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Vaughan, John. "Photographic emulsions as SERS and SERRS surfaces". Thesis, University of Manchester, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.528271.
Pełny tekst źródłaGühlke, Marina. "Oberflächenverstärkte Hyper-Raman-Streuung (SEHRS) und oberflächenverstärkte Raman-Streuung (SERS) für analytische Anwendungen". Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2016. http://dx.doi.org/10.18452/17570.
Pełny tekst źródłaHyper-Raman scattering follows different symmetry selection rules than Raman scattering and, as a non-linear two-photon process, profits even more than Raman scattering from enhanced electromagnetic fields at the surface of plasmonic nanostructures. Surface-enhanced hyper-Raman scattering (SEHRS) could thus gain practical importance for spectroscopy. The combination of SEHRS and surface-enhanced Raman scattering (SERS) offers complementary structural information. Specifically, due to the localization of the enhancement to the close proximity of the nanostructures, this information can be utilized for the characterization of the interaction between molecules and metal surfaces. The aim of this work was to increase the understanding of the SEHRS effect and to assess its applicability to answer analytical questions. For that purpose, SEHRS experiments with excitation at 1064 nm and SERS experiments with excitation at the same wavelength, as well as with excitation at 532 nm - to detect SEHRS and SERS in the same spectral region - were conducted. As an example for non-resonant excitation, pH-dependent SEHRS and SERS spectra of para-mercaptobenzoic acid were examined. Based on these spectra, the interaction of different silver nanostructures with the molecules was characterized. beta-Carotene was used to study the influence of resonance enhancement by the excitation of a molecular electronic transition during SEHRS experiments. By the thiol-functionalization of carotene, a more intense interaction with the silver surface was achieved, which enables to obtain not only resonant SEHRS and SERS but also non-resonant SERS spectra of carotene. Hyperspectral SEHRS imaging in combination with microspectroscopy was demonstrated by analyzing the distribution of different dyes on structured plasmonic surfaces.
Speed, Jonathon. "Tailoring plasmonic substrates for SERS". Thesis, University of Southampton, 2011. https://eprints.soton.ac.uk/191315/.
Pełny tekst źródłaCecchini, Michael Peter. "Novel detection strategies using SERS". Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/11165.
Pełny tekst źródłaAhmad, Hossam [Verfasser], Heinz-Detlef [Akademischer Betreuer] Kronfeldt, Ulrike [Akademischer Betreuer] Woggon i Frank [Akademischer Betreuer] Hubenthal. "Gold substrates for SERS and SERS/SERDS measurements in seawater and Raman measurements through long optical fibers / Hossam Ahmad. Gutachter: Heinz-Detlef Kronfeldt ; Ulrike Woggon ; Frank Hubenthal". Berlin : Technische Universität Berlin, 2014. http://nbn-resolving.de/urn:nbn:de:kobv:83-opus4-48713.
Pełny tekst źródłaAhmad, Hossam [Verfasser], Heinz-Detlef Akademischer Betreuer] Kronfeldt, Ulrike [Akademischer Betreuer] [Woggon i Frank [Akademischer Betreuer] Hubenthal. "Gold substrates for SERS and SERS/SERDS measurements in seawater and Raman measurements through long optical fibers / Hossam Ahmad. Gutachter: Heinz-Detlef Kronfeldt ; Ulrike Woggon ; Frank Hubenthal". Berlin : Technische Universität Berlin, 2014. http://d-nb.info/1065669534/34.
Pełny tekst źródłaAhmad, Hossam Verfasser], Heinz-Detlef [Akademischer Betreuer] Kronfeldt, Ulrike [Akademischer Betreuer] [Woggon i Frank [Akademischer Betreuer] Hubenthal. "Gold substrates for SERS and SERS/SERDS measurements in seawater and Raman measurements through long optical fibers / Hossam Ahmad. Gutachter: Heinz-Detlef Kronfeldt ; Ulrike Woggon ; Frank Hubenthal". Berlin : Technische Universität Berlin, 2014. http://d-nb.info/1065669534/34.
Pełny tekst źródłaHan, Sungyub. "Optimization of Aggregating agents and SERS Substrates for SERS detection of Cotinine and trans 3'-hydroxycotinine". Scholar Commons, 2015. https://scholarcommons.usf.edu/etd/5499.
Pełny tekst źródłaPolwart, Ewan. "Development of SERS active fibre sensors". Thesis, University of Strathclyde, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249014.
Pełny tekst źródłaAxel, Bolz. "Papierbasierte Mikrofluidik-Systeme mit SERS-Detektion". Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/19765.
Pełny tekst źródłaRapid tests are widely used analytical methods for obtaining analytical information immediately on site. Surface enhanced Raman scattering (SERS) is a possible detection method for compounds in diluted samples. This thesis focuses mainly on three aspects: reproducibility of SERS signal intensity, interpretation of concentration curves and analysis of sample mixtures. The signal reproducibility was investigated using different deposition methods and measurement systems and the reproducibility of measurements was tested over longer periods of time. It was found that the most stable signal intensity was obtained using a combination of homogeneous deposition of a nanoparticle suspension on paper and a detection configuration that involves large diameters of both, the laser and the detection spot on the sample. It was shown with a laboratory setup, that comparatively stable measurements are possible with a relative standard deviation of approx. 20 % over a period of approx. 2.5 months. For the analysis and interpretation of the dependence of the SERS signal intensity on the concentration of the analyte, concentration series of different compounds were measured. The measurement data could be fitted with a Langmuir isotherm and explained with the Langmuir SERS model. For the measured thiol compounds an alternative option for quantification was found: the shift of certain SERS bands in the Raman spectrum as a function of analyte concentration. For the analysis of compound mixture in solution microfluidic paper-based analytical devices (µPADs) were used. It was observed that certain analytes which have a high affinity for the nanoparticles can be separated from the solution and thereby analyzed.
Yan, Bo. "Rationally designed substrates for SERS biosensing". Thesis, Boston University, 2013. https://hdl.handle.net/2144/12894.
