Dissertations / Theses: 'Biosensors Surface plasmon resonance'

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Sommers, Daniel R. "Design and verification of a surface plasmon resonance biosensor." Available online, Georgia Institute of Technology, 2004, 2003. http://etd.gatech.edu/theses/available/etd-08172004-091020/unrestricted/sommers%5Fdaniel%5Fr%5F200505%5Fmast.pdf.

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Thesis (M. S.)--Bioengineering, Georgia Institute of Technology, 2004. William D. Hunt, Committee Chair ; Allen M. Orville, Committee Member ; Cheng Zhu, Committee Member ; Doug Armstrong, Committee Member ; Lawrence A. Bottomley, Committee Member. Includes bibliographical references.

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Jungar, Christina. "Affinity biosensors for carbohydrate-protein interactions using surface plasmon resonance /." Linköping : Univ, 2001. http://www.bibl.liu.se/liupubl/disp/disp2001/tek701s.pdf.

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Harris, Richard David. "Waveguide surface plasmon resonance biosensor." Thesis, University of Southampton, 1996. https://eprints.soton.ac.uk/398739/.

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This thesis reports the design and development of the first waveguide surface plasmon resonance (SPR) biosensor for pesticide analysis. The integrated optical format allows the fabrication of a compact sensor that may be connected to optical fibre; necessary steps towards a portable optical biosensor. A major advantage of the integrated optical approach is the possibility of fabricating multiple sensors on one substrate, and hence testing for multiple analytes in one basic assay. The SPR structure incorporates a metal film that may be employed as an electrode to study the electrochemical control of sensing reactions. The performance of such devices requires analysis of the waveguide modes supported by the metal-clad waveguide, of their excitation by an input waveguide and of the resultant power coupled into an output waveguide. For the first time a rigorous numerical waveguide model to study the power transmission of such general multilayer absorbing structures has been developed. The model allows the determination of the modulation in output power of the sensor due to the adsorption of a thin organic layer to the sensor surface, which in turn leads to a measure of sensitivity. Designs for practical, sensitive, waveguide SPR sensors for an aqueous environment, optimised for specific sensing films are reported. The fabrication of gold-coated, potassium ion-exchanged, waveguide SPR sensors in soda-lime and Pyrex glass is reported. Three types of experiment were performed to validate the waveguide model using these devices. The first involved measuring changes in the output power of the sensor as a function of gold film length. The second measured the SPR response of sensors as a function of gold film parameters. Third, the effect on the SPR response of binding a dual layer of biotin-avidin to the sensor surface was observed as a function of gold film thickness. Predictions of the waveguide model were compared to the experimental data. Optimisation of the sensor design through these experimental procedures is also described. The transformation of the basic waveguide SPR sensor into a specific biosensor for the triazine herbicides simazine and atrazine is reported. The assay procedure was based on anti-simazine and anti-atrazine IgG antibodies and their Fab fragments developed by co-workers at GEC Marconi Materials Technology Ltd., UK Chemical modification of the sensor surface was developed by co-workers at the University of Tubingen, Germany, to bind the antibodies to the sensor surface. Laboratory characterisation of the sensor as a simazine sensor was performed and is reported in this thesis. Extended validation identified a detection limit of 0.22µg/l for the herbicide simazine in the aqueous environment. The biosensor gave a significant correlation with HPLC measurements on natural water samples when the cross-reactivity of the sensor with other triazine herbicides was taken into account.

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Sommers, Daniel R. "Design and verification of a surface plasmon resonance biosensor." Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/6967.

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The Microelectronics Group has been researching sensors useful for detecting and quantifying events in biological molecular chemistry, for example, binding events. Our previous research has been based primarily on quartz resonators. This thesis describes the results of our initial research of Surface Plasmon Resonance (SPR) based technology. This study contains the design and implementation of a fully functional SPR biosensor with detailed disclosure of monolayer construction, digital hardware interfaces and software algorithms for process the SPR sensors output. An antibody monolayer was constructed on the biosensor surface with the goal of setting the strengths, weaknesses and limitation of measuring molecular events with SPR technology. We documented several characteristics of molecular chemistry that directly effect any measurements made using Surface Plasmon Resonance technology including pH, free ions, viscosity and temperature. Furthermore, the component used in our study introduced additional limitations due to wide variations amongst parts, the constraint of a liquid medium and the large surface area used for molecular interrogation. We have identified viable applications for this sensor by either eliminating or compensating for the factors that affect the measured results. This research has been published at the inaugural IEEE sensors conference and to our knowledge is the first time a biosensor has been constructed by attaching a sensor to a PDA and performing all signal processing, waveform analysis and display in the PDAs core processor.

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Cao, Jie. "Creation of novel gold-nanorod-based localized surface plasmon resonance biosensors." Thesis, City University London, 2013. http://openaccess.city.ac.uk/2990/.

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Starting with a comprehensive review of both surface plasmon resonance (SPR) based and localized surface plasmon resonance (LSPR) based sensors, this thesis reports the studies on the development of a novel sensitive gold nanorod (GNR) based label-free LSPR optical fibre biosensor, and the development of a novel robust method for effectively modifying the surface of cetyl-trimethyl ammonium bromide (CTAB) capped GNRs and their LSPR biosensing applications. A novel GNR-based LSPR optical fibre sensor was fabricated and evaluated in this work. The sensor probe was prepared by covalently immobilizing GNRs, synthesized using a seed-mediated growth method, on the decladed surface of a piece of multimode optical fibre. In order to operate the LSPR sensor as a reflective sensor, a silver mirror was also coated at one distal end of the sensor probe by a dip coating method. In the refractive index sensitivity test, it was found that the longitudinal plasmon band (LPB) of GNRs is highly sensitive to the refractive index change close to the GNRs surface, and the sensitivity of the LSPR optical fibre sensor increases with the increase of the aspect ratio of GNRs. The results showed that the GNR-based LSPR optical fibre sensors prepared in this work have linear and high refract index sensitivities. For sensors based on GNRs with aspect ratios of 2.6, 3.1, 3.7 and 4.3, their refractive index sensitivities were found to be 269, 401, 506 and 766 nm/RIU (RIU = refractive index unit), respectively, in the refractive index range from 1.34 to 1.41. In order to evaluate the biosensing performance, the GNR-based LSPR optical fibre sensor with aspect ratio of 4.1 and a 2 cm sensing length was further functionalized with human IgG to detect the specific target — anti-human IgG, and a detection limit of 1.6 nM was observed using a wavelength-based interrogation approach. In another study, in order to overcome the drawbacks of the CTAB-capped GNRs found in biosensing and biomedical applications, a simple yet robust pH-mediated method for effectively modifying the surface of CTAB-capped GNRs synthesized by the seed-mediated growth method was developed. This method allows the complete replacement of the CTAB molecules attached on the GNRs surface with the 11-mercaptoundecaonic acid (MUA) molecules to take place in a total aqueous environment by controlling the pH of the MUA aqueous solution, thus avoiding the irreversible aggregation of GNRs during the complex surface modification process observed in the previous reported methods. The success of the complete replacement of CTAB with MUA was confirmed by the surface elemental analysis using an X-ray photoelectron spectroscopy (XPS), and the MUA-modified GNRs created in this work demonstrated a high stability up to 4 months at least when stored in a buffer solution at pH 9 at 4°C. The MUA-modified GNRs with an aspect ratio of 3.9 were furthered developed as a solution-phase-based label-free LSPR biosensor by functionalizing the GNRs with human IgG. A detection limit as low as 0.4 nM for detecting anti-human IgG was achieved by this sensor. The achievements of this work are concluded and the directions of future work are also pointed out.

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Liu, Chang. "Localized Surface Plasmon Resonance Biosensors for Real-Time Biomolecular Binding Study." FIU Digital Commons, 2013. http://digitalcommons.fiu.edu/etd/837.

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Surface Plasmon Resonance (SPR) and localized surface plasmon resonance (LSPR) biosensors have brought a revolutionary change to in vitro study of biological and biochemical processes due to its ability to measure extremely small changes in surface refractive index (RI), binding equilibrium and kinetics. Strategies based on LSPR have been employed to enhance the sensitivity for a variety of applications, such as diagnosis of diseases, environmental analysis, food safety, and chemical threat detection. In LSPR spectroscopy, absorption and scattering of light are greatly enhanced at frequencies that excite the LSPR, resulting in a characteristic extinction spectrum that depends on the RI of the surrounding medium. Compositional and conformational change within the surrounding medium near the sensing surface could therefore be detected as shifts in the extinction spectrum. This dissertation specifically focuses on the development and evaluation of highly sensitive LSPR biosensors for in situ study of biomolecular binding process by incorporating nanotechnology. Compared to traditional methods for biomolecular binding studies, LSPR-based biosensors offer real-time, label free detection. First, we modified the gold sensing surface of LSPR-based biosensors using nanomaterials such as gold nanoparticles (AuNPs) and polymer to enhance surface absorption and sensitivity. The performance of this type of biosensors was evaluated on the application of small heavy metal molecule binding affinity study. This biosensor exhibited ~7 fold sensitivity enhancement and binding kinetics measurement capability comparing to traditional biosensors. Second, a miniaturized cell culture system was integrated into the LSPR-based biosensor system for the purpose of real-time biomarker signaling pathway studies and drug efficacy studies with living cells. To the best of our knowledge, this is the first LSPR-based sensing platform with the capability of living cell studies. We demonstrated the living cell measurement ability by studying the VEGF signaling pathway in living SKOV-3 cells. Results have shown that the VEGF secretion level from SKOV-3 cells is 0.0137 ± 0.0012 pg per cell. Moreover, we have demonstrated bevacizumab drug regulation to the VEGF signaling pathway using this biosensor. This sensing platform could potentially help studying biomolecular binding kinetics which elucidates the underlying mechanisms of biotransportation and drug delivery.

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Du, Yao. "Particle-modified surface plasmon resonance biosensor." Thesis, University of Cambridge, 2019. https://www.repository.cam.ac.uk/handle/1810/289388.

