process has not been considered in current treatments of Raman scattering and can bring changes in the use Raman spectroscopy for local temperature measurements. Furthermore, these photons can arise as an important source of correlated photon pairs, widely used in quantum information, for example, in the implementation of the quantum memory.



WeP-P-IIC: Pharmaceuticals/Biomolecules

Time: Wednesday, 17/Aug/2016: 5:00pm - 7:00pm  ·  Location: Exhibition Hall

Amorphous Raloxifene Hydrochloride investigated by Raman Spectroscopy

Yara Santiago de Oliveira, Alejandro Pedro Ayala

Federal University of Ceará, Brazil; yara@fisica.ufc.br

Raloxifene Hydrochloride (RLC) is a derivative benzothiophene used for treatment of osteoporosis, with aqueous solubility of 627.4 µg/mL.There are many strategies to improve the solubility and one of them is to use the amorphous form of active pharmaceutical ingredients.This work aims to provide an alternative to the pharmaceutical industry to circumvent this problem.The relationship and interconversion between the new form and the raw material were investigated by several methods, such as Raman spectroscopy as a function of temperature, that allowed identifying the amorphous form, as for example wider bands at room temperature when compared with those the crystalline RLC, being better evidenced by the wide band around 1590 cm-1, related to the C=C stretching of the aromatic rings, which is split in the crystalline form.This way Raman spectroscopy was used to discriminate amorphous and crystalline forms of RLC, and this result was supported by powder X-ray diffraction and thermal analysis.


Stability Study of Ceftazidime Pentahydrate by Raman Spectroscopy

Maria Silmara Alves de Santana, Jéssica de Castro Fonseca, Alejandro Pedro Ayala

Universidade Federal do Ceará, Brazil; silmara@fisica.ufc.br

Ceftazidime (CTZ) is an antibiotic that has many indications, including the treatment of lower respiratory tract. Then this study aims to investigate the stability of the CTZ.5H2O by different methods, such as powder x-ray diffraction (PXRD), thermal analysis and Raman spectroscopy with temperature variation. In this sense, using the multivariated curve resolution method it is possible to infer that as the temperature increased the first process is observed at 78.4°C, and as was verified in thermal analysis and PXRD with temperature variation this process corresponds to the release of four molecules of water and a second process with new spectroscopic changes was verified at 125°C and it was associated with the release of one molecule of water, this way obtaining the anhydrous form of the drug. In order to support the Raman study the other techniques previously cited were used, confirming this result.


Thermal stability and polymorphism of Secnidazole studied by vibrational spectroscopy

Beatriz Pinheiro Bezerra, Jéssica Castro Fonseca, Yara Santiago de Oliveira, Alejandro Pedro Ayala

University Federal of Ceara, Brazil; beatriz@fisica.ufc.br

Secnidazole is an antimicrobial agent used against some anaerobic bacteria and parasites, is commercialized as a hemihydrate, being stable at room temperature, but showing relevant phase transitions on heating. Raman spectroscopy was successfully applied to the study of hydrate-anhydrous conversion in pharmaceuticals, as well as, in the identification of drug polymorphs. Considering its key features for the solid-state characterization of pharmaceutical compounds, in this contribution, Raman spectroscopy was applied in combination with hot-stage microscopy, X-ray powder diffraction and thermal analysis to provide a comprehensive description of the structural modifications involving the hydrate of SZN and its transformation into the anhydrous form.


A Comparison Analysis of Infrared Spectrum to Three Kinds of Alpinia Japonica Powder

Jia-wang Li, Yan Liu, Min-zhen Si

Chuxiong Normal University, China, People's Republic of; 509942900@qq.com

In this paper, a comparison analysis of infrared absorption spectrum has been done to three kinds of Alpinia Japonica powder. The tuberous root of Alpinia Japonica powder contains protein (amino acid), gingerols and diarylheptanoids,monosaccharide and polysaccharides (including starch). The most of type of the chemical composition of three Alpinia Japonica sugar is the same, but the relative content of different kinds of sugar have certain differences. The protein content of β- Angle configuration to three kinds of Alpinia Japonica is approximately equal. The protein content of β-Angle configurations to Alpinia guinanensis D. Fang et X. X. Chen is higher,β- folding conformations to Alpinia platychilus K. Schum is higher.


Synthesis, Vibrational spectra and DFT calculations of chalcone derived from 2-hydroxy-3,4,6-trimethoxyacetophenone

Valéria Nunes Lima1, Alexandre Magno Rodrigues Teixeira1, Hélcio Silva Santos2, Paulo Nogueira Bandeira2, Beatriz Gonçalves Cruz1, Diniz Maciel Sena Junior1, Paulo de Tarso Cavalcante Freire3

1Regional University of Cariri, Crato-CE, Brazil; 2State University Vale do Acaraú, Sobral-CE, Brazil; 3Federal University of Ceará, Fortaleza-CE, Brazil; alexandre.teixeira@urca.br

Croton is a large genus of Euphorbiaceae, comprising around 1300 species, of which 700 are native plants from Brazil. One of these species is the Croton anisodontus, an endemic species native to the caatinga of Northeast Brazil. Ethnopharmacological information refers to the compound 2-hydroxy-3,4,6-trimethoxyacetophenone derived from Croton anisodontus Müll as possessing antibacterial activity. In this work, we report the synthesis, characterization of chalcone (2E)-1-(2-hydroxy-3,4,6-trimethoxyphenyl)-phenylprop-2-en-1-one by Fourier Transform Infrared and Fourier Transform Raman spectroscopy. In addition, Density Functional Theory calculations were performed, using the Gaussian 09 package with the B3LYP functional and 6-31G(d,p) basis set, in order to gain some insight into the normal modes of the material. Calculated wavenumbers were found to reproduce the experimental ones with good agreement, allowing the assignment of the normal modes present in the FT-IR and FT-Raman spectra of (2E)-1-(2-hydroxy-3,4,6-trimethoxyphenyl)-phenylprop-2-en-1-one crystal. The assignment of the normal modes were carried out by means of potential energy distribution.


Spectral and Computational Studies of O-Tolyl Biguanide

V. Bena Jothy

Women’s Christian College, Nagercoil, India; benaezhil@yahoo.com

Structure of the antibiotic and antimicrobial compound O-Tolyl Biguanide (OTB) was confirmed by Powder XRD study and DFT quantum chemical computations performed at B3LYP/6-311++G(d,p) level. FT-IR and FT-Raman spectra of OTB were recorded and vibrational assignments of the observed fundamental bands have been assigned with the aid of NCA.


Study of hydrogen bonding and chemical reactivity of cocrystal of paracetamol and bipyridine

Karnica Srivastava1, Manishkumar R Shimpi2, Poonam Tandon1, Kirti Sinha1, Sitaram P Velaga2

1UNIVERSITY OF LUCKNOW, India; 2Luleå University of Technology, S-971 87, Luleå, Sweden; karnica.6@gmail.com

Paracetamol (N-acetyl-p-aminophenol) is widely used as the counter analgesic and antipyretic drug [1,2] to treat in many problems such as headache, muscle aches, fevers. Paracetamol has two well known polymorphic forms, monoclinic and orthorhombic. We have studied the cocrystal of orthorhombic form of paracetamol (PRA) as API and bipyridine (BPY) as coformer.

The purpose of this work is to examine the ability of methods to perform detailed characterization of cocrystal of Paracetamol and bipyridine and to check the interaction between them. The FT-IR and FT-Raman spectra of API, coformer and cocrystal (PRA-BPY) have been recorded and analyzed. The optimized geometry, total energy, potential energy surface and vibrational wave numbers have been determined using DFT/B3LYP method. The quantum theory of atoms in molecules (QTAIM) and natural bond (NBO) analysis are used to evaluate the strength and nature of hydrogen bonds. Chemical reactivity is evaluated using MEPS, HOMO-LUMO and Electronic reactivity descriptors.


Study of Electronic and Vibrational Spectra of Nitrofurantoin-4-Dimethylaminopyridine using DFT and QTAIM approach

ERAM KHAN1, POONAM TANDON1, VENU R VANGALA2, ALEJANDRO P AYALA3

1UNIVERSITY OF LUCKNOW, Lucknow, India; 2bCentre for Pharmaceutical Engineering Science, School of Pharmacy, University of Bradford, Bradford BD7 1DP, United Kingdom.; 3cDepartamento de Fisica, Universidade Federal do Ceará, Fortaleza, Ceará, Brazil.; eramkhan0786@gmail.com

Herein structural properties of co-crystal of nitrofurantoin (NF) with 4-Dimethylaminopyridine (DMAP) has been studied using quantum chemical calculations. NF is an antibacterial and is used to treat urinary tract infections [1].