Pełny tekst źródłaThe large electromagnetic field enhancement provided by nanostructured noble metal surfaces forms the foundation for a series of enabling optical analytical techniques, such as surface enhanced Raman spectroscopy (SERS), surface enhanced IR absorption spectroscopy (SEIRA), surface enhanced fluorescent microscopy (SEF), to name only a few. Critical sensing applications have, however, other substrate requirements than mere peak signal enhancement. The substrate needs to be reliable, provide reproducible signal enhancements, and be amenable to a combination with microfluidic chips or other integrated sensor platforms. These needs motivate the development of engineerable SERS substrate "chips" with defined near- and far-field responses. In this dissertation, two types of rationally designed SERS substrates - nanoparticle cluster arrays (NCAs) and SERS stamp - will be introduced and characterized. NCAs were fabricated through a newly developed template guided self-assembly fabrication approach, in which chemically synthesized nanoparticles are integrated into predefined patterns using a hybrid top-down/bottom-up approach. Since this method relies on chemically defined building blocks, it can overcome the resolution limit of conventional lithographical methods and facilitates higher structural complexity. NCAs sustain near-field interactions within individual clusters as well as between entire neighboring clusters and create a multi-scale cascaded E-field enhancement throughout the entire array. SERS stamps were generated using an oblique angle metal deposition on a lithographically defined piston. When mounted on a nanopositioning stage, the SERS stamps were enabled to contact biological surfaces with pristine nanostructured metal surfaces for a label-free spectroscopic characterization. The developed engineered substrates were applied and tested in critical sensing applications, including the ultratrace detection of explosive vapors, the rapid discrimination of bacterial pathogens, and the label-free monitoring of the enzymatic degradation of pericellular matrices of cancer cells.
Marotta, Nicole Ella. "Patterned nanoarray sers substrates for pathogen detection". Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37274.
Pełny tekst źródłaKibar, Seda. "Preparation And Characterization Of Silver Sers Nanotags". Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612818/index.pdf.
Pełny tekst źródłarvet Volkan December 2010, 88 pages Tags are materials used for labeling substances and so make possible the qualitative and quantitative analysis both in macroscopic and microscopic world. Nowadays, surface enhanced Raman spectroscopy became the favored one among the optical based-tag detection systems. Progress in surface enhanced Raman detection and imaging technologies depends on the availability of Raman labels with strong light scattering characteristics. In this study various SERS nanotags were prepared. An ideal SERS nanotag consists of three parts, core nanoparticle for enhancement, Raman active molecule for signature and a shell for protection and further functionalization. As a core material, silver nanoparticles were prepared using the chemical reduction method with sodium citrate as reductant. SERS enhancement provided by Ag particles prepared was examined. For colloidal stabilization and further surface modifications, silica with a controlled thickness was deposited on Ag nanoparticles. Three single-dye doped nanotags, Ag-BCB@SiO2 Ag-CFV@SiO2 and Ag-CV@SiO2 were prepared using positively charged dyes, brilliant cresyl blue (BCB), cresyl fast violet (CFV) and cresyl violet (CV). The effects of silica thickness and dye concentration in the reaction medium were examined. Stability of prepared nanotags and repeatability of the method were investigated. Multi-dye doped nanotags were prepared using BCB and CFV solutions mixed at various concentration ratios. Resulting Raman spectra Ag-BCB-CFV@SiO2 nanotags successfully exhibited characteristic peaks of each dye with a good resolution. In addition, the molar ratio between dyes BCB and CFV was reflected on the related spectra. A linear correlation was observed between the molar ratio of the dyes and their Raman intensity ratio.
Mahajan, Sumeet. "Engineering substrates for SERS : Fundamentals and applications". Thesis, University of Southampton, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.533255.
Pełny tekst źródłaFarazkhorasani, Fatemeh. "Raman and SERS studies of filamentous fungi". Royal Society of Chemistry, 2012. http://hdl.handle.net/1993/23855.
Pełny tekst źródłaOctober 2014
Al-Maqbali, Laila. "MicroRNA detection using silver nanoparticles and SERS". Thesis, University of Strathclyde, 2018. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=29568.
Pełny tekst źródłaAuchinvole, Craig Alexander R. "SERS nanosensors for intracellular redox potential measurements". Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/9706.
Pełny tekst źródłaEliasson, Kasper. "Quantification using SERS on a colloidal substrate". Thesis, Uppsala universitet, Fasta tillståndets fysik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-443582.
Pełny tekst źródłaGao, Yumin. "Influences des dépôts métalliques sur l'effet SERS". Paris 6, 1986. http://www.theses.fr/1986PA066061.
Pełny tekst źródłaCruz, Sandra Maria Alves da. "Nanocomposites as probes for biodetection by SERS". Doctoral thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/14134.
Pełny tekst źródłaThe present work aimed to explore the potential of new nanocomposites based on carbon nanostructures and metal nanoparticles for the detection of biomolecules through surface enhanced Raman scattering (SERS). In a first step, polyvinyl alcohol composites were prepared incorporating silver nanoparticles by two different reduction procedures. At first without introduction of carbon nanostructures. These composites showed good results for the SERS identification of nucleic acids. Next, the synthesis and characterization of graphene oxide was studied to be used in the preparation of silver and gold nanocomposites. The reduction of this nanomaterial with different chemical agents was explored, since its reduction degree may be a determinant factor for the application envisaged (biomolecules interaction). The preparation of the nanocomposites with silver and gold was performed with different reducing agents. The SERS activity of these new nanocomposites was then explored in the presence of different analytes, varying the experimental conditions for Raman spectra acquisition. It was interesting to verify that the silver containing nanocomposites presented the particularity to intensify the graphene D and G bands. It is also important to highlight that a new eco-friendly reducing agent was tested for the synthesis of the graphene oxide composites, an Eucalyptus Globulus extract. Other variable introduced was the preparation of gold nanostars synthesized with hydroxylamine in the presence of graphene oxide, which allowed the preparation of a new nanocomposite with SERS potential. Fibrous membranes were also prepared by electrospinning with the aim to prepare SERS supports with adequate topography and porosity for the formation of nanoparticles agglomerates for the creation of the so-called hot-spots and also to allow the penetration of the analyte molecules. The polymers polyvinyl alcohol and polyacrylonitrile were selected for electrospinning. Using this technique, electrospun mantles with silver and gold nanoparticles and nanocomposites were prepared. Several variables were studied, such as the introduction of the nano-fillers during the electrospinning process, later deposition of the nano-fillers on the simple electrospun polymeric fibres and surface functionalization of the simple polymeric membranes to link the nano-fillers. At last, the potentialities of using carbon nanotubes forests, produced by chemical vapor deposition and coated with gold film by sputtering, as new SERS substrates were explored. It was found that the SERS detection of DNA bases and ADN itself is possible using these substrates.