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Surface plasmon resonance (SPR) biosensors have attracted great attention in scientific research in the past three decades. Extensive studies on the immobilisation of biorecognition elements have been conducted in pursuit of higher sensitivity, but trialled formats have focussed on a thin layer modification next to the plasmon film, which usually requires in situ derivatization. This thesis investigates an 'off-chip' immobilisation strategy for SPR biosensing using silica particles and considers the implications of a particle-modified evanescent field on the signal amplitude and kinetics, for an exemplar affinity binding between immobilised IgG and its anti-IgG complement. Submicron silica particles were synthesized as carriers for the bio-recognition elements. They were then immobilised to form a sub-monolayer on the gold film of an SPR biosensor using two methods: thiolsilane coupling and physical adsorption aided by mechanical pressure. The bio-sensitivity towards an antigen/antibody interaction was lower than an SPR biosensor with an alkanethiolate SAM due to the difference in ligand capacity and position in the evanescent field. The binding kinetics of antigen/antibody pair was found to follow the Langmuir model closely in a continuous flow configuration but was heavily limited by the mass transport from the bulk to the sensor surface in a stop-flow configuration. A packed channel configuration was designed with larger gel particles as ligand carriers, packed on top of a gold film to create a column-modified SPR biosensor. This sensor has comparable bio-sensitivity to the previous sub-monolayer particle-modified systems, but the binding and dissociation of the analyte was heavily dependent on mass transport and binding equilibria across the column. A bi-directional diffusion mechanism was proposed based on a two-compartment mass transport model and the expanded model fitted well with the experimental data. The column-modified sensor was also studied by SPR imaging and analyte band formation was observed and analysed. Using the lateral resolution, a multiplexing particle column configuration was explored, and its potential in distinguishing a multicomponent analyte.

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Ou, Meigui. "Nanostructured gold surfaces as biosensors : surface-enhanced chemiluminescence and double detection by surface plasmon resonance and luminescence." Lyon, INSA, 2008. http://theses.insa-lyon.fr/publication/2008ISAL0057/these.pdf.

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This thesis is devoted to develop two biological detection systems based on nanostructured gold surfaces to detect the binding of streptavidin/biotin. In the first part, we have studied a multimodal detection system using local surface plasmon resonance of the gold substrate and the luminescence of labelling core-shell Gd2O3/SiOx nanoparticles, which profits from the plasmonic property of nanostructure gold. In a second part, we have focused in a surface-enhanced chemiluminescence system based on chemiluminescence of luminal/hydrogen peroxide (H2O2) enhanced by gold nanostructures in the vicinity, which benefits from the catalytic property of nanostructure gold. Several parameters influencing the chemiluminescence of luminal were investigated. Enhancing mechanism of luminal chemiluminescence was proved to be not related to Plasmon-assisted process but originates from catalytic properties of the metal induced by corrugation Cette thèse est consacré à développer deux systèmes pour la détection biologique à la base de la surface d’or pour détecter la liaison entre les molécules de biotine et de streptavidine. Premièrement, nous avons étudié un système de détection multimodal utilisant la résonance des plasmons de surface localisé sur substrats d’or et la luminescence de nanoparticules labellisées de coeur-écorce Gd2O3/SiOx, qui bénéficie de la propriété plasmonic d’or en nanostructure. Deuxièmement, nous avons focalisé sur un système qui se fonde sur le phénomène d’exaltation de chimiluminescence par la surface. La chimiluminescence de luminophore/ peroxyde d’hydrogène (H2O2) est exaltée par nanostructure d’or à proximité, qui bénéficie de la propriété catalytique de nanostructure d’or. Plusieurs paramètres ont été étudiés de manière systématique. Finalement, il est prouvée que le mécanisme de l’exaltation de chimiluminescence est originaire de la propriété catalytique du métal induit par la rugosité

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Sapsford, Kim Elizabeth. "The development of optical biosensors for nitrogen oxyanions using metalloproteins." Thesis, University of East Anglia, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327497.

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Wathen, Adam D. "An Exploration of Electron-Excited Surface Plasmon Resonance for Use In Biosensor Applications." Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5240.

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Electron-excited surface plasmon resonance (eSPR) is investigated for potential use in biosensors. Optical SPR sensors are commercially available at present and these sensors are extremely sensitive, but have the tendency to be relatively large, expensive, and ignore the potentials of microelectronic technology. By employing the use of various microelectronic and nanotechnology principles, the goal is to eventually design a device that exploits the eSPR phenomenon in order to make a sensor which is siginificantly smaller in size, more robust, and cheaper in cost.

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Wei, Dong. "Development of a surface plasmon resonance biosensor for the identification of Campylobacter jejuni." Auburn, Ala, 2006. http://repo.lib.auburn.edu/2006%20Summer/Theses/WEI_DONG_0.pdf.

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Canelle, Quentin. "Real Time Surface Plasmon Resonance Biosensors, a Powerful Technology to Assess Polyclonal Antibody Avidity." Doctoral thesis, Universite Libre de Bruxelles, 2015. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/216754.

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The present research focused on the development of a new methodology to assess the strength of the interaction between vaccine antigens and elicited polyclonal antibodies through SPR biosensors. Quantifying the binding strength of polyclonal antibodies is of first importance to evaluate the quality of the vaccine as well as to increase the scientific knowledge of immune protection mechanisms. To now the development of such tool has been complicated by the non-specific binding caused by high protein abundance in the blood and serum samples but also by the way of interpreting the data resulting from multi-interaction events measured at the same time. At first, we unsuccessfully tried to segregate the individual affinity contribution of each antibody population by measuring the signal as the sum of singular interactions. Differentiation of the singular contribution would have needed the fulfillment of the “additivity” hypothesis, meaning that each antibody bind identically alone or in mixture with other antibody. This hypothesis was not met and mathematical assessment by the sum of singular contribution led to fitting results that did not reflect the biological reality. It was therefore decided to switch the analysis method and to measure the end association binding level reached by the different samples injected at the same specific antibody content. The dissociation behavior was interpreted by the percentage of binding after long and fixed dissociation time. In a first application, we compared the antibodies elicited by two different commercially available vaccines and we showed that the binding interaction was not concentration dependent as, highly different levels were reached when injecting identical antibody concentration. No statistical significant difference was observed between both vaccines. Research firstly focused on the decrease of the non-specific binding and we found that ionic strength was a key parameter, increasing the buffer salt concentration reduced the non-specific binding without diminishing the binding strength. The sample composition was also a key parameter and purifying the IgG allowed to decrease dramatically the undesired binding events. A second application aimed at showing the equivalence between two different antigen constructions for two antibodies population. Even if identical antigen level immobilization is a challenge, the methodology is completely suitable to perform a 2-dimensional comparison (ligand and analyte). A last application was dedicated to the comparison between D and Q-pan Flu vaccines, and results showed that there was no statistical evidence of significant differences between both vaccines. End association level correlated well with haemagglutination inhibition assay at least when serum samples were not diluted at the same antibody content. This last application also showed that throughput may be extended to more than 50 samples per 80 hours Doctorat en Sciences agronomiques et ingénierie biologique info:eu-repo/semantics/nonPublished

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See, Erich Michael. "Modeling Plasmon Resonance for a Gold Nanoparticle Plasmon-Enhanced Cadmium Sulfide Biosensor." Miami University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=miami1249499557.

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Earp, Ronald Lee Jr. "Multiwavelength Surface Plasmon Resonance Sensor Designs for Chemical and Biochemical Detection." Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/30581.

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Surface plasmon resonance (SPR) sensors using multiwavelength light coupling are investigated to probe changes in refractive index that occur as a result of chemical or biochemical processes. Traditional SPR sensors have used angle modulation to facilitate detection at the sensor surface; however, the multiwavelength approach is novel and brings new functionality to SPR sensors. The multiwavelength sensors are constructed on both fiber optic and bulk waveguides such as prisms. A thin metal film is deposited on the waveguide surface to support the surface plasmon (SP) mode. The evanescent field produced by light propagating through the waveguide can be coupled into the surface plasmon mode thus attenuating the transmitted light. This coupling is dependent upon phase matching between the light wavevector and the surface plasmon wavevector. The wavevectors are directly related to the wavelength of light, thickness of analyte on the sensor surface and the refractive index of the analyte. As these parameters change, the light output from the sensor will be affected. Other thin films can be subsequently deposited on the metal to functionalize the sensor surface for a particular analyte of interest. A theoretical background and details of the sensor construction is given. The developed sensors are tested in a variety of application systems. Experimental results for refractive index sensing in bulk liquid applications is shown. Observed sensitivity approaches that of conventional SPR techniques. Alkyl-thiol monolayer systems are studied to investigate kinetics of formation and the thickness resolution of the sensor. A biochemical system is investigated to compare the sensors with other immunoassay techniques. Ionic self-assembled monolayer (ISAM) systems are investigated to probe structure and determine their usefulness as an immobilization layer for biochemical species. A mathematical model based on Fresnel reflection equations is developed to predict sensor response. This model can be used to selectively vary sensor parameters to optimize the response for a specific analyte system or to calculate system parameters based on experimental results. Results from the various experiments are compared with the model. Experimental results and interpretations are discussed along with future work and potential improvements. Classical SPR sensors are also discussed along with comparisons with the multiwavelength sensors. Future improvements to SPR sensors design are considered, as is the application of the technology to high-throughput drug screening for pharmaceuticals. Ph. D.

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Nygren, Babol Linnéa. "Folate binding protein in bovine milk : occurrence and properties studied with surface plasmon resonance /." Uppsala : Dept. of Food Science, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/2007102.pdf.

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Sanchez, Erik De Jesus. "Modeling of the Surface Plasmon Resonance (SPR) Effect for a Metal-Semiconductor (M-S) Junction at Elevated Temperatures." PDXScholar, 1993. https://pdxscholar.library.pdx.edu/open_access_etds/4624.

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The effect of temperature increase on the optical excitation of Surface Plasmon Resonance (SPR) at an Ag-Si metal-semiconductor (M-S) junction at a wavelength of 1 . 1 52 pm is investigated theoretically using computer modeling in Fortran. In order to accurately quantify the SPR, the temperature dependent optical constants for Ag and Si are obtained theoretically or semiempirically , using a Drude model for Ag and previous experimentally determined equations for Si (the behavior of the optical constants for crystalline Si and doped Si are found to have very little deviation between each other for our case). An improvement in the theoretical derivation for the optical constants of Ag is obtained, maintaining self-consistency. The optical constants are utilized to quantify the reflectance of an incident wave on an M-S junction, using Fresnel equations for a four layer system. The reflectivity of the M-S junction is indicative of the surface plasmon generation. There exists much industrial interest in increasing the amount of photocurrent generation in semiconductors for a given number of incident photons. This increase in photocurrent is often referred to as enhancing the quantum efficiency (Q). It has been previously shown by many groups that there can be an appreciable enhancement of Q due to the optical excitation of surface plasmons on a Schottky barrier junction (M-S junction), although all these previous studies were done at room temperature. Hence, the studies of temperature effect of SPR at the M-S junction could lead to interesting effects for the Q as well. In this thesis, we have studied qualitatively the effect of temperature increase on the optical excitation of SPR at an Ag-Si junction. From these results we have attempted to draw inference to the possibility of the enhancement of Q at elevated temperatures for such a diode junction.