The molecular structure, vibrational frequencies and energy of the optimized geometry of cocrystal, API and coformer were computed employing the quantum chemical methods. The calculations have been performed by DFT theory. The characterization of the cocrystal (NF-DMAP) and NF was done spectroscopically by employing FT-IR and FT-Raman techniques.

Natural bond orbital (NBO) analysis has been carried out to inspect the hydrogen bonds. Topological parameters were analyzed using ‘Atoms in Molecules’. Molecular electrostatic potential (MEP) has also been plotted for predicting the molecule reactivity towards positively or negatively charged reactants. HOMO-LUMO gap reveals that cocrystal is more reactive than API (Fig. 1). Global and local reactivity descriptors analysis has been performed.


Imaging of the biomarkers of atherosclerotic alternations in murine brain – IR and Raman studies

Karolina Chrabaszcz1, Kamila Kochan1,2, Barbara Szczur1,2, Edyta Maslak1, Jakub Dybas1,2, Katarzyna M. Marzec1

1Jagiellonian Centre for Experimental Therapeutics (JCET), Jagiellonian University; 2Faculty of Chemistry, Jagiellonian University; katarzyna.marzec@jcet.eu

In this work, taking advantages of complementary IR and Raman spectroscopies combined with chemometric analysis we studied the biochemical composition of the grey (GM) and white matter (WM), the general lipid fraction as well as differentiation of cholesterol and its esters for both, control (C57BL/6J) and ApoE/LDLR/‒ mice brain tissue with advanced atherosclerosis. The IR and RS results allowed us to calculate the lipid/protein ratio for atherosclerotic tissue for GM and WM. Raman microimaging allowed for spatial differentiation between crystalline cholesterol from other lipids, while IR results suggest an increase in the cholesterol fraction of atherosclerotic WM and a lack of (or only minor) change in the content of esters (including cholesterol esters and triglycerides). For GM, no significant increase in cholesterol was visible; however, increased triglyceride and/or cholesterol ester content was observed.



WeP-P-IID: Materials (nanoparticles, semiconductors)

Time: Wednesday, 17/Aug/2016: 5:00pm - 7:00pm  ·  Location: Exhibition Hall

Surface chemistry analysis of ultra-stable suspensions of nanocarbons by Raman and X-ray photoelectron spectroscopies

Romana Petry1, Camila A. Holanda1, Viviane M. Saboia1, Thiago R. R. Garcia1, Gislaine C. Padovani1, Amauri J. Paula1, Antonio G. Souza Filho2

1Solid-Biological Interface Group (SolBIN), Department of Physics, Federal University of Ceara; 2Department of Physics, Federal University of Ceara; romanapetry@gmail.com

In this work, we obtained ultrastable suspensions of oxidized carbon nanotubes(CNTs) and graphene oxide(GO) sheets with Pluronic F-127(PF127) and polyethylene glycol(PEG) 35,000, respectively, in a 0.9%(w/v) NaCl solution. To elucidate the mechanism of these colloidal stabilizations, we analyzed nanocarbons’ aspects such as their morphology, size and surface chemistry, which was obtained through the analysis of D and G band in Raman spectra and X-ray photoelectron spectroscopy(XPS) measurements, associated to the polymer features, such as chemical structure and stereochemistry. We observed an initial surface chemistry depending steric or electrosteric stabilization of CNTs, which high aspect ratio enables the nanotube wrapping by PF127 at low polymer concentrations (<0.1%wt). Regardless of their surface chemistry features, depletion stabilization for CNTs occurs at higher PF127 concentrations (≥1%wt), leading to ultra-stable colloids. Futhermore, GO sheets could only be stabilized in the presence of high concentrations of PEG 35,000 (5%wt), through manifestation of repulsive depletion forces.


Characterisation of reduced Graphene Oxide/Polyaniline gels prepared by in situ chemical reduction

Claudio Hanashiro Barbosa Silva1, Maria Iliut2, Aravind Vijayaraghavan2, Marcia Laudelina Arruda Temperini1

1Institute of Chemistry, University of São Paulo, São Paulo, Brazil; 2School of Materials and National Graphene Institute, The University of Manchester, Manchester, United Kingdom; chbsilva@iq.usp.br

Graphene oxide (GO) is a graphene derivative which presents some advantages such as water dispersibility and chemical versatility. Such aspects are important for the development of novel hybrid materials for different fields which do not demand the electric and mechanical properties of pristine graphene. We report here the characterisation of hybrid materials prepared by the association of GO and polyaniline (PANI), a conducting polymer, and in situ chemical reduction of GO. The materials were also characterised by infrared absorption and X-ray photoelectron spectroscopies and scanning electron microscopy. Surface properties of the hybrid materials will be correlated to structural and morphological aspects.


Raman studies of the interactions of carbon nanocomposite layers with fibrinogen

Aleksandra Weselucha-Birczynska1, Ewa Stodolak-Zych2, Krzysztof Morajka1, Elżbieta Długoń2, Maria Dużyja1, Tomasz Lis2, Maciej Gubernat2, Marta Błażewicz2

1Jagiellonian University, Poland; 2AGH-University of Science and Technology, Poland; birczyns@chemia.uj.edu.pl

We are investigated two types of carbon nanocomposites for potential medical applications. The first material has been created on the titanium support covered with bioactive layers of MWCNT deposited by electrophoretic (EPD) method and then by thin film of pyrolytic carbon introduced by chemical vapor deposition (CVD) process. The second material was formed from carbon nanofibers prepared via electrospinning of polyacrylonitrile (PAN) precursor with following carbonization and then coated with pyrolytic carbon (CVD). The reaction of the blood protein is crucial in the evaluation of biocompatibility of implant material not only those which are intended to come into contact with blood. To get to know materials structure and properties, in relation to their applications, the adsorption of fibrinogen, protein involved in coagulation or platelet adhesion, was studied. We have observed the influence of surface nano and micro topography on the cellular response, modelling adhesion with fibrinogen.


STUDY OF NON-GRAPHITIC CARBON OF BIOMASS MATERIALS BY RAMAN SPECTROSCOPY

ENRIQUE RONALD YAPUCHURA1, FRANCISCO G. EMMERICH1, JAIR C. C. FREITAS1, ERLON H. MARTINS-FERREIRA2

1UNIVERSIDADE FEDERAL DO ESPIRITO SANTO, Brazil; 2DIVISÃO DE METROLOGIA DE MATERIAIS - DIMAT, INMETRO, RJ, Brazil; enrique.r.yapuchura@gmail.com

The endocarp of babassu coconut (EBC) and rice hulls (RH) are two kinds of biomass with an unusually high concentration of silicon dioxide. Large structural changes are produced in these non-graphitizable carbonaceous materials when it is heat treatment up 2200 °C and 1400 °C respectively. The ratio between the integrated intensities of the disordered-induced D and G Raman bands ID/IG obtained in the samples of EBC and RH and Full Width at Half Maximum (FWHM) of the G band as a function of the crystallite size La are analyzed in this work. Moreover, we have studied the transformation of Si02 into silicon carbide (SiC) that takes place in this material in the heat treatment temperatures range of 1200-140 °C Raman imaging.


Raman and Infrared Investigation of Sodium and Potassium Exchangeable Titanates Nanoribbons

Fábio Lacerda Resende Silva1, Karla Balzuweit1, Jean-Louis Bantiginies2, Ariete Righi1

1Universidade Federal de Minas Gerais, Brazil; 2Université de Montpellier II; fabio_lrs@hotmail.com

The research in titanates and titania nanomaterials have been motivated by their potencial in several technological applications, as example, dyes and radioactive ions adsorption, photocatalysis and batteries. The success of these materials in such applications depends on the exchange capacity, stability and morphology. Nanotitanates with high surface area with tube and ribbon morphology can be easily synthesized threating hydrothermally titanium dioxide in alkaline medium. Nevertheless, the vibrational and structural properties of these materials are still under great debate.

In the present investigation, we produced titanates nanoribbons by hydrothermal method using anatase titanium dioxide and sodium and potassium hydroxide aqueous solutions as alkaline medium. The resulting samples were treated to induce different amounts of Na-H and K-H exchange. After that, they were treated to induce the H-K and H-Na exchange. The physical propperties have been investigated by electron microscopy, XRD, atomic absorption spectroscopy and Raman and IR spectroscopy.