O presente trabalho pretendeu explorar as potencialidades de nanocompósitos, baseados em nanoestruturas de carbono e nanopartículas metálicas, para a deteção de biomoléculas através da técnica de difusão de Raman intensificada por superfície (SERS, surface-enhanced Raman scattering). Primeiramente foram preparados nanocompositos de álcool polivinílico com nanopartículas de prata sintetizadas através de dois métodos, ainda sem a presença de nanoestruturas de carbono. Verificou-se que estas membranas apresentaram bons resultados na identificação de ácidos nucleicos por SERS. A síntese e caracterização do óxido de grafeno que serviu de base para a preparação dos nanocompósitos de prata e ouro foi objecto de estudo. A sua redução química com diferentes agentes redutores foi explorada, uma vez que o grau de redução deste nanomaterial pode ser um fator determinante para a aplicação pretendida (interação com biomoléculas). A preparação de nanocompósitos de óxido de grafeno com prata e ouro foi realizada com diferentes agentes redutores. A atividade de SERS destes novos nanocompósitos foi então explorada na presença de vários analitos, em diferentes condições de aquisição dos espectros de Raman, bem como em diferentes tipos de suporte. Verificou-se que os nanocompósitos preparados com prata apresentaram a particularidade de permitirem a intensificação dos sinais de Raman das bandas D e G do grafeno. É de salientar a introdução de um novo agente redutor amigo do ambiente para síntese de compósitos de grafeno com nanopartículas metálicas: o extrato de eucalipto. Outra variável introduzida foi a preparação de nanopartículas de ouro em forma de nanoestrelas sintetizadas com hidroxilamina na presença de óxido de grafeno, tendo-se obtido assim um novo nanocompósito com potencialidades em SERS. Com o objectivo de preparar suportes para SERS com uma topografia e porosidade adequadas à criação de locais privilegiados para a agregação de nanopartículas metálicas e para a penetração das moléculas do analito foram produzidas mantas por electrofiação. Para tal, selecionaram-se os polímeros álcool polivinílico e poliacrilonitrilo. Com esta técnica preparam-se igualmente nanocompósitos de ouro ou prata e grafeno. Estudaram-se algumas variáveis de síntese, tais como a introdução de nanopartículas e nanocompósitos in situ, (isto é, durante o processo de electrofiação), deposição posterior das nanopartículas e dos nanocompósitos nas fibras poliméricas (preparadas previamente) e funcionalização superficial das mantas com o objectivo de ligar os nanomateriais a posteriori. Por fim, foi também explorada a potencialidade em SERS de novas estruturas compostas por florestas de nanotubos de carbono com cobertura de ouro produzidas por deposição química de vapor. Verificou-se que a detecção de bases de ADN e o próprio ADN é possível usando estes materiais.
Hugall, James T. "On the nature of SERS from plasmonic nanostructures". Thesis, University of Cambridge, 2013. https://www.repository.cam.ac.uk/handle/1810/267496.
Pełny tekst źródłaKöllensperger, Peter Andreas. "Label-free detection of DNA hybridisation using SERS". Thesis, Imperial College London, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.441415.
Pełny tekst źródłaÁvila, Avilés Rodolfo Daniel. "Obtención de nanosistemas biogénicos para aplicaciones en SERS". Tesis de Licenciatura, Universidad Autónoma del Estado de México, 2018. http://hdl.handle.net/20.500.11799/95309.
Pełny tekst źródłaNanotechnology as a field of great relevance at present has focused its efforts in the controlled obtaining of nanosystems of different shape, size, dispersion and chemical composition, as well as its different applications; Furthermore, the field of nanobiotechnology investigates the use of a biological material to manufacture nanosystems, which can improve the biocompatibility of the nanomaterial, which generates widely dispersed systems in size and morphology. For this reason, in the present research, the synthesis and characterization of three different nanosystems are presented: obtaining of silver and gold nanoparticles using Anemopsis californica extract as a reducing and stabilizing agent; generation of nanocomposites of biosynthesized graphene oxide functionalized with silver and gold nanoparticles; and obtaining of hybrid nano/microstructures of silver and gold nanoparticles using pollen grains of Dimorphotheca ecklonis as a template. In addition to the synthesis and characterization of the nanosystems, its evaluation was carried out as substrates for surface enhanced Raman spectroscopy (SERS) effect, occupying methylene blue as the signal molecule. Gold and silver nanoparticles with A. californica extract were obtained, using different solvents in the preparation of the extract (water, methanol and isopropanol), which shows significant differences in morphology depending on the type of metal of the nanoparticles and dependent of the kind of solvent used, likewise considering only hemispheric nanoparticles, significant differences were found depending on the solvent occupied for the preparation of the extract. The second system, graphene oxide synthesis is obtained by graphite exfoliation in an aqueous/surfactant system supported by A. californica extract, which adds functional groups to the 2D material surface, inducing the possibility of functionalization. Such material was functionalized by the biosynthesis of silver and gold nanoparticles, which adhered to the surface of the material, thus generating AgNPs/GO and AuNPs/GO nanocomposites. The third nanosystem evaluates the obtaining of hybrid nano/microstructures, in which pollen grains of Dimorphotheca ecklonis are used as a reducing and stabilizing agent in the synthesis of silver and gold nanoparticles, working at the same time as a biteplate for the adhesion of these, thus generating the hybrid nano/microstructures AgNPs/PG and AuNPs/PG. Finally, we report the evaluation of all the systems as substrates for the application in SERS, occupying methylene blue as a signal molecule. In the same way all the systems exhibited such property of application of the Raman signal, with special preference silver nanostructures, due to the predominant anisotropic morphology; the AuNPs/OG nanocomposites associated with the conglomeration of the particles and the properties of the template, and the nano/microstructures AgNPs/GP due to the agglomeration of the particles and the morphology of the template.
CONACYT
Olar, О. І., i V. І. Fediv. "SERS-technology as a direction of medical diagnostics". Thesis, БДМУ, 2017. http://dspace.bsmu.edu.ua:8080/xmlui/handle/123456789/17272.
Pełny tekst źródłaSharma, Narayan. "Solution Processable Surface Enhanced Raman Spectroscopy (SERS) Substrate". Bowling Green State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1434375587.