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Nehru, Neha. "Reference Compensation for Localized Surface-Plasmon Resonance Sensors." UKnowledge, 2014. http://uknowledge.uky.edu/ece_etds/41.

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Noble metal nanoparticles supporting localized surface plasmon resonances (LSPR) have been extensively investigated for label free detection of various biological and chemical interactions. When compared to other optical sensing techniques, LSPR sensors offer label-free detection of biomolecular interactions in localized sensing volume solutions. However, these sensors also suffer from a major disadvantage – LSPR sensors remain highly susceptible to interference because they respond to both solution refractive index change and non-specific binding as well as specific binding of the target analyte. These interactions can severely compromise the measurement of the target analyte in a complex unknown media and hence limit the applicability and impact of the sensor. In spite of the extensive amount of work done in this field, there has been a clear absence of efforts to make LSPR sensors immune to interfering effects. The work presented in this document investigates, both experimentally and numerically, dual- and tri-mode LSPR sensors that utilize the multiple surface plasmon modes of gold nanostructures to distinguish target analyte from interfering bulk and non-specific binding effects. Finally, a series of biosensing experiments are performed to examine various regeneration assays for LSPR sensors built on indium tin oxide coated glass substrate.

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Bathae, Kumaresh Prasanth. "OPTIMIZATION OF A DUAL-MODE SURFACE PLASMON RESONANCE SENSOR." UKnowledge, 2007. http://uknowledge.uky.edu/gradschool_theses/424.

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Surface plasmon waves are TM polarized charge density waves that propagate at the interface of two media with real dielectric constants of opposite sign (i.e. liquid dielectric and certain metals). Surface plasmon resonance (SPR) sensors use these waves to detect refractive index changes adjacent to the metal layer. Refractive index changes arise from the binding of an analyte (e.g. a target molecule, protein, or bacterium) to the functionalized metal layer or from interfering effects such as changes in solution index. Standard, single channel SPR sensors cannot differentiate these two effects as their design allows only one mode to be coupled. This novel self-referencing technique employs two surface plasmon modes to simultaneously measure surface binding and solution refractive index. Dual surface plasmon modes are achieved by matching the refractive indices on either side of the metal film. The two modes generated - symmetric, long-range surface plasmon (LRSP) and anti-symmetric, short-range surface plasmon (SRSP) - have different field profiles and hence assist in differentiating solution refractive index changes from surface layer formation. Amorphous Teflon, with a refractive index close to water, is chosen as the buffer layer and gold is chosen as the metal layer. Magnesium fluoride, with a higher index than Teflon, is used as the buffer layer when using ethanol as the base solution. The sensor operation was optimized through simulations to yield higher sensitivity, lower reflectivity and resonances within the spectrometers range. Optimization results showed good performance over a wide range for Teflon, MgF2 and gold thicknesses which helped in the fabrication of the sensor. Demonstration of self-referencing operation was done through two different sets of experiments: (1) formation of an alkanethiol self-assembled monolayer on gold in the presence of ethanol and methanol solutions having different refractive indices and (2) streptavidin-biotin binding with solutions of different NaCl concentration and thus different refractive indices. In both these experiments, the resonance wavelengths were accurately predicted, reflectivity varied by 10-15% and sensitivity by 25% from that of the simulated values.

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Guo, Jing. "MULTI-MODE SELF-REFERENCING SURFACE PLASMON RESONANCE SENSORS." UKnowledge, 2013. http://uknowledge.uky.edu/ece_etds/13.

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Surface-plasmon-resonance (SPR) sensors are widely used in biological, chemical, medical, and environmental sensing. This dissertation describes the design and development of dual-mode, self-referencing SPR sensors supporting two surface-plasmon modes (long- and short-range) which can differentiate surface binding interactions from bulk index changes at a single sensing location. Dual-mode SPR sensors have been optimized for surface limit of detection (LOD). In a wavelength interrogated optical setup, both surface plasmons are simultaneously excited at the same location and incident angle but at different wavelengths. To improve the sensor performance, a new approach to dual-mode SPR sensing is presented that offers improved differentiation between surface and bulk effects. By using an angular interrogation, both surface plasmons are simultaneously excited at the same location and wavelength but at different angles. Angular interrogation offers at least a factor of 3.6 improvement in surface and bulk cross-sensitivity compared to wavelength-interrogated dual-mode SPR sensors. Multi-mode SPR sensors supporting at least three surface-plasmon modes can differentiate a target surface effect from interfering surface effects and bulk index changes. This dissertation describes a tri-mode SPR sensor which supports three surface plasmon resonance modes at one single sensing position, where each mode is excited at a different wavelength. The tri-mode SPR sensor can successfully differentiate specific binding from the non-specific binding and bulk index changes.

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Nordström, Helena. "Fragment Based Drug Discovery with Surface Plasmon Resonance Technology." Doctoral thesis, Uppsala universitet, Biokemi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-209136.

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Fragment based drug discovery (FBDD) has been applied to two protease drug targets, MMP-12 and HIV-1 protease. The primary screening and characterization of hit fragments were performed with surface plasmon resonance -technology. Further evaluation of the interaction was done by inhibition studies and in one case with X-ray crystallography. The focus of the two projects was different. Many MMP inhibitors contain a strong zinc chelating group, hydroxamate, interacting with the catalytic zinc atom. This strategy may be the cause for the low specificity of MMP inhibitors. Using FBDD we found a fragment with an unusual strong affinity for MMP-12. An inhibition assay confirmed that it was an inhibitor but indicated a stoichiometry of 2:1. Crystallography data revealed that an adduct of the fragment was bound in the active site, with interactions both with the catalytic zinc and the S1’ pocket. This may present a new scaffold for MMP-12 inhibitors. For HIV-1 protease the focus was on identifying inhibitors not sensitive to current resistance mutations. A fragment library for screening with SPR-technology was designed and used for screening against wild type enzyme and three variants with resistance mutations. Many of the hits were promiscuous but a number of fragments with possible allosteric inhibition mechanism were identified. The temperature dependency of the dissociation rate and reported resistance mutations was studied with thermodynamics. A good, but not perfect correlation was found between resistance and both the dissociation data and the free energy for dissociation compared to data from wild type enzyme. However, the type of mutation also influenced the results. The flap mutation G48V displayed thermodynamic profiles not completely correlating with resistance. It was found that dissociation rate and thermodynamics may complement each other when studying resistance, but only one of them may not be enough.

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Unser, Sarah A. "Improving the Sensitivity and Selectivity of Localized Surface Plasmon Resonance Biosensors Toward Novel Point-of-Care Diagnostics." University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1561997005551383.

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Akowuah, E. K. "Design and analysis of novel photonic crystal fibre and waveguide surface plasmon resonance biosensors operating in aqueous environments." Thesis, University of Kent, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.590071.

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Surface plasmon resonance (SPR) sensors provide high sensitivity without the use of molecular labels. Most commercial SPR biosensors are based on the simple, robust and highly sensitive traditional prism-coupled configuration. However, they are not amenable to miniaturization and integration. This has led to a growing interest in the development of robust, portable and highly sensitive SPR sensing devices capable of out of laboratory measurements. This thesis covers the modelling of these sensors, using the full vectorial finite element and the eigenmode expansion methods with the aim of optimising the proposed sensors for operation in aqueous environments. The thesis focuses on designs based on photonic crystal fibres and planar waveguides to achieve highly sensitive and compact platforms capable of multi analyte I channel operation. It is no longer feasible to optimise designs by simply fabricating and testing a large set of possible alternatives. This can be time consuming for complex devices such as SPR sensors. This requires computer models which can simulate the behaviour of the different designs in an accurate and speedy manner. This will make it possible to accurately predict device performance characteristics for different material and structural configurations, thereby affording designers the opportunity to experiment with different system configurations for optimal performance. In order to maintain modelling accuracy, all materials are modelled as dispersive and a full-wave analysis is undertaken. to account for the important frequency dependent effects. At every stage in this research, .,care was taken to bench-mark our results against the best available data, whether numerical or analytical whenever available, in order to validate our work. The effects of structural and material parameters on sensor performance metrics such as sensitivity are thoroughly investigated to arrive at optimised designs.

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Gongora, Renan. "Theoretical Tailoring of Perforated Thin Silver Films for Surface Plasmon Resonance Affinity." Honors in the Major Thesis, University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/1543.

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Metallic films, in conjunction with biochemical-targeted probes, are expected to provide early diagnosis, targeted therapy and non-invasive monitoring for epidemiology applications [1-4]. The resonance wavelength peaks, both plasmonic and Wood-Rayleigh Anomalies (WRAs), in the scattering spectra are affected by the metallic architecture. As of today, much research has been devoted to extinction efficiency in the plasmonic region. However, Wood Rayleigh Anomalies (WRAs) typically occur at wavelengths associated with the periodic distance of the structures. A significant number of papers have already focused on the plasmonic region of the visible spectrum, but a less explored area of research was presented here; the desired resonance wavelength region was 400-500nm, corresponding to the WRA for the silver film with perforated hole with a periodic distance of 400nm. Simulations obtained from the discrete dipole approximation (DDA) method, show sharp spectral bands (either high or low scattering efficiencies) in both wavelength regions of the visible spectrum simulated from Ag film with cylindrical hole arrays. In addition, surprising results were obtained in the parallel scattering spectra, where the electric field is contained in the XY plane, when the angle between the metallic surface and the incident light was adjusted to 14 degrees; a bathochromic shift was observed for the WRA peak suggesting a hybrid resonance mode. Metallic films have the potential to be used in instrumental techniques for use as sensors, i.e. surface plasmon resonance affinity biosensors, but are not limited to such instrumental techniques. Although the research here was aimed towards affinity biosensors, other sensory designs can benefit from the optimized Ag film motifs. The intent of the study was to elucidate metal film motifs, when incorporated into instrumental analysis, allowing the quantification of genetic material in the visible region. Any research group that routinely benefits from quantification of various analytes in solution matrices will also benefit from this study, as there are a bewildering number of instrumental sensory methods and setups available. B.S. Bachelors Sciences Chemistry

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Bang, Hyungseok. "INTEGRATED OPTICAL SPR (SURFACE PLASMON RESONANCE) SENSOR BASED ON OPTOELECTRONIC PLATFORM." Doctoral diss., University of Central Florida, 2008. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3289.