Additional Raman modes in ZnO and Eu0.01Zn0.99O nanoparticles synthesized by solution combustion method

T.J. Castro1,2, S.W. da Silva1, A. Franco Jr.3, H.V.S. Pessoni3, P.C. Morais1,4

1University of Brasília, Institute of Physics, Brasília DF 70919-970, Brazil.; 2Federal Institute of Education, Science and Technology of Brasília, Brasília DF 72146-000, Brazil; 3Federal University of Goiás, Institute of Physics, Goiânia Go 74001-970, Brazil; 4College of Chemistry and Chemical Engineering, Anhui University, Hefei 230601, China.; tiago.castro@ifb.edu.br

Zinc Oxide is an extremely studied material due to its unique physical properties, especially wide direct band gap and large exciton binding energy. However, there are some points under discussion, which include the origin of five additional Raman modes (AMs) frequently verified in N-doped ZnO. In this work, we use Raman spectroscopy to investigate the presence of nitrogen in ZnO and Eu0.01Zn0.99O nanoparticles synthesized by solution combustion method. The as-produced nanoparticles exhibited the characteristic color and the AMs typically found in N-doped ZnO. Nevertheless, nitrogen was not verified by EDS spectroscopy. The extra features disappeared after annealing in air, but continued after calcination in N2 and He flow. This behavior indicates that Zni - Oi complexes cannot be the origin of the ~510 cm-1 additional mode, as currently proposed in literature. The presence of these AMs can be attributed to disorder activated Raman modes favored by nitrogen doping.


In-situ Raman scattering of Non-Graphitizing Carbons under Room-Temperature Compression

Olga Maslova1,2,3, M. Medre Nobrega4, M.R. Ammar5, C. Fantini Leite1, M. A. Pimenta1

1Universidade Federal de Minas Gerais, Brazil; 2Southern Federal University, Rostov-on-Don, Russia; 3Tomsk State University, Tomsk, Russia; 4Universidade de Sao Paulo, Sao Paulo, Brasil; 5CNRS, CEMHTI UPR 3079, Université d´Orléans, Orleans, France; o_maslova@rambler.ru

High-temperature pyrolysis of graphitizing carbons is known to induce their graphitization at a large (more than 1 µm) local molecular orientation (LMO) of the precursor. However, graphitization can even arise in non-graphitizing carbons via applying pressure which causes microtextural and structural transformations therein. This work is thus dedicated to in-situ studies under pressure of non-graphitizing carbons by an example of synthesized saccharose-based cokes (SC) which exhibit a microporous structure even after annealing at high temperatures to 2500°C. Here, pressure is expected to transform the microporous microtexture towards a lamellar one typical of graphite. To compare the hydrostatic pressure effect on their microstructure with graphitizing carbons, we examine the anthracene-based cokes (AC) possessing a lamellar structure via combination of Raman spectroscopy and X-ray diffraction in order to carefully probe the structural modification in these materials under extreme conditions.


Advanced microscopies for studying carbon-based hibrid nanomaterials

Luis A. PEREZ, Gabriela LACCONI

INFIQC- Dto. Fisicoquimica. Facultad Ciencias Químicas, UNC, Córdoba- Argentine Republic; glacconi@mail.fcq.unc.edu.ar

The combination of carbon-based materials (graphene, graphene oxide, protein assemblies, etc.) with metallic nanostructures and silicon, to obtain hybrid-materials is performed using simple chemical, electrochemical and photochemical methods. We show topographical features, optical and molecular properties of diverse hybrid systems, recorded with high spatial resolution by advanced microscopies (AFM-Raman, Imaging-Raman, SNOM, SERS, TERS, DRIFTS-contrast imaging, dark field imaging): -SERS platforms of AgNPs-protein assemblies for aminoacids detection. -Graphene oxide (GO) flakes decorated with AgNPs by using electrochemical strategies. -GO-rGO hybrid pattern. Lithographic designs engraved on glass and silicon by laser radiation induction on GO films. -Network of graphene(CVD)-AuNPs. Structural changes induced in graphene by the interaction with the TERS-tip evidence the reversible defects generation and the energy transfer from the hybrid structure to the Au-tip (blue shifts of bands). All nanohybrids materials are trustworthy substrates for precise SERS chemical analysis.


Structural characterization of p-doping and ion-implanted GaAs:Zn nanowires by Raman spectroscopy

Gregório Corrêa Júnior1,2, Waldomiro Paschoal Júnior2, Waldeci Paraguassu Feio2, Håkan Pettersson3,4

1Federal Institute of Education, Science and Technology of Pará, Brazil.; 2Post-graduation Program in Physics, Federal University of Pará, Brazil.; 3Department of Mathematics, Physics and Electrical Engineering, Halmstad University, Sweden.; 4Department of Solid State Physics, Lund University, Sweden.; gregfisjunior@gmail.com

In this work, we present the results of study of the Raman line-shape and band shift of the TO, SO and LO phonon modes in p-doping (GaAs:Zn) and Mn ion-implanted GaAs:Zn nanoeires (NWs). Our studies, in p-doping GaAs NWs, showed the presence of a band of defect (DF) situated close to TO phonon. In Mn ion-implanted GaAs:Zn NWs we observed a strong increase in this peak and a down-shift in SO phonon. At the same time, we show that the higher ion-implantation temperatures and subsequent annealing typically lead to higher doping levels in the semiconductor, but also segregation into MnAs clusters, that contribute to increase the NWs dielectric constant. We further measured the electrical resistance (R) and magnetoresistance (MR), at 1.6 K in GaAs:Zn NWs with Mn ion-implanted and annealed at temperature of 300 ºC and 350 ºC for 12 and 24 hours.


Stokes-Raman Scattering Analysis of Ecoflex Nanocomposites with copper nanoparticles: effect of size and concentration.

Manuel Melendrez Castro1, David Rojas1, Andres Jaramillo1, Alejandra Salgado1, Silvia Riquelme3, Alvaro Maldonado3, Ricardo Eulises Báez Cruz1,2

1Advanced Nanocomposites Research Group (GINA), Hybrid Materials Laboratoy (HML), Department of Materials Engineering (DIMAT), University of Concepcion, 270 Edmundo Larenas, Box 160-C, Concepcion 4070409, Chile; 2Department of Physics, Faculty of Physical Sciences and Mathematics, University of Concepcion, P.O. Box. 160-C, Concepcion, Chile; 3Biomaterials, Technological development Unit (UDT), Concepcion, Chile; rebaezc@unal.edu.co

In this work, it reported the vibrational activity Ecoflex nanocomposite biodegradable polymeric with nanoparticles copper (Cu-NPs). 4 substrates were analyzed by micro Raman spectroscopy, in which tree concentration of Cu-NPs (1%, 3% and 5%) were added to Ecoflex and Cu-NPs with different sizes (50, 100 and 200 nm) were used. The vibrations at 1278 cm-1 related to the bond H3C-OH were found; the sample had a higher vibration intensity at it frequency was 50nm_1% followed by 50nm_3% with a vibration intensity of 21.8%. Vibration associated to H2C=O was found at 1779 cm-1, at this frequency the sample 50nm_3% showed higher vibration with respect to the sample 50nm_1%, which had 50.4% of vibration intensity. It was found that sample 50nm_5% does not presented any vibration owing to the large amount of Cu-NPs that induce plasmon damping on Ecoflex.



WeP-P-IIE: Raman Instrumentation & Industrial Applications

Time: Wednesday, 17/Aug/2016: 5:00pm - 7:00pm  ·  Location: Exhibition Hall

Pharmaceutical Processing by Raman Spectroscopy Conjunction with Chemometrics

Jagdish Tewari

Biogen, United States of America; jagdish.tewari@biogen.com

Raman spectroscopy is a fast and non-destructive analytical technique that offers many advantages for a broad range in pharmaceutical processing. In this study we have used Raman spectroscopy conjunction with chemometics in pharmaceutical domain where we applied from raw material identification to final product. The characteristics of Raman spectroscopy allow the technique to be implemented as a process analytical technology (PAT) tool . Recent instrumental developments in Raman spectroscopy open the perspectives of numerous applications in the pharmaceutical processing.