Pełny tekst źródłaCaria, Sara Isabel Augusto Fateixa. "Nanocomposites for SERS : synthesis, optical and analytical studies". Doctoral thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/11995.
Pełny tekst źródłaEsta tese descreve diversas estratégias preparativas assim como estudos de caracterização de nanocompósitos e outras nanoestruturas, para a análise em espectroscopia de Raman com intensificação por superfície (SERS). Em particular foi estudada a incorporação de nanopartículas (NPs) metálicas de Ag e Au em matrizes poliméricas visando avaliar o potencial destes materiais como novos substratos para SERS na deteção de moléculas. O primeiro capítulo consiste numa revisão bibliográfica, onde é destacado o desenvolvimento de novos substratos para SERS utilizando nomeadamente nanopartículas de Ag, Au e Cu. Numa primeira fase, esta secção apresenta uma breve descrição sobre as propriedades plasmónicas dos metais utilizados e alguns conceitos básicos de espectroscopia de difusão de Raman. Posteriormente, descreve-se em mais detalhe o efeito de SERS, revendo-se sobretudo a química de materiais descrita em trabalhos recentes tendo em conta a sua utilização como novas plataformas para análise química por SERS. O capítulo 2 descreve a síntese e caracterização de nanocompósitos de poli(acrilato de butilo) obtidos através de polimerização in situ por miniemulsão na presença de nanopartículas de Ag. Os nanocompósitos Ag/PtBA foram investigados como novos substratos de SERS visando o desenvolvimento de novas plataformas versáteis para deteção molecular. Estudos como o efeito da temperatura, pH e pressão foram investigados, visando a compreensão do efeito da matriz polimérica na difusão/adsorção do analito (ácido tiossalicílico) na superfície metálica. No capítulo 3, os nanocompósitos de Ag/PtBA descritos anteriormente foram investigados detalhadamente como substratos para bio-deteção em SERS, usando a adenina como analito modelo. Os nanocompósitos foram submetidos a vários tratamentos pré-analíticos para a bio-deteção da adenina. Foram realizadas experiências nos sistemas Ag/PtBA de modo a obter informação sobre o efeito do pH na deteção deste analito em soluções aquosas diluídas. Os nanocompósitos poliméricos obtidos apresentam a vantagem de poderem ser processados utilizando tecnologia disponível. Pelo que o estudo das suas propriedades térmicas é especialmente relevante. Assim, a influência da incorporação de NPs inorgânicas na temperatura de transição vítrea (Tg) do polímero PtBA foi investigada por meio de calorimetria diferencial de varrimento (DSC) e os resultados são apresentados no capítulo 4. Estes estudos descrevem efeitos na Tg do PtBA quando analisado em nanocompósitos obtidos por diferentes métodos (métodos ex situ e in situ), contendo nanopartículas metálicas com diferentes distribuições de tamanho e presentes em quantidade variável na matriz polimérica. Estes estudos possibilitaram relacionar a influência das NPs metálicas na mobilidade das cadeias poliméricas com as propriedades térmicas observadas. O capítulo 5 descreve a preparação e caracterização de materiais compósitos de base polimérica (PtBA) e NPs de Au com morfologia de bastonetes (NRs). Estes materiais foram investigados como substratos para SERS tendo originado um bom sinal de SERS na análise de 2-2’-ditiodipiridina. Investigouse igualmente o efeito da variação da morfologia das NPs metálicas (esferas e bastonetes), a razão de aspecto (R.A.) dos bastonetes e o tipo de matriz polimérica (PtBA e PnBA) no sinal de SERS. No capítulo 6 é descrita a utilização da técnica de SERS como método alternativo para a monitorização de alterações morfológicas de coloides de NRs de Au. Os NRs de Au foram recolhidos em diferentes fases de oxidação promovida pela presença de K2S2O8 e a sua sensibilidade como substratos de SERS foi avaliada utilizando o anião dietilditiocarbamato (DTC) como analito modelo. Os estudos foram realizados utilizando as linhas de excitação a 1064 nm e 633 nm. Este estudo demonstrou que a sensibilidade dos NRs de Au como substratos de SERS diminui à medida que a sua R.A. diminui devido à competitividade do CTAB (estabilizante) e o DTC pela superfície dos NRs. É de salientar que este processo é acompanhado por um diferente comportamento em termos de adsorção dos dois tautómeros do DTC à superfície do metal. O capítulo 7 introduz um novo tipo de compósitos para SERS, utilizando matrizes biopoliméricas. Assim, descreve-se a preparação e caracterização de nanocompósitos de carragenano e NPs de Ag. Nesta secção é avaliada a utilização destes materiais como novos substratos para a análise em SERS, utilizando a 2-2’-ditiodipiridina como molécula modelo. Descrevem-se estudos pioneiros que procuram relacionar a dependência do sinal de SERS com a força do gel. Para tal, realizou-se um estudo sistemático aos nanobiocompósitos usados como substratos de SERS em diferentes condições analíticas e investigaram-se as suas propriedades reológicas. No capitulo 8 é descrita a investigação de nanocompósitos de Ag/Gelatina como substratos para SERS, utilizando o anião dietilditiocarbamato como analito modelo. Realizaram-se várias experiências para correlacionar a variação da força do gel com o aumento do sinal de SERS bem como a diferente adsorção dos dois tautómeros do DTC à superfície do metal. Ao longo desta dissertação são apresentados metodologias distintas para a preparação e obtenção de nanocompósitos com base em polímeros (sintéticos ou naturais) e NPs metálicas (Ag e Au). Esta investigação não só permitiu a síntese e estudo de novos substratos para SERS mas também a compreensão do efeito matriz/NPs metálicas no sinal de SERS e na formação de “hot spots”. Este trabalho contribui para o enriquecimento na área da Nanociência e Nanotecnologia demonstrando a eficácia e reprodutibilidade de nanocompósitos com base em polímeros como novos substratos para SERS. Embora as propriedades óticas apresentadas por estes materiais serem aqui direcionadas para a deteção molecular pela técnica de SERS, estes materiais podem ser investigados em outras área tecnológicas.