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Current major demands in SPR sensor development are system miniaturization and throughput improvement. Structuring an array of integrated optical SPR sensor heads on a semiconductor based optoelectronic platform could be a promising solution for those issues, since integrated optical waveguides have highly miniaturized dimension and the optoelectronic platform enables on-chip optical-to-electrical signal conversion. Utilizing a semiconductor based platform to achieve optoelectronic functionality poses requirements to the senor head; the sensor head needs to have reasonably small size while it should have reasonable sensitivity and fabrication tolerance. This research proposes a novel type of SPR sensor head and demonstrates a fabricated device with an array of integrated optical SPR sensor heads endowed with optoelectronic functionality. The novel integrated optical SPR sensor head relies on mode conversion efficiency for its operational principle. The beauty of this type of sensor head is it can produce clear contrast in SPR spectrum with a highly miniaturized and simple structure, in contrast to several-millimeter-scale conventional absorption type or interferometer type sensor heads. The integrated optical SPR sensor with optoelectronic functionality has been realized by structuring a dielectric waveguide based SPR sensor head on a photodetector-integrated semiconductor substrate. A large number of unit sensors have been fabricated on a substrate with a batch fabrication process, which promises a high throughput SPR sensor system or low-priced disposable sensors. Ph.D. Optics and Photonics Optics and Photonics Optics PhD

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Keathley, Phillip Donald. "DESIGN AND ANALYSIS OF NANO-GAP ENHANCED SURFACE PLASMON RESONANCE SENSORS." UKnowledge, 2009. http://uknowledge.uky.edu/gradschool_theses/643.

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Surface plasmon resonance (SPR) sensors are advantageous to other techniques of sensing chemical binding, offering quantitative, real-time, label-free results. Previous work has demonstrated the effectiveness of using dual-mode SPR sensors to differentiate between surface and background effects, making the sensors more robust to dynamic environments. This work demonstrates a technique that improves upon a previously optimized planar film dual-mode SPR sensor’s LOD by introducing a periodic array of subwavelength nano-gaps throughout the plasmon supporting material. First, general figures of merit for a sensor having an arbitrary number of modes are studied. Next, the mode effective index dispersion and magnetic field profiles of the two strongly bound modes found using a gap width of 20nm are analyzed. Qualitative analysis of the results demonstrates how such a design can enable better LODs in terms of each figure of merit. By optimizing a nano-gap enhanced sensor containing 20nm gaps, it is quantitatively demonstrated that the resulting modes improve upon almost every figure of merit, especially with respect to the orthogonality and magnitude of the sensitivity vectors, resulting in LODs approximately a factor of five less than the optimal planar design.

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Chang, Sehoon. "Organic/inorganic hybrid nanostructures for chemical plasmonic sensors." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/39545.

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The work presented in this dissertation suggests novel design of chemical plasmonic sensors which have been developed based on Localized Surface Plasmon Resonance (LSPR), and Surface-enhanced Raman scattering (SERS) phenomena. The goal of the study is to understand the SERS phenomena for 3D hybrid (organic/inorganic) templates and to design of the templates for trace-level detection of selected chemical analytes relevant to liquid explosives and hazardous chemicals. The key design criteria for the development of the SERS templates are utilizing selective polymeric nanocoatings within cylindrical nanopores for promoting selective adsorption of chemical analyte molecules, maximizing specific surface area, and optimizing concentration of hot spots with efficient light interaction inside nanochannels. The organic/inorganic hybrid templates are optimized through a comprehensive understanding of the LSPR properties of the gold nanoparticles, gold nanorods, interaction of light with highly porous alumina template, and the choice of physical and chemical attributes of the selective coating. Furthermore, novel method to assemble silver nanoparticles in 3D as the active SERS-active substrate has been demonstrated by uniform, in situ growth of silver nanoparticles from electroless deposited silver seeds excluding any adhesive polymer layer on template. This approach can be the optimal for SERS sensing applications because it is not necessary to separate the Raman bands of the polyelectrolyte binding layer from those of the desired analyte. The fabrication method is an efficient, simple and fast way to assemble nanoparticles into 3D nanostructures. Addressable Raman markers from silver nanowire crossbars with silver nanoparticles are also introduced and studied. Assembly of silver nanowire crossbar structure is achieved by simple, double-step capillary transfer lithography. The on/off SERS properties can be observed on silver nanowire crossbars with silver nanoparticles depending on the exact location and orientation of decorated silver nanoparticles nearby silver nanowire crossbars. As an alternative approach for the template-assisted nanostructure design, porous alumina membrane (PAM) can be utilized as a sacrificial template for the fabrication of the nanotube structure. The study seeks to investigate the design aspects of polymeric/inorganic hybrid nanotube structures with plasmonic properties, which can be dynamically tuned by external stimuli such as pH. This research suggests several different organic/inorganic nanostructure assemblies by various template-assisted techniques. The polymeric/inorganic hybrid nanostructures including SERS property, pH responsive characteristics, and large surface area will enable us to understand and design the novel chemical plasmonic sensors.

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Carvalho, Gomes Paula Alexandra de. "Surface plasmon resonance as a tool in the functional analysis of an immunodominant site in foot-and-mouth disease virus." Doctoral thesis, Universitat de Barcelona, 2000. http://hdl.handle.net/10803/2793.

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A fast and direct surface plasmon resonance (SPR) method for the kinetic analysis of the interactions between peptide antigens and immobilised monoclonal antibodies (mAb) has been established. Protocols have been developed to overcome the problems posed by the small size of the analytes (< 1600 Da). The interactions were well described by a simple 1:1 bimolecular interaction and the rate constants were self-consistent and reproducible. The key features for the accuracy of the kinetic constants measured were high buffer flow rates, medium antibody surface densities and high peptide concentrations. The method was applied to an extensive analysis of over 40 peptide analogues towards two distinct anti-FMDV antibodies, providing data in total agreement with previous competition ELISA experiments. Eleven linear 15-residue synthetic peptides, reproducing all possible combinations of the four replacements found in foot-and-mouth disease virus (FMDV) field isolate C-S30, were evaluated. The direct kinetic SPR analysis of the interactions between these peptides and three anti-site A mAbs suggested additivity in all combinations of the four relevant mutations, which was confirmed by parallel ELISA analysis. The four-point mutant peptide (A15S30) reproducing site A from the C-S30 strain was the least antigenic of the set, in disagreement with previously reported studies with the virus isolate. Increasing peptide size from 15 to 21 residues did not significantly improve antigenicity. Overnight incubation of A15S30 with mAb 4C4 in solution showed a marked increase in peptide antigenicity not observed for other peptide analogues, suggesting that conformational rearrangement could lead to a stable peptide-antibody complex. In fact, peptide cyclization clearly improved antigenicity, confirming an antigenic reversion in a multiply substituted peptide. Solution NMR studies of both linear and cyclic versions of the antigenic loop of FMDV C-S30 showed that structural features previously correlated with antigenicity were more pronounced in the cyclic peptide. Twenty-six synthetic peptides, corresponding to all possible combinations of five single-point antigenicity-enhancing replacements in the GH loop of FMDV C-S8c1, were also studied. SPR kinetic screening of these peptides was not possible due to problems mainly related to the high mAb affinities displayed by these synthetic antigens. Solution affinity SPR analysis was employed and affinities displayed were generally comparable to or even higher than those corresponding to the C-S8c1 reference peptide A15. The NMR characterisation of one of these multiple mutants in solution showed that it had a conformational behaviour quite similar to that of the native sequence A15 and the X-ray diffraction crystallographic analysis of the peptide - mAb 4C4 complex showed paratope - epitope interactions identical to all FMDV peptide - mAb complexes studied so far. Key residues for these interactions are those directly involved in epitope - paratope contacts (141Arg, 143Asp, 146His) as well as residues able to stabilise a particular peptide global folding. A quasi-cyclic conformation is held up by a hydrophobic cavity defined by residues 138, 144 and 147 and by other key intrapeptide hydrogen bonds, delineating an open turn at positions 141, 142 and 143 (corresponding to the Arg-Gly-Asp motif). Se diseñó un método rápido y sencillo para el análisis cinético por resonancia de plasmón superficial (RPS) de las interacciones entre antígenos peptídicos de bajo peso molecular (< 1600 Da) y anticuerpos monoclonales (AM) inmovilizados en la superficie de un chip sensor. Dichas interacciones se ajustaron a un modelo de interacción bimolecular 1:1 y las constantes cinéticas obtenidas resultaron fiables y reproducibles. Los parámetros clave para la calidad de las constantes cinéticas medidas fueron un flujo de tampón elevado, una densidad superficial de AM intermedia y una elevada concentración de péptido. El método se extendió a más de 40 análogos peptídicos frente a dos AM contra el virus de la fiebre aftosa (VFA), obteniéndose total correlación con datos anteriores de ELISA competitivo. Se sintetizaron once pentadecapéptidos con todas las combinaciones posibles de las cuatro mutaciones que caracterizan el bucle GH del aislado C-S30 del VFA respecto a la secuencia de referencia C-S8c1. Los resultados del análisis cinético directo, por RPS, de la antigenicidad de estos péptidos frente a tres AM sugirieron que dichas combinaciones eran aditivas, observación que fué confirmada por ELISA competitivo. Así, el tetramutante (A15S30) que mimetiza el bucle GH de C-S30 resultó ser el peor antígeno de la serie, en contraste con resultados anteriores con este aislado. Aumentando el tamaño del tetramutante de 15 a 21 aminoácidos no afectó significativamente su antigenicidad. En cambio, una incubación prolongada con el AM llevó a un aumento de reactividad no observado para otros análogos. Posiblemente una reordenación conformacional del péptido pudo conllevar a la formación de un complejo estable con el anticuerpo. Experimentos de RPS con un análogo cíclico del péptido A15S30 confirmaron una reversión en la antigenicidad del tetramutante inducible a través de restricciones conformacionales. Estudios de ambos péptidos, lineal y cíclico, por resonancia magnética nuclear (RMN) mostraron que características estructurales anteriormente correlacionadas con la antigenicidad eran más pronunciadas en el análogo cíclico. Se prepararon veintiseis péptidos con todas las posibles combinaciones de cinco sustituciones específicas en el bucle GH del VFA C-S8c1. Dichas sustituciones individuales habían sido objeto de estudios anteriores, obteniéndose una elevada antigenicidad para los correspondientes péptidos mutantes frente a AM anti-VFA. No se pudo sistematizar el análisis cinético por RPS de los nuevos mutantes multiples, debido a problemas tanto en la determinación de las constantes cinéticas de disociación, como en la regeneración de las superficies de AM. Se utilizó así la RPS para la determinación de la afinidad péptido - AM en solución, obteniéndose antigenicidades comparables o incluso superiores a las del péptido nativo A15 (VFA C-S8c1). Se estudió uno de los mutantes multiples (A15FPS) por RMN, observándose una conformación identica a la del péptido nativo. El estudio del complejo cristalino entre el péptido A15FPS y el AM 4C4 por difracción de RX mostró que las interacciones parátopo - epítopo eran similares a las observadas con el péptido nativo. Se concluyió que los residuos clave para el reconocimiento son tanto aquellos involucrados en contactos directos (141Arg, 143Asp, 146His) como aquellos que estabilizan el plegamiento adecuado del péptido. Así, una conformación casi cíclica es soportada por una cavidad hidrofóbica definida por los residuos 138, 144 y 147 y por puentes de hidrógeno intra-peptídicos clave, diseñándose un bucle abierto centrado en las posiciones 141, 142 and 143 (triplete Arg-Gly-Asp).