Rapid identification of Paracetamol Tablets and Paracetamol Amantadine Hydrochloride and Chlorphenamine Maleate Capsules by portable Raman Spectrometer

Guiping Chen, Li Ma

Shimadzu (China) Co.,LTD. Shanghai Branch; sshcgp@shimadzu.com.cn

In this work, we try to discriminate the substances with similar spectra by Shimadzu RM-3000 without chemometrics. Figure 1 shows the Raman spectra of Paracetamol and Paracetamol Amantadine Hydrochloride and Chlorphenamine. Maleate. As it is shown in Figure 1, their spectra are so similar that the value of HQI (Hit Quality Index) is up to 0.96. But through careful observation, compared with the spectrum of Paracetamol, we can see that there are three peaks at 255~300cm-1, 525~570 cm-1 and 900~950 cm-1 from spectrum of Paracetamol Amantadine Hydrochloride and Chlorphenamine Maleate. Therefore, the identification of the two drugs was carried out by selecting the wavenumber ranges of 255~300cm-1, 525~570 cm-1 and 900~950 cm-1. By the time, the value of HQI is 0 so that we can distinguish them so easily, which indicated that Shimadzu RM-3000 can distinguish the substances with similar raman spectra without chemometrics at a certain extent.


Automated Raman for Particle and Trace Compound Analysis

Mark Sparrow1, Eunah Lee2, Sebastien Vergnole3

1RJ Lee Group, 350 Hochberg Road, Monroeville, PA 15146, USA; 2HORIBA Scientific, 3265 Scott Blvd., Santa Clara, CA 95054, USA; 3HORIBA Scientific, 231 rue de Lille, 59 650 Villeneuve D’Ascq, France; sebastien.vergnole@horiba.com

In 2012, the United States Occupational Safety and Health Administration (OSHA) adopted the United Nations (UN) Globally Harmonized System for Classification and Labeling of Chemicals (GHS). This ruling specifies the labeling criteria which must be used to describe the health and physical hazards associated products entering the marketplace. Given the reduction in regulatory limits for RCS and difficulties that exist with detecting trace crystalline silica using traditional methods, we propose an improved methodology using automated Raman analysis for discrete particulates allowing the detection of trace quantities of RCS within mineral matrices. We will present an application of this technique, combined with Computer-Controlled SEM (CCSEM) and X-ray diffraction, to create a new method capable of providing correlative analysis and more thorough characterization of trace mineral content in materials than was previously possible using stand-alone techniques.


Raman spectroscopy without spectrometer

Vladislav V. Yakovlev

Texas A&M University, United States of America; yakovlev@tamu.edu

We demonstrate shot-noise limited Raman signal detection using time-correlated photon counting without the use of a spectrometer.


IC Raman spectroscopy

Vladislav V. Yakovlev

Texas A&M University, United States of America; yakovlev@tamu.edu

We introduce a new paradigm in ultrasensitive Raman signal detection based on integrated cavity. The new platform demonstrates Raman signal enhancement by 6 orders of magnitude.


Spatially-offset Raman spectroscopy using a software-controlled digital micro-mirror device

Zhiyu Liao, Faris Sinjab, Ioan Notingher

University of Notthingham, United Kingdom; faris.sinjab@nottingham.ac.uk

We demonstrate a novel approach to spatially-offset Raman spectroscopy (SORS), utilizing digital micro-mirror devices (DMDs). SORS allows Raman spectra to be obtained deep within a highly scattering sample by measuring light at positions offset from the laser excitation. This is usually employed though custom fiber probes with ring-collection geometries, where the offset is fixed to certain values. This can be inflexible when a continuous range of offset are desired, and is not compatible with modalities such as microscope-based SORS.

A DMD is an array of programmable mirrors which can behave as an offset controller for SORS. We demonstrated a simple modification to a conventional Raman system, illustrating various ways the DMD can be used for SORS measurements of scattering polymer multilayers. We also show that this approach is particularly useful for improving the throughput and control of the emerging microscope-based SORS technique.


Raman spectroscopy for the detection of counterfeit stevia products

Paul Vargas Jentzsch1, Sonia Torrico-Vallejos2, Sonia Mendieta-Brito2, Vaneza P. Lorett Velásquez3, Cristian Buendía-Atencio3, Valerian Ciobotă4, Luis A. Ramos5

1Departamento de Ciencias Nucleares, Facultad de Ingeniería Química y Agroindustria, Escuela Politécnica Nacional, Quito, Ecuador; 2Center of Agroindustrial Technology (CTA), Faculty of Sciences and Technology, San Simón University, Cochabamba, Bolivia; 3Departamento de Química, Facultad de Ciencias Básicas, Universidad Antonio Nariño, Bogotá D. C., Colombia; 4Rigaku Analytical Devices, Berlin, Germany; 5Ecuadorian Agency for Quality Assurance in Agriculture (AGROCALIDAD), Tumbaco, Ecuador; paul_5151@yahoo.com

Stevia is a highly demanded sweetener that has gained relevance because it can be consumed by diabetic patients. The popularity of stevia has increased during the last years and, at the same time, counterfeit products have also appeared on the market. In order to protect the consumers, control institutions in each country need appropriate analytical techniques and methods that enable them to respond fast and efficiently, ideally, performing in situ verifications of the quality of products. The detection of counterfeit in stevia products is a proposed application of Raman spectroscopy. Commercial stevia extracts (powder) were measured using a portable Raman spectrometer and the resulting spectra were analyzed. Since stevioside and rebaudioside A are the most important components in authentic stevia products, a theoretical study on their Raman bands was also carried out.


A step ahead in on-line monitoring of biopharmaceutical manufacturing: Timegated Raman Approach

Mari Tenhunen1, Lauri Kurki1, Johanna Granda1, Jouni Takalo1, Martin Kögler2

1Timegate Instruments Oy, Finland; 2University of Helsinki; mari.tenhunen@timegate.fi

Biopharmaceutical production is intrinsically subject to variability. Continuous monitoring of process quality attributes would be desirable to allow timely process control and to improve process efficiency. Among the critical variables only a few are measured routinely, i.e. methods for online monitoring of process quality attributes are still in their early days.

Raman spectroscopy has shown very promising results for bioprocess monitoring task. However, the traditional continuous-wave Raman often suffers from the fluorescence signal decreasing the sensitivity of the measurement or preventing totally the detection of weak Raman signal.

New timegated Raman approach offers the solution to many current monitoring challenges in biopharmaceutical manufacturing. Through the timegating feature, it is possible to reduce these fluorescence issues. This presentation will include a more detailed description of this timegated Raman measurement approach, real measurement examples in lab and an outlook for the future implementation steps towards the on-line monitoring of biopharmaceutical manufacturing.


Terahertz Raman Spectroscopy : Instrumental Aspects and Preliminary Studies on Intermolecular Interactions

Amit Kumar Joshi1, Freek Ariese1,3, Siva Umapathy1,2

1Department of Inorganic and Physical Chemistry, Indian Institute of Science , Bangalore, India; 2Department of Instrumentation and Applied Physics, Indian Institute of Science , Bangalore, India; 3VU University Amsterdam, Netherlands, The; akj22akj@gmail.com

Spectroscopists using IR absorption or Raman scattering are focusing mostly on fingerprint vibrations, which are highly selective for individual functional groups. However, there are several different motions which fall in the category of collective vibrations or reflect weak intermolecular interactions. These vibrations are extremely low in energy (0.1-10 THz or 3-300 cm-1) and it is very difficult to detect them with traditional instrumentation.

We have developed a Terahertz Raman spectrometer based on Volume Bragg Gratings (VBGs) to detect these low-energy vibrational modes. The performance of the spectrometer was characterized using standard model compounds. Preliminary studies on binary mixtures of benzene and n-hexane show the effect of dilution on intermolecular (pi-pi) interactions. Computational studies have been performed to study different kinds of intermolecular interactions in the case of pure solvents as well as in binary mixtures.


Development of a multi-modal Raman-based microscope for the automatic diagnosis of the chronic lymphocytic leukemia

Olivier Piot1, Cyril Gobinet1, Abdellilah Beljebbar1, Valerie Untereiner2, Damien Gheldof3, Bernard Chatelain3, Michael Fere1, Louis Liu1, Martin Chollat4, Jacques Klossa4

1URCA - UMR CNRS7369 MEDyC, France; 2PICT University of Reims Champagne Ardenne; 3CHU Namur-Montgodinne, Université Catholique de Louvain; 4TRIBVN; olivier.piot@univ-reims.fr

In hematology, diagnosis of B chronic lymphocyte leukemia (CLL) is based on the microscopic analysis of cell morphology from patient blood smears. New technologies appear promising to facilitate and improve the early diagnosis and monitoring of personalized therapy. So, we develop a biophotonic solution based on Raman microspectroscopy.