This thesis describes several strategies as well as characterization of nanocomposites and other nanostructures, for analysis in surface enhanced Raman scattering (SERS). In particular, we studied the incorporation of metal nanoparticles (NPs) such as Ag and Au in polymer matrices to assess the potential of these materials as novel SERS substrates for the detection of molecules. The first chapter consists of a literature review, which emphasized the development of new substrates for SERS using nanoparticles, including Ag, Au and Cu. Firstly; this section presents a brief description of the plasmonic properties of the metals used and some basic concepts of Raman spectroscopy. Posteriorly, the SERS effect is described in more detail, mainly reviewing the materials chemistry described in recent studies in view of their use as new platforms for chemical analysis by SERS. Chapter 2 describes the synthesis and characterization of nanocomposites of poly(butylacrylate) obtained from in situ miniemulsion polymerization in the presence of Ag nanoparticles. Nanocomposites Ag/PtBA were investigated as novel SERS substrates for the development of new versatile platforms for molecular detection. Several studies such as the effect of temperature, pH and pressure were investigated in order to understand the effect of the polymer matrix on the diffusion and adsorption of the analyte (thiosalicylic acid) on the metal surface. In chapter 3, the nanocomposite Ag/PtBA described in Chapter 2 has been investigated in more detail as potential substrates for bio-detection in SERS. These substrates were exposed to various pre-treatment methods for the detection of adenine, a base deoxyribonucleic acid (DNA). A series of experiments were carried out in the Ag/PtBA systems in order to obtain information on the effect of pH variation in the detection of the analyte in dilute aqueous solutions. The obtained polymer nanocomposites have the advantage that they can be processed, using available technology. Thus, the study of their thermal properties is especially relevant. The influence of the incorporation of inorganic NPs in the glass transition temperature (Tg) of the polymer PtBA was investigated by differential scanning calorimetry (DSC) and the results are presented in Chapter 4. These studies describe the effect on the Tg of the PtBA when nanocomposites prepared by different methods (methods in situ and ex situ), containing metal nanoparticles with different size distributions and variable amounts in the polymer matrix are analysed. These studies correlate the influence of the metal NPs in the mobility of the polymer chains with the thermal properties observed. Chapter 5 describes the preparation and characterization of polymer-based composite materials (PtBA) and Au NPs with rod morphology (NRs). These materials were investigated as substrates for SERS, lending to a good SERS signal for 2-2'-dithiodipyridine. The effect of the morphology of the metallic NPs (rods and spheres), the aspect ratio (A.R.) of the rods and the type of polymeric matrix (PtBA and PnBA) on the SERS signal was also investigated. Chapter 6 describes the use of the SERS technique as an alternative method to monitor morphological changes in colloidal Au NRs. The Au NRs were collected at different stages of oxidation promoted by the presence of K2S2O8 and their sensitivity as SERS substrates was evaluated, using the anion diethyldithiocarbamate (DTC) as molecular probe. The studies were performed using excitation lines at 1064 nm and 633 nm. This study demonstrated that the sensitivity of the Au NRs as SERS substrates decreases as their A.R. decreases due to the competitiveness of CTAB (stabilizer) and DTC for the surface of NRs. It is noted that this process is accompanied by a different behaviour in terms of adsorption of the two tautomers of the DTC to the metal surface. Chapter 7 introduces a new type of composite SERS, using biopolymer matrices. Thus, it describes the preparation and characterization of nanocomposites based on carrageenan and Ag NPs. This section evaluates the use of these materials as novel substrates for SERS analysis, using 2-2'- dithiodipyridine as molecular probe. Pioneering studies correlating the dependence of the SERS signal with the gel strength is describe in more detail. Thus, systematic studies were performed on these nanobiocomposites used as SERS substrates in different analytical conditions and their rheological properties investigated. Chapter 8 described the investigation of Ag/gelatine nanocomposites as substrates for SERS, using the diethyldithiocarbamate anion as model analyte. Several experiments were carried out to correlate the variation of the gel strength with the increase of the SERS signal as well as adsorption of the two different tautomers of the DTC on the metal surface. Throughout this work are presented different methods for preparing and obtaining polymer-based nanocomposites (natural or synthetic) and metal NPs (Ag and Au). This research has not only enabled the synthesis and study of new substrates for SERS but also the understanding of matrix/metal NPs effects in the SERS signal and the formation of "hot spots". This work contributes to the enrichment in the area of Nanoscience and Nanotechnology, demonstrating the effectiveness and reproducibility of these polymer-based nanocomposites as new SERS substrates. Although the optical properties of these materials presented here are focussed on the molecular detection by SERS, these materials can be investigated in other technological area.
Simpson, Jonathan Robert Henry. "SERS-based nanoparticle biodetection using carbohydrate-lectin interactions". Thesis, University of Strathclyde, 2016. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=27026.
Pełny tekst źródłaSers, christine [Verfasser]. "Zielgene der RAS-Onkoprotein-abhängigen Signaltransduktion / christine Sers". Berlin : Humboldt-Universität zu Berlin, 2003. http://d-nb.info/1207637793/34.
Pełny tekst źródłaPereira, Anderson de Jesus. "Substratos vítreos com nanoestruturas metálicas para aplicações SERS". Universidade Federal de Viçosa, 2016. http://www.locus.ufv.br/handle/123456789/9872.
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Filmes finos metálicos nanoestruturados têm despertado considerável interesse devido à sua ca- pacidade de produzir Ressonância de Plasmons de Superfície (SPR), tornando-os versáteis para aplicação em espectroscopia Raman Intensificada por Superfície (SERS). Os metais usados, geralmente, são prata, ouro, cobre e níquel uma vez que a SPR desses metais estão localizados na região do visível. Neste trabalho, foi sintetizado e caracterizado um material híbrido, consti- tuído de nanopartículas de prata ou cobre autossuportadas sobre um substrato vítreo ativo à base de fosfato, para aplicação na espectroscopia SERS. Os precursores das nanoestruturas de prata ou cobre foram introduzidos como íon na composição do vidro (NaH 2 PO 4 -H 3 BO 3 -Al 2 O 3 ), na forma de AgNO 3 ou Cu 2 O, respectivamente. O tamanho e a forma das nanopartículas formadas possuem dependência com a temperatura e o tempo de tratamento térmico. Para verificação da sensibilidade dos substratos vítreos à umidade, medidas de absorção de água foram realizadas em função de várias concentrações de Al 2 O 3 . Os resultados mostraram que os substratos vítreos SERS ativos sintetizados com 15% de Al 2 O 3 não absorvem água e as nanopartículas não são removidas em solução. Usando a molécula cresil-violeta (CV) como molécula teste, foi pos- sível obter uma amplificação da ordem de 10 5 para os substratos vítreos borofosfatos dopado com íons Ag + . Os substratos dopados com íons de cobre foram avaliados quanto a atividade SERS, usando como molécula teste a rodamina B (RB). Estes substratos vítreos SERS ativos exibiram fatores de amplificação SERS (EF) de 10 7 e 10 8 , para as linhas de laser 514,5 nm e 632,8 nm, respectivamente, com uma excelente reprodutibilidade. A rugosidade da superfície dos substratos vítreos com as nanoestruturas de cobre aumenta com o tempo de tratamento tér- mico. A intensidade SERS apresenta a mesma tendência, atingindo um máximo de amplificação para a amostra tratada durante 20 minutos. Para o tratamento durante 30 minutos, nota-se uma diminuição na intensidade. Os processos cinéticos de difusão e adsorção, responsáveis pela formação de auto-arranjos de nanoestruturas de cobre (mounds) sobre superfície dos vidros borofosfatos, foram estudados usando o método Monte Carlo Cinético, implementando uma barreira cinética que aparece quando a partícula executa uma difusão intercamada no modelo Wolf-Villain (WV). Este modelo foi capaz de reproduzir o comportamento da rugosidade em função do tempo de tratamento térmico obtido experimentalmente, medido através do expoente de crescimento β e do expoente dinâmico z.