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Filion, Côté Sandrine. "Spectro-angular optical biosensor based on surface plasmon resonance operating in the visible spectrum." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=106424.

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Surface plasmon resonance (SPR) is one of the most widely used methods to implement biosensors because of its label-free and sensitive detection. Surface plasmon resonance allows the change in the refractive index of a sample to be measured accurately by the analysis of the light reflecting at a metal-dielectric interface. A way to increase the sensitivity of SPR biosensors was found in fabricating a spectro-angular SPR biosensor and using of a newly developed data processing method called the Double Projection Method. The objective of the work presented in this thesis is to improve further the detection limit of the spectro-angular biosensor by upgrading the cameras used for the data acquisition. Simulations have shown that the spatial resolution and the data precision have a significant impact on the accuracy of the refractive index change measurement. In this thesis, simulation results are presented to justify the modifications of the experimental system and to estimate the expected improvement in the detection limit of the spectro-angular biosensor by the use of higher spatial resolution and higher data precision cameras. The new design as well as the components purchased for the experimental set-up are detailed. La résonance plasmonique de surface (SPR) est une méthode très utilisée pour la réalisation de biocapteurs grâce à sa détection très sensible et sans marqueur. La résonance plasmonique de surface permet une mesure précise du changement de l'indice de réfraction d'un échantillon par l'analyse de la lumière reflétant sur l'interface entre un métal et un diélectrique. Il a été démontré que la sensibilité des biocapteurs SPR puisse être accrue par la fabrication d'un biocapteur SPR spectro-angulaire utilisant une nouvelle méthode de traitement des données appelée Double Projection Method (la méthode par double projection). L'objectif du travail présenté dans cette thèse est d'améliorer la limite de détection du biocapteur spectro-angulaire grâce à l'utilisation de caméras plus performantes pour la cueillette de données. Des simulations ont démontré que la résolution spatiale et la précision des données ont un impact significatif sur la précision de la mesure du changement dans l'indice de réfraction. Dans cette thèse, des résultats de simulations seront présentés afin de justifier les modifications à apporter au système expérimental et de démontrer l'amélioration prévue de la limite de détection du biocapteur spectro-angulaire par l'utilisation de caméras plus performantes. La nouvelle conception ainsi que les composantes choisis pour le système expérimental seront détaillées.

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Barrett, G. "Towards detection of endotoxin in high-purity water utilising a surface plasmon resonance biosensor." Thesis, Cranfield University, 2000. http://dspace.lib.cranfield.ac.uk/handle/1826/11094.

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The aims of this project were to develop a system for monitoring a continuous stream of high grade purified water for potential contamination by bacterial endotoxins. The monitoring system was to be designed so that it could be readily integrated within a closed water purification processing system. The project was viewed as a developmental stage towards the development of a commercial sensor with wide ranging applications within the pharmaceutical and environmental sectors. This text details the development of testing protocols for the examination of ultra pure water using different sensing matrices. The endotoxin structure is comprised of three main sections with specific chemistry. These regions have each been considered as potential areas for detection. The development of surface plasmon resonance (SPR) systems and protocols for the detection of endotoxin was shown both to be possible and practical within given experimental parameters. In order to assess the potential for this sensing within a more established experimental system and to further expand the potential sensing layers for endotoxins, further experiments were carried out using a BIAcore system. The use of the BIAcore allowed the examination of alternative sensing surfaces based on the specific nature of the endotoxin molecule rather than the use of literature based reactants that have previously displayed an affinity for the endotoxin molecules. The methods used within this project have concentrated on the overall chemistry of the endotoxin molecule. The potential binding/complexing agents have been targeted at the three principal regions of the endotoxin structure using the chemical nature of these regions as an attractive surface to the sensing layer.

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Barrett, Gary. "Towards detection of endotoxin in high-purity water utilising a surface plasmon resonance biosensor." Thesis, Cranfield University, 2000. http://dspace.lib.cranfield.ac.uk/handle/1826/11094.

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The aims of this project were to develop a system for monitoring a continuous stream of high grade purified water for potential contamination by bacterial endotoxins. The monitoring system was to be designed so that it could be readily integrated within a closed water purification processing system. The project was viewed as a developmental stage towards the development of a commercial sensor with wide ranging applications within the pharmaceutical and environmental sectors. This text details the development of testing protocols for the examination of ultra pure water using different sensing matrices. The endotoxin structure is comprised of three main sections with specific chemistry. These regions have each been considered as potential areas for detection. The development of surface plasmon resonance (SPR) systems and protocols for the detection of endotoxin was shown both to be possible and practical within given experimental parameters. In order to assess the potential for this sensing within a more established experimental system and to further expand the potential sensing layers for endotoxins, further experiments were carried out using a BIAcore system. The use of the BIAcore allowed the examination of alternative sensing surfaces based on the specific nature of the endotoxin molecule rather than the use of literature based reactants that have previously displayed an affinity for the endotoxin molecules. The methods used within this project have concentrated on the overall chemistry of the endotoxin molecule. The potential binding/complexing agents have been targeted at the three principal regions of the endotoxin structure using the chemical nature of these regions as an attractive surface to the sensing layer.

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Torrance, David. "Influence of the Local Dielectric Environment and its Spatial Symmetry on Metal Nanoparticle Surface Plasmon Resonances." Honors in the Major Thesis, University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/1195.

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This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf.edu/Systems/DigitalInitiatives/DigitalCollections/InternetDistributionConsentAgreementForm.pdf You may also contact the project coordinator, Kerri Bottorff, at kerri.bottorff@ucf.edu for more information. Bachelors Sciences Physics

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Singh, Meenakshi. "Nanostructured bioarchitectures for electrochemical and optical biosensor applications : design of a biocathode for biofuel cells." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENI107/document.

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Les avancées dans le domaine de l'analyse médicale et environnementale exigent des méthodes sensibles et précises pour la détection de molécules organiques nocives. Les travaux de recherche de cette thèse présentent un nouveau système d'affinité pour l'immobilisation de biorécepteurs, de nouvelles stratégies d'amplification du signal et de nouveaux nanomatériaux à base de modèles bio-inspirés afin d'améliorer les performances des biocapteurs ou des biopiles.Dans une première partie, un nouveau système d'affinité supramoléculaire entre la biotine et la beta-cyclodextrine a été étudié et a permis de déterminer une constante d'association de 3 x 10² L.mol-1. Ce système permet l'immobilisation d'une grande variété de biorécepteurs commerciaux marqués avec une biotine sur des surfaces éléctrogénérées pour l'élaboration de biocapteurs. Au-NPs modifiés par des beta-CD a été utilisé avec succès pour "optical antenna" pour l'amplification additionnelle du signal SPRi utilisant des marqueurs QD. La combinaison de ses nano-objets permettent la construction d'immunocapteurs ou de capteurs à ADN très sensible.Dans une deuxième partie, différentes variétés de nanomatériaux tels que les nanodiamants, les nanoparticules magnétiques, les nanotubes de carbone (CNT) et graphène ont été utilisé pour modifier la surface des transducteurs suivies par leur fonctionnalisation non-covalentes par des dérivés pyrène. Le nouveau dépôt de nanotubes « layer-by-layer » et les différentes tailles de nanoparticules avec des porosité variable présentent une approche flexible pour la construction de capteurs enzymatiques et d'immunocapteurs. Le graphène est un matériel d'épaisseur atomique qui doublent la sensibilité SPR pour la détection d'anticorps et d'antigène. Enfin, une réduction bioélectrocatalytique efficace de l'oxygène est reporté en utilisant des CNT fonctionnalisés par les pyrènes pour une application comme biocathode dans les biopiles The advancing field of medicine and environmental analysis demands sensitive and accurate methods for sensing harmful organic molecules The research work in this thesis presents a novel affinity system for immobilization of bioreceptors, a novel signal amplification strategy, and novel nanomaterials based bio-designs (architectures) with the improved biosensor or bio-fuel cell (bio-cathode) performances.Firstly, a new affinity system based on supramolecular host-guest interactions between biotin and & beta-CD with an association constant of 3 x 10² M-1 is studied. This allows immobilization of a variety of commercially available biotin labelled bioreceptors for biosensing application. beta-CD modified Au-NPs were successfully applied as optical antenna for additional SPRi signal amplification using QD labels. The beneficial effect of the combination of these nano-objects enables the construction of highly sensitive DNA or immunosensors.Secondly, various kinds of nanomaterials such as nanodiamonds, carbon nanotubes, magnetic nanoparticles, graphene and are employed to modify transducer surface followed by non-covalent functionalization with pyrene derivatives. The novel 3D layer-by-layer deposition of nanotubes and different sized nanoparticles with varying porosity presents a flexible approach towards construction of enzymatic or immuno-sensors. Graphene, a material with atomic thickness doubles the SPR sensitivity towards detection of antibody, anti-CT. Finally, an efficient bioelectrocatalytic reduction of oxygen is reported using pyrene functionalized CNT forest as a bio-cathode for bio-fuel cell applications

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Balasubramanian, Shankar Ganesh Sokkalinga Simonian Aleksandr L. "Development of smart functional surfaces for biosensor applications." Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/FALL/Materials_Engineering/Dissertation/Balasubramania_S%20G_2.pdf.