Blood smears were prepared on conventional glass slides. In addition, data were also acquired on cell sorting samples of isolated T, B and NK lymphocytes (purity over 95%). Random forests was selected as supervised classification algorithm, using two strategies: simultaneous with 3 classes (T/NK, healthy and CLL B) and sequential (fisrt: T/NK vs B, second: healthy vs CLL B).

The results obtained on the discrimination between healthy and diseased cells show the true potential of Raman spectroscopy coupled with the supervised classification for the diagnosis of CLL. Future studies will focus on the prognosis of CLL.

Poster Presentation

Session III

ThP-P-IIIA: SERS and Applications

Time: Thursday, 18/Aug/2016: 5:00pm - 7:00pm  ·  Location: Exhibition Hall

Study on Template Effect of Hybrid Self-assembled Surface Monolayers via SERS Technique

Weidong Ruan1,2, Yujeong Park1, Sila Jin1, Chengbin Sun2, Tieli Zhou2,3, Bing Zhao2, Young Mee Jung1

1Department of Chemistry, and Institute for Molecular Science and Fusion Technology, Kangwon National University, Chunchon 24341, Korea; 2State Key Laboratory of Supramolecular Structure and Materials, Jilin University, Changchun 130012, China; 3College of Food Engineering and Landscape Architecture, Changchun University, Changchun 130012, China; ruanwd@jlu.edu.cn

Alkanethiol molecules are one of the most important building molecules which possess special properties on supramolecular self-assembly. They can form ordered structures spontaneously on the metal surfaces. Nowadays alkanethiol molecules are widely used as mimetic biological membranes. Most researchers are trying to explore the bio-applications of these monolayers, but the study on the supramolecular structures is relatively weak. Therefore, the supramolecular structures of self-assembled alkanethiols with hybrid molecules were studied in the present study. Surface-enhanced Raman scattering (SERS) technique was employed to investigate the target supramolecular structures. The hybrid monolayers were composed by monolayered hexanethiols (HTs) on silver (Ag) nanoparticles (NPs) with inlaid mercaptopyridine (MPY) molecules. From the SERS spectra, we found that the hybrid monolayer structures were HT monolayers adsorbed on the surfaces of Ag NPs and the hybrid molecules of MPY were on the membrane’s surfaces.


Estimation of adsorptive parameters of Malachite Green on Gold nano colloid: SERS and Fluorescence spectroscopy study

Sannak Dutta Roy, Joydeep Chowdhury

Jadavpur University, India; sannak300@gmail.com

Surface enhanced Raman scattering (SERS) is a versatile spectroscopic technique which has the sensitivity to detect the presence of molecule down to single molecular level. SERS can also provide useful information concerning the interaction mechanism of the adsorbed molecules in the vicinity of metal nano structure[1,2]. In our work we have synthesized spherical gold nanocolloids (AuNC) of particle size 32 nm by Fren’s method and observed normal Raman (NR) spectra of Malachite Green (MG), and SERS spectra at different concentrations of the adsorbate. The adsorptive parameters of the probe molecule adsorbed on as prepared gold nanocolloid has been estimated from the Langmuir type adsorption isotherm plot

Further, vibrational analysis of MG, ion sensing property of the SERS spectra is in progress in our laboratory.


No direct detection of DNA with silver capping nanoparticles using Raman spectroscopy due to the effect of plasmon located

Ricardo Eulises Báez Cruz1,2,3, Maria Fernanda Vargas Charry2, Manuel Melendrez Castro3, Carlos Vargas Hernandez2

1Department of Physics ,University of Concepcion, Chile; 2Optical Properties Laboratory Materials (POM), National University of Colombia campus Manizales; 3Advanced Nanocomposites Research Group (GINA), Hybrid Materials Laboratoy (HML), Department of Materials Engineering (DIMAT), University of Concepcion, 270 Edmundo Larenas, Box 160-C, Concepcion 4070409, Chile; rebaezc@unal.edu.co

The enhanced signal of DNA is reported owing to its no direct interaction with silver capping nanoparticles (Ag-NPs), which synthesized by the microwave assisted route. These nanoparticles were combined with DNA extracted from pig spleen. DNA/Ag-NPs system was analyzed through Raman spectroscopy to characterize them vibrationally and check if there is any SERS effect. The frequency of 986 cm-1 was associated with doubling bond C5H of Cytosine, this vibration had an 8% enhanced over the Thymine, with a 12% enhanced in intensity wagged a vibration of Methylene CH2 is active in 1169cm-1. All these possible arise could be due to Ag-NPs plasmon effect interacting with DNA, although the particles have a capping of PEG coming from the reaction process. SERS effect with DNA was evidenced, these routes characterization to open the possibilities of detecting DNA noninvasively, potentiate diagnostic methods with future biomedical applications.


Self-assembly of Au nanocolloids in the organised Langmuir- Blodgett Film of PMMA: Template driven SERS active substrate

SOMSUBHRA SAHA1, Manash Ghosh2, Joydeep Chowdhury3

1Department of Physics, Jadavpur University, 188, Raja S. C. Mallick Road, Kolkata, West Bengal 700032, India; 2Department of Spectroscopy, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India.; 3Department of Physics, Jadavpur University, 188, Raja S. C. Mallick Road, Kolkata, West Bengal 700032, India; somsubhrasaha86@gmail.com

SERS active substrate containing gold (Au) nanocolloids entrapped in the Langmuir- Blodgett (LB) film matrix of polymethyl methacrylate (PMMA) has been reported. The SERS efficacy of the as prepared substrate has been tested with trace concentrations of 4-Mercaptopyridine (4-MPy) molecules. Apparent Enhancement Factor ~1012 orders of magnitude estimated for the as prepared substrate. In order to investigate the detail surface morphology of the as prepared substrates the FESEM, AFM studies are in progress. The fractal dimension calculations and the 3D-FDTD simulation studies to understand the spatial distribution of electric fields around the self assembled Au nanoparticles are also in progress.


Concentration and pH Dependent SERS Study of 4, 5-Dicyanoimidazole Adsorbed on Colloidal Gold Nano Particles: FTIR, Raman, and SERS study aided by DFT calculation

Subhendu Chandra

Victoria Institution (College), India; subhenduchandra@yahoo.com

Surface enhanced Raman scattering (SERS) is a useful technique in surface physics and chemistry because of its high sensitivity and the potential in providing some useful information about the nature and orientation of adsorbed molecular species and the adsorbate metal interaction mechanism. It is emerging as a powerful spectroscopic tool for ultra sensitive chemical analysis down to the single molecule detection level. The Normal Raman (NR), Fourier transform infrared (FTIR) and surface enhanced Raman scattering (SERS) spectra adsorbed on nano colloidal gold surface of biologically and specially medically significant, 4,5-Dicyanoimidazole molecule has been investigated.


Dynamic Raman and Rayleigh Imaging of Single Suspended SERS Nanoparticles

Jörg Wissler, Martin Wehmeyer, Svetlana Brem, Sebastian Schlücker

University Duisburg-Essen, Germany; svetlana.brem@uni-due.de

Single “spherical” gold and silver nanoparticles (NPs) with molecules on their surface are not SERS-active.1 In contrast, dimers, trimers and clusters of noble metal NPs are detectable at the single-particle SERS level.2 The differentiation whether the Raman signal uniformly originates from all NPs or only from a few Raman-active ones is not straight-forward in suspension.


Developing a method to synthesize hybrid bimetallic Au-Ag – humic acid nanoparticles

Vinícius Marques da Silva1, Paola Corio1, Cintia Regina Petroni2, Gustavo Fernandes Souza Andrade3

1University of São Paulo, Brazil; 2Federal Institute of São Paulo, Brazil; 3Federal University of Juiz de Fora, Brazil; marquessilva.iqusp@gmail.com

Au-Ag systems are of particular interest for the preparation of SERS-active substrates: while Ag nanostructures typically provide larger enhancement in Raman intensities as compared to Au nanostructures, Au nanostructures are chemically more stable. The main objective of this work is to develop an optimized methodology to synthesize SERS-active hybrid bimetallic Au-Ag – humic acid nanoparticles to be applied to environmentally relevant species. Hybrid bimetallic Au-Ag – humic acid nanoparticles were prepared using sodium humic acid as a reducing and stabilizer agent. The synthesized nanoparticles may combine the qualities of the surface properties of Au and the optical enhancing properties of Ag with the significant affinity with various organic and inorganic pollutants of humic acid, that serves as an extraction phase associated with the SERS platform, favoring the interaction between organic molecules and metallic nanoparticles.