Nanostructured thin metallic films have attracted considerable interest due to its ability to pro- duce surface plasmon resonance (SPR), making them versatile for surface-enhanced Raman spectroscopy (SERS) applications. A variety of metals are commonly used include silver, gold, copper and nickel since the SPR these metals are located in the visible region. In this work, we were synthesized and characterized a hybrid material, composed of silver or copper nanopar- ticles auto supported onto phosphate based active glass substrate, which are suitable to SERS spectroscopy. The precursors of the silver or copper nanostructures were introduced as ions in the glass composition (NaH 2 PO 4 -H 3 BO 3 -Al 2 O 3 ) as AgNO 3 or Cu 2 O, respectively. The size and shape of the formed nanoparticles have a dependence with the temperature and time of thermal treatment. For check the humidity sensitive of the vitreous substrates, water absorption mea- surements were performed as a function of several Al 2 O 3 concentrations. The results showed that the vitreous substrates SERS active synthesized with 15% Al 2 O 3 do not absorb water and the nanoparticles are not removed in water solution. Using the cresyl violet molecule (CV) in ethanol as the model molecule, was possible to obtain an SERS amplification of 10 5 for vitreous borophosphates substrates doped with silver ions. The substrates doped with copper ions were evaluated for SERS activity, using the rhodamine B (RB) as the model molecule. These vitreous SERS active substrates exhibited SERS enhancement factor (EF) of 10 7 and 10 8 , for laser lines 514,5 nm and 632,8 nm, respectively, with an excellent reproducibility. The surface roughness of the vitreous substrates with copper nanostructures increases with the thermal treatment time. The SERS intensity shows the same tendency, reaching a maximum amplification to the sample treated for 20 minutes. For annealing during 30 minutes, a decrease in intensity is noted. The kinetic processes of diffusion and adsorption, responsible for the formation of copper nanos- tructures self-arrangements (mounds) on the surface of borophosphatos glasses, were studied using the Kinetic Monte Carlo method, implementing a kinetic barrier that appears when the particle performs an interlayer diffusion in Wolf-Villain model (WV). This model was capable of reproduce the behavior of the roughness as a function of the thermal treatment time obtained experimentally, measured by growth exponent β and dynamic exponent z.
Ray, Bryan Hubert. "SERS analysis of biological analytes using an azo tether". Laramie, Wyo. : University of Wyoming, 2005. http://proquest.umi.com/pqdweb?did=1095427621&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
Pełny tekst źródłaCarella, Yvonne. "Development of SERS for the determination of environmental pollutants". Thesis, University of Strathclyde, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288745.
Pełny tekst źródłaHarper, Mhairi. "DNA diagnostic assays using Surface Enhanced Raman Scattering (SERS)". Thesis, University of Strathclyde, 2013. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=22401.
Pełny tekst źródłaMcAughtrie, Sarah. "2D and 3D optical imaging of SERS nanotags intracellularly". Thesis, University of Strathclyde, 2014. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=24532.
Pełny tekst źródłaZeng, Jianbo. "Gold Nanoshells: Synthesis and Applications to In Situ SERS". Miami University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=miami1362843561.
Pełny tekst źródłaCallahan, Jordan J. "Silver-embedded ZSM-5 Zeolites: a Reliable SERS Substrate". University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1342104242.
Pełny tekst źródłaZhou, Yan. "Synthesis, Characterization and Application of SERS-active Metal Nanoparticles". University of Cincinnati / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1458644099.
Pełny tekst źródłaJiang, Jing. "Quantitative measurement of intracellular redox potential using SERS nanosensors". Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/10482.
Pełny tekst źródłaBrulé, Thibault. "Spectral and temporal distribution of biomolecules by Dynamic SERS". Thesis, Dijon, 2014. http://www.theses.fr/2014DIJOS037/document.
Pełny tekst źródłaIn this thesis, the definition of SERS as a biosensor has been tested and a new approach developed for. Also, in terms of quantification, it has been shown that SERS can be an efficient tool. Concerning the selectivity, the spectral quality was improved. A low limit of detection associated to the statistical and dynamic approach allows a very good sensitivity (under the nanomolar). This approach also enables a high reproducibility in time of the sensor. Thus, as low as SERS does not well answer to the sensor capabilities in a classical approach, in our case the coupling between a non-functionalized GNPs substrate coupled with a microfluidic chip, all mounted on a confocal microscope for temporal dynamic studies statistically analyzed has contributed to define SERS as an efficient biosensor
Tijunelyte, Inga. "Development of SERS nanosensor for detection of water pollution". Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCD007/document.