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Thesis (Ph. D.)--Auburn University, 2008. Abstract. Vita. The following patent resulted from the dissertation research: Davis, V., Simonian, A.L., Nepal, D., Balasubramanian, S, "Preparation of Precisely Controlled Thin Film Nanocomposites of Carbon Nanotubes and Biomaterials", U.S. Provisional Patent Application No. 61/000,938, filed on 30 October 2007. The following peer-reviewed publications resulted from the dissertation research: Dhriti Nepal, Shankar Balasubramanian, Aleksandr Simonian, and Virginia Davis, "Mechanically Strong Antibacterial Thin Film Based on Single-Walled Carbon Nanotubes Armored with Biopolymers", Nano Letters ASAP article, May 2008 (# equal contribution) -- Shankar Balasubramanian, Iryna B. Sorokulova, Vitaly J. Vodyanoy, and Aleksandr L. Simonian, "Lytic Phage as a Specific and Selective Probe For Detection of Staphylococcus Aureus: A Surface Plasmon Resonance Spectroscopic Study", Biosensors and Bioelectronics, 2007, 22, 948-955 -- Shankar Balasubramanian, Alexander Revzin, Aleksandr Simonian, "Electrochemical Desorption of Proteins from Gold Electrode Surface", Electroanalysis, 2006, 18, 1885-1892 (Invited article) -- Vishwaprakash Nanduri, Shankar Balasubramanian, Srinivas Sista, Vitaly J. Vodyanoy, and Aleksandr L. Simonian, "Highly Sensitive Phage-based Biosensor for the Detection of ß-galactosidase", Analytica Chimica Acta, 2007, 589, 166- 172 -- H. Luckarift, Shankar Balasubramanian, S. Paliwal, G. Johnson and A. Simonian, "Enzyme-Encapsulated Silica Monolayers For Rapid Functionalization of a Gold Surface", Colloids and Surfaces B: Biointerfaces, 2007, 58, 28-33 (Invited article) -- Dong Wei, Omar Oyarzabal, Tung-Shi Huang, Shankar Balasubramanian, Srinivas Sista, Aleksandr Simonian, "Development of Surface Plasmon Resonance Biosensor For The Identification of Campylobacter jejuni", Journal of Microbiological Methods, 2007, 69, 78-85. The following conferences presentations resulted from the dissertation research: Covalent Immobilization of Organophosphorus Hydrolase on Carbon Nanotubes for Biosensor Applications, accepted for oral presentation at 12th International Meeting on Chemical Sensors, Jul. 13-16, 2008, Columbus, OH -- Electrochemical characteristics of SWNT-biopolymer nanocomposites, accepted for 213th meeting of The Electrochemical Society, May 18-23, 2008, Phoenix, AR -- Mechanically Robust Antibacterial Thin Films Composed of Single-Walled Carbon Nanotubes and Biopolymers, 2008 AIChE Spring National Meeting, Apr. 6-10, New Orleans, LA -- Production and characterization of protein and DNA based single wall carbon nanocomposites by layer-by-layer assembly, MRS Fall Meeting, Nov. 26-30, 2007, Boston, MA -- Gold surface modified with enzyme-encapsulated silica monolayers for biosensor application, The 58th Southeast Regional Meeting of the American Chemical Society, Nov. 1-4, 2006, Augusta, GA -- Electrochemical modulation of biological interfaces, 209th meeting of The Electrochemical Society, May 7-12, 2006, Denver, CO -- SPR based biosensor using lytic phage as a specific and selective probe for staphylococcus aureus detection, 57th Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy, Mar. 12-17, 2006, Orlando, FL -- Specific & selective detection of staphylococcus aureus by lytic phage using SPR biosensor, 57th Southeast / 61st Southwest Joint Regional Meeting of the American Chemical Society, Nov. 1-4, 2005, Memphis, TN -- Prevention of non-specific binding as a way to increase sensitivity of SPR-based sensors, 206th meeting of The Electrochemical Society, October 3-8, 2004, Honolulu, HI. Includes bibliographical references.

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Danilov, Artem. "Design, characterisation and biosensing applications of nanoperiodic plasmonic metamaterials." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0110/document.

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Cette thèse considère de nouvelles architectures prometteuses des métamatériaux plasmoniques pour biosensing, comprenant: (I) des réseaux périodiques 2D de nanoparticules d'Au, qui peuvent supporter des résonances des réseaux de surface couplées de manière diffractive; (II) Reseaux 3D à base de cristaux plasmoniques du type d'assemblage de bois. Une étude systématique des conditions d'excitation plasmonique, des propriétés et de la sensibilité à l'environnement local dans ces géométries métamatérielles est présentée. On montre que de tels réseaux peuvent combiner une très haute sensibilité spectrale (400 nm / RIU et 2600 nm / RIU, ensemble respectivement) et une sensibilité de phase exceptionnellement élevée (> 105 deg./RIU) et peuvent être utilisés pour améliorer l'état actuel de la technologie de biosensing the-art. Enfin, on propose une méthode de sondage du champ électrique excité par des nanostructures plasmoniques (nanoparticules uniques, dimères). On suppose que cette méthode aidera à concevoir des structures pour SERS (La spectroscopie du type Raman à surface renforcée), qui peut être utilisée comme une chaîne d'information supplémentaire à un biocapteur de transduction optique This thesis consideres novel promissing architechtures of plasmonic metamaterial for biosensing, including: (I) 2D periodic arrays of Au nanoparticles, which can support diffractively coupled surface lattice resonances; (II) 3D periodic arrays based on woodpile-assembly plasmonic crystals, which can support novel delocalized plasmonic modes over 3D structure. A systematic study of conditions of plasmon excitation, properties and sensitivity to local environment is presented. It is shown that such arrays can combine very high spectral sensitivity (400nm/RIU and 2600 nm/RIU, respectively) and exceptionally high phase sensitivity (> 105 deg./RIU) and can be used for the improvement of current state-of-the-art biosensing technology. Finally, a method for probing electric field excited by plasmonic nanostructures (single nanoparticles, dimers) is proposed. It is implied that this method will help to design structures for SERS, which will later be used as an additional informational channel for biosensing

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"Surface plasmon enhanced effects in photonic biosensors." Thesis, 2008. http://library.cuhk.edu.hk/record=b6074665.

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Detection of oligonucleotide target has been performed with a sandwich assay scheme. We compare the detection performance of strategies using probe oligonucleotide with or without gold nanoparticles (Au-NPs, 20nm) capped on 3'. Our experimental results reveal that while the DNA detection implemented with NIS can provide high sensitivity, both dynamic range and detection limit can be amplified with the aid of Au-NPs on 3' of the probes. The current detection limits of NIS with and without Au-NPs are 0.4 femtomole and 1 nanomole respectively. (Abstract shortened by UMI.) Finally, this work presents a systematic study of the surface-enhanced Raman-scattering (SERS) properties of nanoparticle island substrates (NIS) and their application for oligonucleotide target detection. To effectively implement SERS on NIS and identify an optimal condition for DNA detection, the relationship between extinction maximum (lambdamax) and SERS enhancement factor (EF) will be explored in detail. This work demonstrates high S/N ratio SERS spectra can be achieved with NIS that has lambdamax located within a spectral window (&sim;60nm) defined by the excitation wavelength (514nm) and the scattered Raman wavelength. The highest EF measured is about 4x10 8 with a thickness of Ag being 50 A. In addition, a surface plasmon enhanced ellipsometry (SPEE) biosensor scheme based on the use of a photoelastic modulator (PEM) has been explored. We showed that the polarization parameters of a laser beam, tan psi, cos Delta and ellipse orientation angle &phis;, can be directly measured by detecting the modulation signals at the 1st and 2nd harmonics of the modulation frequency under a certain birefringence geometry. This leads to an accurate measurement of refractive index variations within the evanescent field region close to the gold sensor surface, thereby enabling biosensing applications. Our experimental results confirm that the new scheme offers a decent detection limit of 2x10-7 refractive index unit (RIU) or 5ng/ml of biomolecule solute concentration without any compromise in dynamic range. We have demonstrated that the sensitivity limit of intensity-based SPR biosensors can be enhanced when we combine the contributions from phase with that of amplitude instead of just detecting the amplitude or phase variation only. Experimental results indicate that an enhancement factor of as much as 20 times is achievable, yet with no compromise in measurement dynamic range. While existing SPR biosensor systems are predominantly based on the angular scheme, which relies on detecting intensity variations associated with amplitude changes only, the proposed scheme may serve as a direct system upgrade approach for these systems. We have developed a novel design of multi-pass surface plasmon resonance (SPR) biosensor with differential phase interrogation based on multi-pass interferometry. This new configuration provides an intrinsic phase amplification effect of over two-fold by placing the SPR sensor head in a signal arm of the interferometer so that the interrogating optical beam will traverse the sensor surface infinite number of times. Experimental interferometers based on the Michelson and Fabry-Perot configurations have been employed to experimentally verify this amplification effect through the comparison with the Mach-Zehnder configuration. Results obtained from the salt-water mixtures, antibody-antigen, and protein-DNA binding reaction have confirmed the expected phase measurement enhancement. Yuan, Wu. Adviser: H. P. Ho. Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3582. Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. Includes bibliographical references (leaves 115-132). Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. Abstracts in English and Chinese. School code: 1307.

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Luo, Yu-Tang, and 羅鈺棠. "Stabilization of nitride-base surface plasmon resonance biosensors." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/yb3z8k.

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碩士 國立中央大學 光電科學與工程學系 107 The surface plasma biosensor built with nitride quantum wells (QWs) is of many advantages, including simplified structure and enhanced sensitivity. Although the surface plasma resonance (SPR) phenomenon induced by Ag on blue-emitting QWs can achieve high enhancement in photoluminescence (PL) spectrum intensity, the instability of Ag hinders the practical applications. In this study, we investigated various structures to stabilize the Ag layer. In addition, we applied different annealing and alloying conditions in the device fabrication. It is found that the Ag annealed at 500 ºC and Al layer can effectively mitigate the oxidation/sulfuration issues of Ag layer. Raman spectroscopy differs from PL spectroscopy in that it can see the corresponding peak signal of the sample in its spectrum on the measured sample. In this study, deoxyribonucleic acid (DNA) molecules were dropped on a micro-roughened QW epi-wafer, and the appropriate metal was used to achieve surface-enhanced Raman scattering (SERS). The SERS spectrum of diluted DNA solutions showed that the characteristic DNA signals can still be observed at the molar concentration down to the 10-5 M.

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Wu, Sheng-Hung, and 吳昇紘. "Development of Disposable Localized Surface Plasmon Resonance Biosensors." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/51545500391791637000.

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Joe, Shen-Fen, and 卓聖芬. "Surface plasmon resonance biosensor." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/34126801039058146358.