SERS and DFT Studies of 4’-Mercaptobiphenylnitrile Interfacial Complex on Copper, Silver and Gold Substrates

Dieric dos Santos de Abreu1, Marcia Laudelina Arruda Temperini2, Izaura Cirino Nogueira Diógenes1

1Universidade Federal do Ceará, Brazil; 2Universidade de São Paulo, Brazil; dieric@alu.ufc.br

In this work, SERS spectra of Cu, Ag and Au substrates modified with 4’-mercaptobiphenylnitrile (HS2PCN) were obtained without (ex situ) and with (in situ) applied potential aiming to study the dependence of the charge transfer mechanism on the interfacial metal-complex (MnL2; L = HS2PCN) nature as well as on the chemical identity of the substrate. The experimental assignments were supported by TD-DFT calculations. The relative intensities of the bands in the SERS spectra showed to be dependent on the applied potential, the wavelength of the exciting radiation and the substrate as well. One can conclude that for copper and silver substrates, the charge transfer transitions take place from the Fermi level to the LUMO orbitals of HS2PCN and for gold from HOMO orbitals of the adsorbed HS2PCN to the Fermi level, and the relative intensity of the X-sensitive band at 1085 cm-1 decreases on going from gold to copper.


Substrate fabrication for thin film investigations and molecule analysis via surface-enhanced Raman spectroscopy by means of metalorganic aerosol deposition

Sebastian Merten, Bernd Damaschke, Konrad Samwer, Vasily Moshnyaga

1. Physikalische Institut, Georg-August Universität Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen; smerten@gwdg.de

Usually Raman scattering has a poor efficiency limiting the practical application of Raman spectroscopy. Surface-enhanced Raman spectroscopy (SERS) helps to overcome this limit and opens further applications. We report on a possible new way to fabricate SERS active substrates. The gold nanoparticles were deposited by means of metalorganic aerosol deposition (MAD), a vaccum-free and solution-based deposition technique. We prepared a thin film of TiO2 (d = 12 nm) on Si (100) substrate and deposited an Au-layer on top of it. Before the Au-deposition only the overwhelming Si-background is seen in the Raman spectrum (P = 0.65 mW, λ = 633 nm). After Au-deposition a distinct Raman mode at 143 cm-1 appears which can be assigned to a Raman mode of the TiO2 thin film. Therefore, it is possible to investigate ultrathin films with this method. Futhermore, first attempts with Rhodamine 6G were made to show the capability for molecular specroscopy.


Interplay between hotspot and nanorods aggregate morphology by SERS and DDA simulation

Márcia Laudelina Arruda Temperini1, Klester dos Santos Souza1, Érico Teixeira Neto2, Diego Pereira dos Santos3

1Univeristy of Sao PAulo, Brazil; 2Laboratório Nacional de Nanotecnologia, CNPEM, Brazil; 3Universidade Estadual de Campinas, Brazil; mlatempe@iq.usp.br

In this communication, we explore the correlation between the Surface Enhanced Raman Spectroscopy (SERS) intensities of p aminothiophenol (pABT) and the morphologies of gold nanorods (AuNR) aggregates by SERS, electron transmission microscopy and DDA simulations. Based on these results a discussion will be presented about the role of the localized surface plasmon resonance LSPR-SERS dependence on the aggregates morphology. Our results would suggest that an efficient gold nanorod SERS substrate would be the one in which both morphologies are be privileged.


Catalytic and Surface-enhanced Raman Active Au@SiO2AuPd for oxidation reactions

Jean Claudio Santos Costa, Paola Corio, Liane Marcia Rossi

University of São Paulo, Brazil; paola@iq.usp.br

SERS combines chemical specificity, sensitivity and surface selectivity, being favorable for investigating molecular transformations at catalysts surface during plasmonic nanoparticle´s catalyzed reactions. In this work, we describe the synthesis, characterization and SERS investigation of catalytic activity of the hybrid system Au@SiO2-AuPd, which combines plasmonic (Au) and catalytic (AuPd) activity. The investigated reaction is the oxidation of cinnamyl alcohol, performed using a Fischer–Porter reactor. In a typical solventless reaction, the reactor was loaded with Au@SiO2AuPd and cinnamyl alcohol. In terms of reaction mechanism, SERS results suggest that cinnamaldehyde is formed directly via cinnamyl alcohol. The composition of the bulk solution determined by gas chromatography (GC) shows a distinct product distribution from SERS. This is expected since SERS measures the adsorbed products and GC measures the bulk composition. Comparison of both techniques is complementary, and relevant for picturing the molecular reaction mechanism. It is suggested that Au@SiO2AuPd prevents radicalar reactions.


Assessing the molecular capping chemical structure of silver nanoparticles and their surface self-assembling by Raman and Energy-dispersive X-ray spectroscopy

Victor Teixeira Noronha1, Francisco A. Sousa1, Francisco A. Cunha2, Pierre B. A. Fechine2, Enzo V. H. Agressott3, Alexandre Rocha Paschoal3, Amauri J. Paula1

1Solid-Biological Interface Group (SolBIN), Department of Physics, Federal University of Ceará - UFC, Fortaleza-CE, Brazil; 2Department of Analytical Chemistry and Physic-Chemistry, Federal University of Ceará - UFC, Fortaleza, Brazil; 3Department of Physics, Federal University of Ceará - UFC, Fortaleza-CE, Brazil; victor.tn99@gmail.com

Two types of biogenic protein capped-AgNPs and two types of synthetic were used in this work. Synthetic nanoparticles were produced from the reduction of Ag+ with glucose and stabilized with two different capping agents, sodium citrate and dodecyl sulfate. All types of nanoparticles were attached and self-organized as a coating and stabilize themselves in silicon substrates with flat surfaces. SERS effect was used to compare the chemical groups stabilizing the silver nanoparticles, and to reveal the chemical groups that interact with a solid surface when all AgNPs were self-assembled on the Si substrates. EDS mapping performed at large length scales was used for revealing the possible influence of the AgNPs physicochemical characteristics on the AgNPs coating features attained after their surface assembly on model silicon substrates. Raman spectroscopy showed differences in bands and relative intensities between biogenic and synthetic AgNPs, thus allowing the identification of the different types of capping.


Single-molecule surface-enhanced Raman scattering spectroscopy of porphyrins and light harvesting complexes

Sylwester Gawinkowski1, Richard Lane1, O. Planas2, Santi Nonell2, Maria Pszona3, Jacek Waluk3, Niek van Hulst1,4

1ICFO - The Institute of Photonic Sciences, Spain; 2Institut Quimic de Sarria, Universitat Ramon Llull; 3Institute of Physical Chemistry PAS; 4ICREA – Institució Catalana de Recerca i Estudis Avançats; Sylwester.Gawinkowski@icfo.es

The SERS technique reached a single molecule sensitivity nearly two decades ago [1,2]. Recently it was showed that also single molecule surface-enhanced coherent Raman spectra can be measured with femtosecond time resolution [3]. Further development in the field can provide tools for investigating the mechanism of chemical reactions going on the timescale of molecular vibrations on the single molecule level. Only a few biomolecules were detected on the single molecule level with the SERS technique. Due to large size of such molecules it is difficult for them to approach the very hotspot. Biomolecules are also more sensitive to extremal electromagnetic fields in the hotspot. These problems can be solved by proper design of the nanoantenna as well as the application of coherent Raman spectroscopies. Comparison of the Raman and SERS spectra of LH2, bacteriochlorophil and model porphyrins [5,6] located nearby and far away from the optical antenna will be presented.


Gold Nanoparticle Aggregations on Recyclable Hierarchical Nanotrays for Surface-enhanced Raman Spectroscopy with Macroscale Uniformity

Kaiyu Wu, Tao Li, Michael Stenbæk Schmidt, Zhongli Wang, Tomas Rindzevicius, Sokol Ndoni, Anja Boisen

Department of Micro- and nanotechnology, Technical University of Denmark, Denmark; kaiwu@nanotech.dtu.dk

We present a novel nanofabrication process to manufacture recyclable hierarchical silicon/alumina nanotrays (SANTs). Highly ordered arrays of SANTs were made by IC-compatible processes over entire wafers. Gold nanoparticles were pinned to SANTs, enabling the structures to be used for surface-enhanced Raman spectroscopy (SERS). The gold nanoparticles further detached themselves from SANTs upon drying of analyte solvent, and subsequently formed aggregations with nanogaps, inside which the SERS hot spots and the analytes were simultaneously located. Such a substrate demonstrated a high average SERS enhancement factor of ~2 × 108, with a macroscale SERS uniformity of 6% CV across 40 mm (obtained from 41 evenly distributed data points). Furthermore, after SERS analyses, the SANTs were recycled by complete removal of gold via wet etching. The reused substrate exhibited very low SERS backgrounds as well as excellent SERS reproducibility, in comparison to those obtained on a new substrate.