Pełny tekst źródłaEnvironmental water pollution by organic compounds is in continues worldwide concern. Low molecular mass aromatic molecules consisting in benzene rings have received considerable attention due to a documented significant toxicity and carcinogenicity. Within the objectives of the European Water Framework Directives (2000/60/EC, 2006/118/EC and 2006/11/EC) aiming in water quality improvement, the development of analytical tools allowing in-situ accurate and sensitive detection is of primary importance and would be a meaningful innovation. With this regard, the main scope of this study was to design sensitive, reproducible, specific and reusable nanosensor for the detection of organic pollutants in environmental waters using Surface Enhanced Raman Spectroscopy (SERS).During this study the main attention was paid to the selection of suitable receptors and strategies for SERS nanosensor surface functionalisation in order to preconcentrate targeted pollutants. The application of antibodies and antigen binding fragments (F(ab)2) for surface decoration was found to be promising approach for highly selective nanosensor design. Another strategy exploited during this study was related with an application of cyclodextrins (CDs). Using Raman and SERS spectroscopies the size selective encapsulation of analytes was demonstrated. Finally, taking advantage of molecular identification in the complex environments offered by SERS technique, nanosensors providing non-specific molecular pre-concentration was considered. For this purpose several diazonium salts (DSs) were studied and applied to the surface functionalisation to create highly hydrophobic coating layer. The performance of such nanosensor was evaluated by detection of aromatic pollutants
PACCOTTI, NICCOLO'. "SERS active Ag/silicon based nanostructures for biosensing applications". Doctoral thesis, Politecnico di Torino, 2020. http://hdl.handle.net/11583/2839849.
Pełny tekst źródłaMühlig, Anna [Verfasser], Jürgen [Gutachter] Popp i Volker [Gutachter] Deckert. "Charakterisierung der Einflussfaktoren auf SERS-Spektren niedermolekularer Substanzen und medizinisch relevante Anwendungen des LOC-SERS-Systems / Anna Mühlig ; Gutachter: Jürgen Popp, Volker Deckert". Jena : Friedrich-Schiller-Universität Jena, 2016. http://d-nb.info/1177609118/34.
Pełny tekst źródłaGühlke, Marina [Verfasser], Janina [Gutachter] Kneipp i Inez [Gutachter] Weidinger. "Oberflächenverstärkte Hyper-Raman-Streuung (SEHRS) und oberflächenverstärkte Raman-Streuung (SERS) für analytische Anwendungen / Marina Gühlke. Gutachter: Janina Kneipp ; Inez Weidinger". Berlin : Mathematisch-Naturwissenschaftliche Fakultät, 2016. http://d-nb.info/1110941935/34.
Pełny tekst źródłaZamarion, Vitor de Moraes. "Funcionalização de nanopartículas plasmônicas para o desenvolvimento de sensores SERS". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-04092012-150535/.
Pełny tekst źródłaThe study of plasmonic gold nanoparticles under the conceptual point of view was the focus of this thesis, exploring mainly, the effects of molecular shell and the intensification of SERS spectra aiming at applications in chemical sensing. For the probe molecules, multifunctional species were selected, such as a 2,4,6-trimercapto- 1,3,5-triazine (TMT), 4,5-diamine-2,6-dimercaptopyrimidine (DadMcP or Dad) and mercaptoethylpyrazine (PZT) which present thiol groups able to anchor onto gold nanoparticles, leaving available sites for further interaction with substrates and metal complexes. It was observed that the molecular shell in Turkevich\'s method is very dependent on the synthesis condition, being possible to detect the intermediate product of citrate oxidation reaction in the nanoparticle surface, under controlled conditions, dramatically influencing the SERS behavior. A systematic study was conduct with the probe molecule 2,4,6-trimercapto-1,3,5-triazine anchored to gold nanoparticles either by changing the passivating layer (citrate), or for in situ synthesis with and without a reducing agent. These systems were investigated under different conditions as SERS sensors for metals. This study was extended to the probe molecule 4,5-diamine-2,6-dimercaptopyrimidine, exploiting the influence of time in the coordination of such species and also the effect of different kinds of eletrolytes in the aggregation process. Finally, it has been presented strong evidences for the occurence of photoinduced processes involving functionalized nanoparticles with emphasis on mercaptoethylpyrazine, whose bahavior has proved to be very unusual, generating photoaggregated films under UV light influence, with possible applications in photolithography.
Lamping, Sarah Louise. "Study of SERS for the detection of drugs of abuse". Thesis, University of Strathclyde, 2008. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21989.
Pełny tekst źródłaRobson, Anna. "SERS-active peptide nanoparticles for investigating protein allostery and bionanoassembly". Thesis, University of Strathclyde, 2012. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=18938.
Pełny tekst źródłaMunera, Caesar A. "SERS intensity correlations to LSPR on aggregated Au Ag systems". Thesis, San Jose State University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10255568.
Pełny tekst źródłaThe optimal surface enhanced Raman scattering (SERS) intensity was correlated to the localized surface plasmon resonance (LSPR) of individual and aggregated gold core/silver shell (Au@Ag) nanoparticles (NPs) in titrations involving the addition of both SERS label (e.g., rhodamine 6G, R6G) and the non-SERS active aggregant (chemical species that triggers the aggregation of NPs) potassium chloride (KCl). Titrating NP solutions with pure SERS label has often resulted in highly non-linear calibrations. In some cases, addition of non-SERS active aggregating agents such as KCl has also resulted in a large increase in SERS signals. An order of initial addition was followed in this report to find any advantage from the initial addition between the SERS label or the aggregant KCl. Interactions between Au@Ag solution and the SERS labels of R6G, 4 mercaptopyridine (MPY) and 4 mercaptobenzoic acid (MBA) were followed using spectrophotometric titrations. Evaluations of the role of aggregation in NP solutions were conducted through the micro-titrations using a quartz cuvette and in two separate stages: (1) a single amount of KCl was followed by increasing amounts of SERS label, and (2) a single amount of SERS label was followed by increasing amounts of KCl. The present reports allowed to conclude that the graphs of SERS intensity (λ EX = 785nm, corrected for solution absorption) versus aggregate absorptions (λAG = 830 nm) had a correlation between intense SERS and LSPR band extinctions.
Zamarion, Vitor de Moraes. "Estudos e aplicações de ressonância plasmônica superficial em nanosondas SERS". Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/46/46134/tde-28032008-092022/.