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博士 國防大學中正理工學院 國防科學研究所 95 Surface plasmon resonance (SPR) is a collective oscillation of electrons in the surface of the metal. It is sensitive to the changes of the dielectric medium near the metal surface and can be used to detect the refractive index of the medium. In this dissertation, a biosensor combined with the common path heterodyne interferometry and the SPR technique is developed. The phase difference of the reflected light between TM and TE waves from the sensor chip is measured. To construct this high sensitive SPR biosensor system, a heterodyne light source is adopted. The light source is polarized and split into two beams, one is TE wave and the other is TM wave. These beams are modulated by individual acoustic optical modulator(AOM) and then combined as heterodyne light sources with frequency difference of 60 kHz by another PBS. This common path heterodyne interferometry construction has advantages of less external-disturbance and real-time measurement. There are three parts of this dissertation: (1) Design a common path heterodyne interferometry SPR system, and then use it to detect the refractive index change on the sensor surface to obtain detection limit. (2) Monitor the interactions of sheep IgG and anti- sheep IgG by using of the correspondent phase measurement. (3) Calculate the association and dissociation rate constant of sheep IgG and anti- sheep IgG. As a whole, the measurement results show that this proposed SPR sensor system has proven a high sensitivity in detecting the refractive index changes of the sheep IgG and anti- sheep IgG interactions. Keywords：surface plasmon resonance, phase measurement, biosensor.

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Huang, Kai-Lin, and 黃凱麟. "Theoretical Analyses on Nitride-based Surface Plasmon Resonance Biosensors." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/24512406121164024611.

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碩士 國立中央大學 光電科學與工程學系 105 Surface plasmon resonance (SPR) is the collective electron oscillation at the interface of metal and dielectric material. The SPR effect is highly sensitive to the change of surface refractive index, and therefore can be used to detect biomolecular binding events between the antibody and the antigen. In this research, we present theoretical analyses on the potential of nitride-based SPR structure in biosensing applications. The SPR effect is achieved with a GaN/InGaN/GaN quantum well and a thin Ag layer, and the change in surface refractive index is detected by the varied emission intensity from the quantum well. The nitride epilayers were grown with metal-organic chemical vapor deposition (MOCVD). The MOCVD technique can easily produce wafer-scale nanostructures that are suitable for single-molecule detection with the surface enhanced Raman scattering (SERS) effect. With the calculated dispersion curves and the penetration depths estimated by the finite-difference time-domain method, we demonstrate the advantages of this novel SPR biosensing structure, which are not attainable with the conventional Kretschmann configuration.

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"Surface plasmon resonance photonic biosensors based on phase-sensitive measurement techniques." 2005. http://library.cuhk.edu.hk/record=b5892392.

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Law Wing Cheung. Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. Includes bibliographical references. Abstracts in English and Chinese. Abstract --- p.I Acknowledgements --- p.V List of Publications related to this project --- p.VI Contents --- p.VII Chapter Chapter 1 --- Introduction --- p.1-1 Chapter Chapter 2 --- Literature Review Chapter 2.1 --- Surface Plasmon Waves --- p.2-2 Chapter 2.2 --- Excitation of Surface Plasmon --- p.2-4 Chapter 2.2.1 --- Surface Plasmon Coupling Schemes --- p.2-6 Chapter 2.3 --- Detection Techniques used in SPR sensors --- p.2-13 Chapter 2.3.1 --- Angular Interrogation --- p.2-14 Chapter 2.3.2 --- Wavelength Interrogation --- p.2-15 Chapter 2.3.3 --- Intensity Interrogation --- p.2-16 Chapter 2.3.4 --- Phase Interrogation --- p.2-16 Chapter 2.3.5 --- Commercial SPR biosensors --- p.2-18 Chapter 2.3.6 --- Comparison between Detection Techniques --- p.2-19 Chapter 2.4 --- Applications of SPR biosensors --- p.2-21 Chapter Chapter 3 --- Principle of Surface Plasmon Resonance Sensing Technology Chapter 3.1 --- SPR Phenomenon --- p.3-1 Chapter 3.2 --- Conditions for Surface Plasmon Resonance --- p.3-5 Chapter 3.3 --- Wave-vectors --- p.3-7 Chapter 3.4 --- Surface Plasmon Resonance described by Fresnel's Theory --- p.3-8 Chapter 3.5 --- Concept of Surface Plasmon Resonance Biosensing --- p.3-10 Chapter Chapter 4 --- Experiments Chapter 4.1 --- Highly sensitive differential phase-sensitive surface plasmon resonance biosensor based on Mach-Zehnder configuration --- p.4-1 Chapter 4.1.1 --- Materials required --- p.4-1 Chapter 4.1.2 --- Experimental Setup --- p.4-2 Chapter 4.1.3 --- Principle of Differential Phase Measurement --- p.4-3 Chapter 4.1.4 --- Photodetector Circuitry --- p.4-6 Chapter 4.1.5 --- Digital Signal Processing --- p.4-7 Chapter 4.1.6 --- Polymer based Micro-fluidic System Integrated with SPR Biosensor --- p.4-9 Chapter 4.2 --- Phase-sensitive Surface Plasmon Resonance Biosensor using the Photoelastic Modulation Technique --- p.4-12 Chapter 4.2.1 --- Materials required --- p.4-12 Chapter 4.2.2 --- Experimental Setup --- p.4-13 Chapter 4.2.3 --- Principle of Photoelastic Modulation Technique and Signal Processing --- p.4-14 Chapter 4.2.4 --- Operation Principle of Photoelastic Modulator --- p.4-17 Chapter 4.3 --- Sample Preparations --- p.4-18 Chapter 4.3.1 --- Glycerin-water Mixtures --- p.4-18 Chapter 4.3.2 --- "PBS, BSA and BSA antibody" --- p.4-19 Chapter 4.3.3 --- "RPMI, Trypsin, Cells and SDS" --- p.4-20 Chapter Chapter5 --- Results amd Discussions Chapter 5.1 --- Experimental setup I: Highly sensitive differential phase-sensitive surface plasmon resonance biosensor based on Mach-Zehnder configuration --- p.5-1 Chapter 5.1.1 --- Measuring various glycerin-water concentration mixture with silver-gold sensing layer --- p.5-1 Chapter 5.1.2 --- Comparison between the sensitivity of our setup and reported setup based on phase detection --- p.5-4 Chapter 5.1.3 --- Discussion on 0.01° system resolution --- p.5-7 Chapter 5.1.4 --- Experiment on monitoring BSA-BSA antibody binding reaction --- p.5-9 Chapter 5.1.5 --- Matching oil and glass slide --- p.5-11 Chapter 5.1.6 --- Experiments on monitoring BSA-BSA antibody binding reaction with integrated microfluidic system --- p.5-12 Chapter 5.1.7 --- Experiment on observing cell adhesion properties on gold surface under the influence of trypsin --- p.5-14 Chapter 5.1.8 --- Discussion on the non-specific binding between trypsin and gold surface --- p.5-16 Chapter 5.1.9 --- Modifying the gold surface with BSA layer --- p.5-17 Chapter 5.1.10 --- Experiment on observing cell adhesion properties on the gold surface under the influence Sodium Dodecyl Sulfate (SDS) --- p.5-18 Chapter 5.2 --- Experimental setup II: Phase-sensitive surface plasmon resonance biosensor using the photoelastic modulation technique --- p.5-21 Chapter 5.2.1 --- Measurement on difference glycerin-water concentration mixture --- p.5-21 Chapter 5.2.2 --- Experiment on monitoring BSA-BSA antibody binding reaction --- p.5-23 Chapter Chapter 6 --- Conclusions and Future Works Chapter 6.1 --- Conclusions --- p.6-1 Chapter 6.2 --- Future Works --- p.6-2 References --- p.R-1 Appendix Chapter A. --- Phase Extraction Routine written by Matlab --- p.A-1 Chapter B. --- Mathematical expressions for calculating the phase angle in the experiment of SPR biosensor using the Photoelastic Modulation Technique --- p.A-6 Chapter C. --- Relationship between Concentration and Refractive Index of Glycerin-Water Mixture --- p.A-11 Chapter D. --- Physical Properties of Bovine Serum Albumin --- p.A-12 Chapter E. --- Simulation Curve written by Matlab --- p.A-13

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Huang, Teng-Yi, and 黃騰毅. "Development of Graphene Oxide Sheets for Surface Plasmon Resonance Biosensors." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/68131920134228431119.

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碩士 國立臺灣師範大學 光電科技研究所 101 The advantage of surface plasmon resonance (SPR) biosensors includes high sensitivity, label-free, and real-time detection. These advantage leading SPR biosensors to identified as one of the most important optical detection methods for biomolecules. The goal of this thesis is to develop graphene oxide (GO) sheets SPR biosensor that used GO as sensing layer for biomolecules detection. First, we used cystamine as linker layer, forming Cys film by self-assembled monolayer (SAM) technique. Then, GO solution was immobilized on the surface of Cys film through covalent attachment, forming GO sheets. The GO sheets SPR biosensor was used to detect the dynamic interactions of biomolecules and antibody-antigen. For experimental verification of this system, bovine serum albumin (BSA) and LAMP DNA products were used to demonstrate by GO sheets and conventional Au films. We also compared these two films by sensitivity, detection limits and kinetic analysis. The sensitivity of GO sheets that can be determined by this thesis is about 12-fold higher than that obtained with the sensor based on conventional Au films. The detection limits and the results of kinetic analysis of GO sheets were also better than conventional Au films. Most important of all, GO sheets have the ability for directly detect biomolecules, skipped the immunization interactions, leading to a low cost experiment. We anticipate that graphene oxide sheet SPR biosensors will not only enable for possible applications for biomedicine and diseases but also have wide spectrum of application in pharmaceutical industry, environmental monitoring, and agriculture in the near future.

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Chien, Fan-Ching, and 簡汎清. "Design and fabrication of ultrahigh-resolution surface plasmon resonance biosensors." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/44460806366531252281.