Research on the Detection of Intangible Cultural Heritage Liang-cloth with Handheld SERS

Yan Wang1, Yan Gong1, Qi Pang2, Changyong Shi3, Xiaoyun Li4, Bei Shen5

1Beijing Institute Of Fashion Technology, China, People's Republic of; 2School of art and design, Beijing Institute Of Fashion Technology, Beijing 100029; 3Foundation department, Beijing Institute Of Fashion Technology, Beijing 100029; 4Metrohm China Limited, Beijing 100005; 5Guangxi Arts and Crafts Institute, Guangxi, 530012; 2205206742@qq.com

Insitu identification of textile intangible cultural heritage is the basic assurance and efficient method for art researches samples’ authenticity. Liang cloth, one kind of nature indigo dyed Fabric from Dong minority, which includes unique traditional ethnic handcrafts, belongs to intangible cultural heritage. In recent years, due to effects of industrialization, non-natural indigo machined fake Liang cloth haven been being used which causes the fact that art workers have to put a lot of energy into collecting samples. The development of Surface-Enhanced Raman Scattering (SERS) and Handheld Raman technique created a new application for insitu identification of textile. This article points out the Handheld SERS application direction of textile intangible cultural heritage by preparing Au/Ag mixed sol and combining with latest Handheld Raman technique


Silver coated gold nanoparticle assembled in Langmuir- Blodgett Film of DPPC: A sensitive SERS substrate

Somsubhra Saha1, Manash Ghosh2, Joydeep Chowdhury3

1Department of Physics, Jadavpur University, India; 2Dept.of Spectroscopy, Indian Association for the Cultivation of Science, India; 3Department of Physics, Jadavpur University, India; spmkg@iacs.res.in

Self-assembly of metal nanoparticles organized in the Langmuir Blodgett film of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) has been reported. We have shown that these self-assembled silver coated gold (Au@Ag) nanoparticles organized over DPPC monolayer serve as an efficient SERS active substrate. R6G is used as Raman probe molecule and the limit of detection for trace concentration of this material has been achieved upto 1.0x10-20 M.


Influence of nanocluster geometry on the local field strengths in the junction hot-sites and SERS

Li-Lin Tay, John Hulse, Jeff Fraser

National Research Council, Canada; lilin.tay@nrc-cnrc.gc.ca

Studies have shown the intricate dependency of LSPR on the geometrical arrangement of nanoparticle structures but few have the relative electric field strength at the various electromagnetic hot-sites. Here, we investigate electric field at the junction hot sites in nanoparticle aggregates both by spectroscopic measurement and electromagnetic calculations. Junction hot-sites in nanoaggregates are of paramount importance in inducing strong SERS activity. This makes SERS an ideal technique for probing these junction hot-sites. Since the enhancement response in SERS is proportional to the fourth power of the local electric field, the molecules situated at the hot-sites will easily dominate the Raman spectrum of
an adsorbate on NP aggregate. Observed variability of SERS strength between NP aggregates has often been interpreted as the irreproducibility of SERS. However, this variation in SERS strength can be due to the variability of
electromagnetic field strength at the hot-sites in the various nanoaggregates assemblies.


Polarization and Angular Characteristics of Molecules Adsorbed on Silver Nanorod Arrays: A Relationship between SER(R)S Intensities and Ellipsometric Parameters

Martin Šubr1, Martin Petr2, Ondřej Kylián2, Josef Štěpánek1, Marek Procházka1

1Charles University in Prague, Faculty of Mathematics and Physics, Institute of Physics, Czech Republic; 2Charles University in Prague, Faculty of Mathematics and Physics, Department of Macromolecular Physics, Czech Republic; subr.Martin@seznam.cz

Silver nanorod arrays prepared by oblique angle deposition represent a versatile, simple and inexpensive substrates for high sensitivity SERS applications. Their morphological properties suggest that they exhibit anisotropic response in terms of the SERS enhancement, the depolarization ratio as well as other optical (pseudo)parameters. In this contribution, polarization and angular characteristics of silver nanorod arrays are surveyed. Surface-enhanced (resonance) Raman scattering spectra of methylene blue (MB) adsorbed on the nanorod arrays are retrieved in the 90°-scattering geometry with varying tilting angle of the substrate θ, the azimuth angle φ and polarization of both the incident and the scattered radiation. The obtained data are related to ellipsometric parameters and interpreted in terms of the surface-selection rules. Information on the relative magnitudes of the Raman tensor elements is extracted and possible adsorptive stance of the analyte on the silver surface is inferred.


Use of single-drop microextraction technique to pre-concentration of para-mercaptobenzoic acid and its detection by SERS on goldnanoholes

Elias Barros Santos1, Jacson Weber Menezes2, Luis Fernando Ávila3, Alexandre Guimarães Brolo4

1Federal University of São Paulo; 2University of Pampa; 3School of Technology/University of Campinas; 4University of Victoria; santos.barros@unifesp.br

Surface-enhanced Raman scattering (SERS) has emerged in recent years owing to its potential to be employed as an extremely sensitive and fast technique for analytical applications. SERS is a highly sensitive spectroscopy with the ability for ultra-sensitive detection, and it has been widespread applied in chemistry, environmental analyses, and materials science. However, the success of SERS technique is dependent on the plasmonic activity of the nanostructures used as substrate. In this context, we are proposing in this work the use of the single-drop microextrcation technique as a pre-treatment step for molecules in low concentration before SERS anlysis. For this purpose, it was prepared aqueous solutions of para-mercaptobenzoic acid, used as Raman probe molecule. For the SERS analysis it was used goldnanoholes arrays substrate, which was prepared by interference lithography. All Raman measurements was carried out using a Jobin-Yvon T64000 Raman spectrometer system, with a laser at 633 nm.


Tunable Plasmonic Nanodomes

Mehmet KAHRAMAN1, Aysun KORKMAZ1, Handan YUKSEL2, Ramazan SOLMAZ2, Humeyra CAGLAYAN3

1Gaziantep University, Turkey; 2Bingöl University, Turkey; 3Abdullah Gül Üniversity, Turkey; mskahraman46@gmail.com

SERS is a powerful technique used for characterization of molecules and structures. Since plasmonic properties of the nanomaterials is one of the most important factor influencing SERS activity, tunable plasmonic properties of SERS substrates are crucial in SERS studies. In this study, we demonstrate a novel approach for fabrication of gold and silver nanodomes (AuNDs and AgNDs). First, convective-assembly method is used for deposition of the latex particles on a glass slide. After, PDMS is poured on the latex thin film to obtain nanovoids. The obtained nanovoids on PDMS are used as template for the fabrication of AuNDs and AgNDs. The nanovoids are filled with the deposition of Au and Ag by electrochemical method to obtain metallic NDs. Structural properties of the NDs are characterized using SEM and AFM. Optical characterization of the nanostructures is performed using SERS. The calculation of optical properties of the NDs is made by FDTD.


Surface-Enhanced Raman Scattering on Au-Ag Alloy Nanodomes

Aysun KORKMAZ1, Handan YUKSEL2, Ramazan SOLMAZ2, Mehmet KAHRAMAN1

1Gaziantep University, Turkey; 2Bingöl University, Turkey; aysunkorkmaz00@gmail.com

Surface-enhanced Raman scattering (SERS) is an emerging analytical technique for characterization of biological and non-biological molecules and structures. Fabrication of tunable plasmonic nanostructures is the focal point for the design of novel SERS substrates due to their major contribution of electromagnetic enhancement to the SERS enhancement mechanism. Electromagnetic enhancement is directly related with surface plasmons generating on the nanostructures. Several advanced methods have been used to fabricate 3D nanostructures to control and manipulate the plasmonic properties (wavelength of the surface plasmons and magnitude of the electromagnetic field generated on the surface) in order to maximize the enhancement factor for SERS experiments. In this study, we demonstrate a novel approach for the fabrication of Au-Ag alloy nanodomes (Au-AgNDs). The results demonstrate that plasmonic properties of the NDs can be tuned by changing of metal concentration in the alloy NDs.