Pełny tekst źródłaSurface modification of gold nanoparticles with a molecule exhibiting several coordination points, allowed to elaborate an interesting concept for quantitative sensing conjugated with the SERS effect. In such systems it is important to know how the molecule binds to the surface, since, based on those informations one can elaborate sensors displaying high sensibility.. However, in dealing with the interaction of nanoparticles with light, the electrodynamic-quantum theories related to the interactions of the surface plasmons are not yet completely developed. In this way, in this t dissertation we made use of the current theories to understand the origin of the plasmons and of how they interact with the the nanoparticles. We have synthesized gold nanoparticles stabilized with 2,4,6-trimercapto-1,3,5-triazine and studied the ligand chemistry at the particles surface.. The influence of acid-base equilibria was studied based on the changes of the SERS spectra SERS with the pH, and interpreted in terms of the several equilibria of the species in solution. Finally, a new sensing concept, based on the observed changes in the SERS spectra in the presence of metal ions, was successfully demonstrated.
Salinas, Tavira César. "Evaluación del efecto SERS en azul de metileno y hemoglobina". Tesis de Licenciatura, Universidad Autónoma del Estado de México, 2020. http://hdl.handle.net/20.500.11799/109940.
Pełny tekst źródłaEn este trabajo se estudió el efecto del mejoramiento de la dispersión Raman por la superficie en soluciones diluidas de azul de metileno. Se usaron como sustratos nanoislas de oro obtenidas por evaporación térmica al alto vacío. El efecto mencionado, comúnmente conocido por sus siglas en inglés, efecto SERS (Surface-enhanced Raman Scattering), se estudió usando sustratos de oro depositados por evaporación térmica. El estudio se realizó en 5 etapas: En la primera etapa, se determinaron el disolvente, el volumen la solución y la temperatura del sustrato que permitieran que el analito, el azul de metileno, se pudiese colocar sobre un portaobjeto de manera uniforme. Esto es, evitando la formación de agregados de azul de metileno. Para ello se utilizó la espectroscopia Raman y microfotografías ópticas. En la segunda etapa, se demostró el efecto SERS, para ello se fue obteniendo el espectro Raman para diferentes diluciones. Se determinó que a la concentración de 10-5 molar el espectro Raman deja de observarse. Sin embargo al colocar la solución 10-5 molar sobre el sustrato SERS, la señal Raman se ve claramente. En la tercera etapa se determinó la dilución mínima detectable la cual fue de 10-20 Molar. En la cuarta etapa se estudió el efecto SERS como función de la longitud de onda y la mínima intensidad del haz láser. Observándose que para el azul de metileno sobre sustratos de oro, el efecto SERS va a depender en parte de la longitud de onda. Finalmente en la quinta etapa, se observó el efecto en una muestra biológica, la cual fue sangre, demostrándose que se puede detectar hemoglobina en concentraciones menores de 10-5 molar.
proyecto CONACyT No. A1-S-33899 proyecto PIIF-3-2018, PAPIIT-UNAM IN117116
Beffara, Flavien. "SERS biosensors based on special optical fibers for clinical diagnosis". Thesis, Limoges, 2021. http://www.theses.fr/2021LIMO0009.
Pełny tekst źródłaDespite important breakthroughs in biosensing, we are still in need of new sensors that would facilitate the early detection of severe diseases such as cancer. Classical tissue biopsy remains the gold standard in many cases. Although this approach has shown its potential, it remains invasive for the patients and the detection techniques are either tedious or lack the sensitivity to detect the disease at an early stage. Raman spectroscopy has demonstrated its interests for biosensing. Its ability to characterize the chemical nature, structure and the orientation of an analyte makes it an ideal candidate. The sharp Raman peaks of a molecule can be seen as a true fingerprint. Regrettably, Raman scattered signal is extremely weak. This limitation was overcome by surface enhanced Raman spectroscopy (SERS), since it drastically increases the Raman scattered signal while maintaining the sharp peak of the fingerprint spectrum of a molecule. Unfortunately, most of the current SERS substrates are 2D nano-roughened metal surfaces or colloidal nanoparticles, which lack the sensitivity and reliability in measurement with poor repeatability and reproducibility in the data. In the recent years, special optical fibers have been used as SERS platforms. They feature holes that run along their entire length. These holes allow for the analyte to be incorporated inside the fiber. Thus, such platform represents a promising alternative to planar substrates since the analyte and the excitation light can interact for longer length inside the fibers. In addition, optical fibers are very flexible, compact and allow for low-loss light guiding. Therefore, such fiber sensors exhibit the outstanding detection abilities of SERS, the advantages of optical fibers and improved sensitivity and reliability. In this manuscript, we aim to create a biosensing platform that could be routinely used in a clinical setting. For that, we propose to optimize the features of an already reported fiber topology. This allows us to increase its sensitivity while simultaneously improving its reliability and practicability. With this improved sensor, for the first time, we could detect the biomarker for ovarian cancer in clinical cyst fluids, which allowed us to differentiate the stage of the cancer. Subsequently, we propose a novel fiber topology, specifically designed to further increase the sensitivity of SERS-based fiber probes. This is achieved by increasing the surface of interaction compared to standard fiber sensors. For that, the core diameter is significantly increased and the amount of light that interacts with the analyte is precisely controlled. We envision that such functionalized fiber sensors could be incorporated inside a biopsy needle to create a two-in-one sensor for body fluid collection and readout that can eventually overcome the limitations associated with existing biopsy needle platforms, which demands for two-step sample collection and readout
Tymula, Sophie. "L'art du Roc-de-Sers (Charente) dans son contexte solutréen". Paris 1, 1999. http://www.theses.fr/1999PA010610.
Pełny tekst źródłaThis research study fits into the new-tought movement which aims at the paleolithic art works reinseration in their economic, social and cultural contexts. Trough the spatial-temporal recontextualization of the rock engraved art appliance of the solutrean establishment site of Roc-de-Sers (Charente), Formerly excavated, the author attempts to point out the stakes of that combined research approach, a basic one for the paleolithic art characterization. The latter is no more concerned with the general style-concept which confers to it a conspicuous unit in a large evolutive vision, neglecting the increasing regionalization process, but it incorporates the art into determinated cultures by technological-economical complexes systems. So estimated, the relations between art and society tempt to cancel the established partionings compound of endless symbolic approximations and evolutive assumed parallels, and reinforce the symbolic identity of each group. Relaying to the observations collected on the most tangible witnesses of this site establishment technological-economic unit, the technological, morphological and stylistic analysis of that exemplary rock art appliance engraved representations has led to dicern a stylistic conventions assemblage, which is proving to form a pertinent reference frame for the upper-solutrean art determination. On the light of these result it has been possible to reinsert the roc-de-sers rock art appliance in the French-Iberian solutrean contextual frame