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碩士 國立中央大學 機械工程研究所 91 Theoretically, simulate and compare the sensitivity of any mode of the existing thin film surface plasmon resonance (SPR) biosensors. No matter which mode of the existing thin film SPR biosensors such as convential SPR biosesor, couple plasmon-waveguide resonance (CPWR) biosesor, and long-range surface plasmon resonance (LRSPR) biosesor, the detection resolution is limited to approximately 1 pg/mm2 of biomolecular surface coverage. Under this constrain, small biomolecular interactions in low concentration are hard to be analyzed. Hence, by increasing the enhancement factor of SPR through metal nanoparticles and eliminating sensing noise with the optical differential metrology system, we demonstrate the resolution of Nanoparticle-enhanced SPR biosensors for detecting the surface coverage of biomaterial down to 100 fg/mm2. The novel nanoparticle-enhanced ultrahigh-resolution SPR biosensors are designed based on the Maxwell-Garnett model and Fresnel equations, and are fabricated by using the RF co-sputter deposition. Therefore, the nanoparticle-enhanced ultrahigh-resolution SPR biosensors can directly analyze tiny biomolecular interactions without adding labels and they will likely become the most important sensing device in the field of biomolecular diagnosis. About biomolecular interaction analysis (BIA), focus on the kinetics of DNA hybridization, then also utilize electric field to reduce time of hybridization and will be able to speed up the rate of detection of biochip greatly, the fundamental study of adsorption kinetics of protein molecules. Furthermore, apply this technology to detection of novel molecular imprinted polymer (MIP) chip. Provide systematical information of interaction mechanism and kinetics of processes of biomolecules and advance the ability of drug design, proteomics study.

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Zhao, Sandy Shuo. "Detection of methotrexate using surface plasmon resonance biosensors for chemotherapy monitoring." Thèse, 2013. http://hdl.handle.net/1866/10792.

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Le méthotrexate (MTX), un agent anti-cancéreux fréquemment utilisé en chimiothérapie, requiert généralement un suivi thérapeutique de la médication (Therapeutic Drug Monitoring, TDM) pour surveiller son niveau sanguin chez le patient afin de maximiser son efficacité tout en limitant ses effets secondaires. Malgré la fenêtre thérapeutique étroite entre l’efficacité et la toxicité, le MTX reste, à ce jour, un des agents anti-cancéreux les plus utilisés au monde. Les techniques analytiques existantes pour le TDM du MTX sont coûteuses, requièrent temps et efforts, sans nécessairement fournir promptement les résultats dans le délai requis. Afin d’accélérer le processus de dosage du MTX en TDM, une stratégie a été proposée basée sur un essai compétitif caractérisé principalement par le couplage plasmonique d’une surface métallique et de nanoparticules d’or. Plus précisément, l’essai quantitatif exploite la réaction de compétition entre le MTX et une nanoparticule d’or fonctionnalisée avec l’acide folique (FA-AuNP) ayant une affinité pour un récepteur moléculaire, la réductase humaine de dihydrofolate (hDHFR), une enzyme associée aux maladies prolifératives. Le MTX libre mixé avec les FA-AuNP, entre en compétition pour les sites de liaison de hDHFR immobilisés sur une surface active en SPR ou libres en solution. Par la suite, les FA-AuNP liées au hDHFR fournissent une amplification du signal qui est inversement proportionnelle à la concentration de MTX. La résonance des plasmons de surface (SPR) est généralement utilisée comme une technique spectroscopique pour l’interrogation des interactions biomoléculaires. Les instruments SPR commerciaux sont généralement retrouvés dans les grands laboratoires d’analyse. Ils sont également encombrants, coûteux et manquent de sélectivité dans les analyses en matrice complexe. De plus, ceux-ci n’ont pas encore démontré de l’adaptabilité en milieu clinique. Par ailleurs, les analyses SPR des petites molécules comme les médicaments n’ont pas été explorés de manière intensive dû au défi posé par le manque de la sensibilité de la technique pour cette classe de molécules. Les développements récents en science des matériaux et chimie de surfaces exploitant l’intégration des nanoparticules d’or pour l’amplification de la réponse SPR et la chimie de surface peptidique ont démontré le potentiel de franchir les limites posées par le manque de sensibilité et l’adsorption non-spécifique pour les analyses directes dans les milieux biologiques. Ces nouveaux concepts de la technologie SPR seront incorporés à un système SPR miniaturisé et compact pour exécuter des analyses rapides, fiables et sensibles pour le suivi du niveau du MTX dans le sérum de patients durant les traitements de chimiothérapie. L’objectif de cette thèse est d’explorer différentes stratégies pour améliorer l’analyse des médicaments dans les milieux complexes par les biocapteurs SPR et de mettre en perspective le potentiel des biocapteurs SPR comme un outil utile pour le TDM dans le laboratoire clinique ou au chevet du patient. Pour atteindre ces objectifs, un essai compétitif colorimétrique basé sur la résonance des plasmons de surface localisée (LSPR) pour le MTX fut établi avec des nanoparticules d’or marquées avec du FA. Ensuite, cet essai compétitif colorimétrique en solution fut adapté à une plateforme SPR. Pour les deux essais développés, la sensibilité, sélectivité, limite de détection, l’optimisation de la gamme dynamique et l’analyse du MTX dans les milieux complexes ont été inspectés. De plus, le prototype de la plateforme SPR miniaturisée fut validé par sa performance équivalente aux systèmes SPR existants ainsi que son utilité pour analyser les échantillons cliniques des patients sous chimiothérapie du MTX. Les concentrations de MTX obtenues par le prototype furent comparées avec des techniques standards, soit un essai immunologique basé sur la polarisation en fluorescence (FPIA) et la chromatographie liquide couplée avec de la spectrométrie de masse en tandem (LC-MS/MS) pour valider l’utilité du prototype comme un outil clinique pour les tests rapides de quantification du MTX. En dernier lieu, le déploiement du prototype à un laboratoire de biochimie dans un hôpital démontre l’énorme potentiel des biocapteurs SPR pour utilisation en milieux clinique. Methotrexate (MTX) cancer therapy requires therapeutic drug monitoring (TDM) for following its levels in a patient during the course of treatment in order to maximize efficacy while minimizing side effects. Despite its narrow therapeutic window, MTX remains until this date, one of the most employed chemotherapy agents. Existing TDM analytical techniques for MTX are costly, time-consuming and labor intensive which are not suitable to promptly generate results within the therapy timeframe. To provide rapid MTX quantification for TDM, a strategy is proposed based on a competitive assay featuring gold nanoparticles and surface plasmonic coupling. More specifically, the inhibition of MTX with its molecular receptor, human dihydrofolate reductase (hDHFR), an enzyme associated with proliferative diseases, is explored. Free MTX mixed with folic acid-functionalized gold nanoparticles (FA-AuNP) are in competition for hDHFR binding sites immobilized on a SPR active surface or free in solution. FA-AuNP binding to hDHFR provides signal amplification which is inversely proportional to the concentration of MTX. Surface plasmon resonance (SPR) is commonly used as a spectroscopic technique for the interrogation of biomolecular interactions. Current commercial SPR instruments are laboratory-based, bulky, expensive, lack sensitivity in complex matrix and have not shown adaptability in clinical settings. In addition, SPR analysis of small molecules such as drugs has not been extensively explored due to lack of sensitivity. The recent advances in materials science and surface chemistry exploiting gold nanoparticle integration for SPR response enhancement and peptide surface chemistry have shown potential in overcoming the poor sensitivity and surface-fouling limitations for crude biofluids analysis. These novel concepts of SPR technology are incorporated with a miniaturized fully integrated SPR prototype to conduct fast, reliable and sensitive analysis to monitor MTX levels of a patient undergoing chemotherapy. The objective of the thesis is to explore different strategies in improving drug analysis in a complex matrix using SPR biosensors and to put in perspective of the potential of SPR biosensors as a useful TDM tool in clinical laboratories or at a point-of-care situation. To achieve these objectives, a colorimetric solution-based MTX competitive assay is first established with FA-AuNP. Then, the solution-based MTX competitive assay is translated onto a SPR platform. For both developed assays, sensitivity, selectivity, detection limit, dynamic range optimization as well as analysis of methotrexate in complex matrix are inspected. Furthermore, the SPR prototype is validated by its equivalent performance to existing SPR systems and by its utility in executing MTX analysis in actual serum samples from patients undergoing chemotherapy. The concentrations of MTX obtained by SPR biosensing are compared to standard techniques: fluorescence polarization immunoassay (FPIA) and liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) in order to confirm the feasibility of SPR biosensors as a useful clinical tool for performing rapid MTX concentration evaluation. Finally, the successful deployment of the prototype to a hospital laboratory demonstrates enormous prospective of SPR biosensors in clinical use.

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Fan, Shi-Yuan, and 范仕遠. "Ultra Sensitivity of Carboxylated Graphene Oxide for Surface Plasmon Resonance Biosensors." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/9sgx8z.

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碩士 國立臺灣師範大學 光電科技研究所 105 In this paper we proved that carboxyl-functionalized graphene oxide (GO-COOH) was used to detect pancreatic cancer indicator protein 19-9 with surface plasmon resonance (SPR) (Carbohydrate Antigen, CA19-9). We compare the sensitivity of GO-COOH biosensor、GO biosensor and traditional biosensor with bovine serum albumin. Next to detected CA19-9 by the highest sensitivity of GO-COOH biosensor. GO-COOH, graphene oxide (GO) and graphene were discussed with conductivity、SPR angular displacement sensitivity (S_RI) and adsorption efficiency of biomolecules. GO-COOH has better conductivity than GO because the carboxyl group is more flexible with carbon chain than other oxygen-containing functional groups and allows the charge carrier to move more easily along the carbon chain. The enhancement of conductivity increases the propagation constant of the surface plasma polarization, which is proportional to S_RI, and uses the SPR system to verify that GO-COOH is better than GO. Multifunctional plasmonic system (MPS) was been used to observe the characteristics of GO-COOH at the SPR angle of 640 mn-700 nm. The penetrating spectroscopy system and the Scanning electron microscope (SEM) were used to observe the properties of the GO-COOH bond on the chip. Experiment of SPR system is proved that GO-COOH-based surface plasmon resonance biochip has high sensitivity and low detection limit when detecting Anti-Bovine Albumin antibody (anti-BSA). 0.275 mg/ml GO-COOH biochip was 2.1 times better than the 2 mg/ml GO chip. In addition, the limit of detection of GO-COOH biochip low to 10 fg/ml in the detection of anti-BSA, significantly better than traditional biochip. Finally, the SPR system was used to detect the CA19-9 immune response. Previous literature indicates that 79% of patients with pancreatic cancer contains CA19-9 above 37 units/ml. The results show that the lowest antigen detection limit of GO-COOH as the biomaterial is 10 unit/ml. Based on the experimental results of this paper, the surface plasmon resonance biochip with GO-COOH as the biomaterial can be used in clinical diagnosis and widely used in the pharmaceutical industry, agriculture and environmental testing, and greatly improve the health quality of people.

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Dissertations / Theses on the topic 'Biosensors Surface plasmon resonance'

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