Surface Enhanced Raman Spectroscopy of Carbon Nanotubes

Igor Dolamic1, Thomas Buergi1, Rudolf Bieri2

1University of Geneva, Switzerland; 2Stat Peel AG; igor.dolamic@unige.ch

We present SERS of carbon nanotubes deposited on various types of filters. The SERS active substrate consists of a filter decorated by plasmonic gold nanoparticles. Citrate-stabilized gold nanoparticles were prepared by conventional Turkevich method and exhibit a surface plasmon resonance (SPR) at 525nm. First, carbon nanotubes were deposited on the filter from a solution and Raman scattering excited at 532 nm was measured. Afterwards, five aliquots of 15 ml of gold nanoparticles were deposited on top of the CNTs. After each step of gold nanoparticle deposition, the Raman signal was re-measured at the same position. The deposition of nanoparticles leads to enhanced signals. The signal is strongly increasing till the third deposition and levels off afterwards. After the 5th deposition step the peak is enhanced 100 times. This indicates the creation of hot spots able to enhance the Raman signal of CNTs significantly.


High Raman-to-fluorescence ratio using close–packed gap-filled silver nanostructures

Hossein Khadem, Najmeh Sadegh, Seyed Hassan Tavassoli

Shahid Beheshti University, Iran, Islamic Republic of; h_khadem@sbu.ac.ir

Close-packed gap-filled self-assembled monolayers of silver nanoparticles were produced to observe the Raman signals of rhodamine 6G. Two mechanisms contribute to detect the Raman signals of the fluorescent sample: surface enhanced Raman scattering (SERS) and nanomaterial surface energy transfer (NSET). Different surface coverage densities of silver nanoparticles and filling the interparticle space with probe molecules were prepared through variation of substrate immersion time in nanoparticle solution and drying the substrate, respectively. Examination the effects of these two factors on the plasmonic response and SERS efficiency of substrate revealed that in a gap-filled dense coverage near-field interactions dominate which remarkably increase the Raman-to-fluorescence ratio (RFR). To have a perfect dense coverage, the efficient immersion time of about 48 hours was obtained. Our results also show that drying the substrates caused further enhancement in RFR through filling inter-particle spaces with dye molecules and, accordingly, increase in NSET efficiency.



Ultrasensitive Molecular Sensor Using N-doped Graphene through Enhanced Raman Scattering

Simin Feng1, Maria Cristina dos Santos2, Bruno R. Carvalho1,3, Ruitao Lv4, Qing Li5, Kazunori Fujisawa1, Ana Laura Elías1, Yu Lei6, Nestor Perea-López1, Morinobu Endo7, Minghu Pan8, Marcos A. Pimenta3, Mauricio Terrones1,6,7

1Department of Physics and Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, PA 16802, USA; 2Instituto de Física, Universidade de São Paulo, São Paulo, SP, Brazil; 3Departamento de Física, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, 30123-970, Brazil; 4Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, P. R. China; 5Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou 215123, P. R. China; 6Department of Material Science and Engineering, The Pennsylvania State University, University Park, PA 16802, USA; 7Institute of Carbon Science and Technology, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan; 8School of Physics, Huazhong University of Science and Technology, Wuhan, Hubei 430074, P. R. China; brunorc@fisica.ufmg.br

We present a comprehensive study on the graphene-enhanced Raman scattering (GERS) effect of pristine graphene and nitrogen-doped graphene. By controlling the nitrogen doping, the Fermi level of graphene shifts, and if this shift aligns with the LUMO of a molecule, charge transfer is enhanced amplifying the molecule vibrational Raman modes. We confirmed these findings using different organic molecules: Rhodamine B, Crystal Violet, and Methylene Blue. The Raman signals were detected even for concentrations as low as 10-11 mol/L. Furthermore, we demonstrated that when using different laser excitations, it is possible to determine the gaps between the higher occupied and the lower unoccupied molecular orbitals (HOMO-LUMO) of different molecules. Our simulated Raman spectra of the molecules also suggest that the measured Raman shifts come from the dyes having an extra electron. This work clearly demonstrates that nitrogen-doped graphene has enormous potential when detecting low concentrations of molecules and could also effectively identify their HOMO-LUMO gaps.


SERS of MEH-PPV on silver and gold nanoparticles

Alvaro C. C. Barra, Beatriz R. Moraes, Nathalia S. Campos, Celly M. S. Izumi

Universidade Federal de Juiz de Fora, Brazil; celly.izumi@ufjf.edu.br

In this work, surface-enhanced Raman scattering (SERS) was employed to investigate the interaction of the conjugated polymer poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) with silver nanoprisms and gold nanostars. SERS spectra of MEH-PPV on gold nanostars and on silver nanoprisms display different spectral features indicating that MEH-PPV is structurally different close to the metal surface. SERS spectrum of MEH-PPV on gold nanostars shows a similar spectral profile of Raman spectrum of bulk MEH-PPV suggesting that there is minimal structural or chemical variation compared to the bulk polymer. On the other hand, the SERS spectrum of MEH-PPV on silver nanoprisms present some features different from bulk MEH-PPV indicating that MEH-PPV is adsorbed on silver nanoparticles in planar form with higher conjugated length compared to solid MEH-PPV.




ThP-P-IIIB: TERS and Applications

Time: Thursday, 18/Aug/2016: 5:00pm - 7:00pm  ·  Location: Exhibition Hall

Plasmon catalytic reactions at the nanoscale

Zhenglong Zhang, Volker Deckert

Leibniz Institute of Photonic Technology, Germany; volker.deckert@ipht-jena.de

With the help of plasmon-induced hot electrons, plasmonic catalysis was recently designed as a new exciting topic of heterogeneous catalytic reaction. The recent research indicates that plasmonic catalysis opens a route to concentrate and direct the energy of visible light to adsorbed molecules, hence, enhancing the rate of chemical reactions and offering a pathway to control reaction selectivity. We report on a new plasmon catalyzed cleavage reaction of pNTP at a single molecule level using a gold nanoparticle dimer to avoid the usual dimerization. TERS is a technique that provides molecular information at the noscale. A controlled dimerization of pNTP was monitored by AFM- and STM- TERS. Especially, the temperature of plasmonic catalysis can be btained by comparing stokes and anti-Stokes TERS directly at the site of interest. Our ewest experiments indicate that a chain-like polymerization initiated by plasmonic catalysis, can be in-situ driven at the nanoscale by using TERS.



AFM and TERS investigation of single virus particles

Isabell Götz1,2,3, Stephan Stöckel1,2,3, Evelyn Kämmer1,2,3, Thomas Bocklitz1,2,3, Konstanze Olschewski2,3, Dana Cialla-May1,2,3, Karina Weber1,2,3, Roland Zell4, Jürgen Popp1,2,3, Volker Deckert1,2,3

1Leibniz Institute of Photonic Technology Jena, Germany; 2Friedrich Schiller University Jena, Germany; 3InfectoGnostics Research Campus Jena, Germany; 4Jena University Hospital, Germany; volker.deckert@leibniz-ipht.de

By means of an AFM morphologic information even the ultrastructure of viral particles is obtainable without a cultivation of viruses and without an invasive alteration prior to the measurements. Thus, a combination of the morphological characteristics with spectroscopic information of the virions on a single particle level is possible by using the highly sensitive tip-enhanced Raman spectroscopy (TERS).

To practically demonstrate the dependence of the measured viral dimensions from the applied measuring technique, the exact same particles were probed by AFM and scanning electron microscopy (SEM) in a proof of principle.

In addition, AFM in combination with a classification model was used for an automatic discrimination of different viruses on a single particle level. Furthermore, TERS in combination with a chemometric analysis was applied to discriminate two virus species based on their spectra.




Nanoscale molecular orientation mapping at different temperature by Tip-Enhanced Raman Spectroscopy

Feng Shao1, Vivian Müller2, Benjamin T. King3, A. Dieter Schlüter2, Renato Zenobi1

1Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 3, CH-8093, Zurich, Switzerland; 2Department of Materials, Institute of Polymers, ETH Zurich, Vladimir-Prelog-Weg 5, CH-8093, Zurich, Switzerland; 3Department of Chemistry, University of Nevada, Reno, Nevada 89557-0216, United States; feng.shao@org.chem.ethz.ch

Molecular orientation plays an important role in molecular interactions. For generation of monolayer sheets with a homogenous orientation, the Langmuir-Blodgett (LB) technique is often used. It relies on orientation of amphiphilic molecules on an air/water interface. Numerous analytical methods have been proposed to meet the demand of accurate, reliable analysis of molecular orientation. However, none of them can simultaneously provide chemical fingerprints a