Дисертації: "Optical Biosensing"

1

King, Branden Joel. "Tapered Optical Fiber Platform for Biosensing Applications." University of Dayton / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1398708775.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

2

Blyth, David John. "Optical biosensing using sol-gel technology." Thesis, University of East Anglia, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338063.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

3

Greenhalgh, Andrew Bryce. "Tapered polymer optical fibres for biosensing." Thesis, Manchester Metropolitan University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.423074.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

4

D'Imperio, Luke A. "Biosensing-inspired Nanostructures:." Thesis, Boston College, 2019. http://hdl.handle.net/2345/bc-ir:108627.

Повний текст джерела

Анотація:

Thesis advisor: Michael J. Naughton
Nanoscale biosensing devices improve and enable detection mechanisms by taking advantage of properties inherent to nanoscale structures. This thesis primarily describes the development, characterization and application of two such nanoscale structures. Namely, these two biosensing devices discussed herein are (1) an extended-core coaxial nanogap electrode array, the ‘ECC’ and (2) a plasmonic resonance optical filter array, the ‘plasmonic halo’. For the former project, I discuss the materials and processing considerations that were involved in the making of the ECC device, including the nanoscale fabrication, experimental apparatuses, and the chemical and biological materials involved. I summarize the ECC sensitivity that was superior to those of conventional detection methods and proof-of-concept bio-functionalization of the sensing device. For the latter project, I discuss the path of designing a biosensing device based on the plasmonic properties observed in the plasmonic halo, including the plasmonic structures, materials, fabrication, experimental equipment, and the biological materials and protocols
Thesis (PhD) — Boston College, 2019
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Physics

Стилі APA, Harvard, Vancouver, ISO та ін.

5

Jamali, Abdul Aleem [Verfasser]. "Optical Antennas for Biosensing Applications / Abdul Aleem Jamali." Kassel : Universitätsbibliothek Kassel, 2015. http://d-nb.info/1073856577/34.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

6

Krasovska, Inese. "Optical Properties of Silicon Nanopillar Arrays for Biosensing." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-175760.

Повний текст джерела

Анотація:

Biosensing is currently a growing research field which is relevant for different applications, for instance in health care. Sensitive and cheap biosensors are required, preferably as simple as possible in their working principle. In this work Si nanopillar structures have been fabricated and used to show the sensing principle by both depositing oxide layers with different thicknesses and by using the biotinstreptavidin model system. Si nanopillars were fabricated by two different surface patterning methods – colloidal lithography and nanoimprint lithography (obtained from a commercial source). For colloidal lithography, a modified drop-coating technique as well as a spin-coating technique is used to make self-assembled silicon dioxide (SiO2) monolayers. It is shown that SiO2 particles with sizes of 0.5 μm and 1.0 μm form even monolayers across areas of ~2 mm2 (sufficient for optical measurements) after optimizing the spin-coating parameters. Particle size reduction is done by using reactive ion etching (RIE) and nanopillars with heights of 1.0 μm to 1.5 μm are etched by inductively coupled plasma RIE (ICP RIE). Spectrally resolved reflectance from the nanopillar arrays, often show distinct reflectance peaks. Depending on the nanopillar geometry, the wavelength position of the reflectance peaks can be sensitive to changes in the refractive index at the nanopillar surface, for example by attached bio-molecules or by a thin dielectric (e.g. silicon-di-oxide) surface layer. In order to simulate the effect of a surface-bio layer on the optical properties of the nanopillar arrays, silicon-di-oxide coated Si nanopillars were investigated experimentally and theoretically. The simulated reflectance spectra, obtained by Lumerical FDTD, show that the spectral shifts of the reflectance peaks grow linearly with the layer thickness. The deposition of the oxide layers is done by plasma-enhanced chemical vapor deposition (PECVD). While this technique is reliable for planar surfaces, pillar structures showed both a much reduced side-wall oxide thickness as well as oxide pile-up on the top of the pillars. However, by thermally driven material reflow it was possible, though not completely, to redistribute the piled-up oxide from the pillar top to the sidewalls. Reflectance from Si nanopillar structures was investigated primarily using UV-vis-NIR spectrophotometer. However, ellipsometry and Fourier transform infrared spectroscopy were also used for comparison. The experimental results of the oxide layer deposition on Si nanopillars show a maximum spectral shift of 4.6 nm per every 10 nm of deposited SiO2. 3 Moreover, the obtained linear behavior of the spectral shift with oxide thickness is similar to the simulated one. In order to use the biotin-streptavidin model system to demonstrate the sensing principle with Si nanopillar structures, a surface functionalization protocol was optimized on the planar SiO2 coated Si surface. As it turns out, both an anhydrous environment and water presence during the surface silanization prior to biotinilation are acceptable and lead to similar results. Further work is necessary for effective surface functionalization of nanopillars. However, preliminary investigations of (test structures) nanopillar arrays surface functionalized by biotinstreptavidin showed spectral shifts. The sensitivity was not sufficient to perform a full assay. Optimization of the nanopillar geometry for high surface sensitivity as well as improvement in the surface functionalization process are required to produce a sensitive biosensor.

Стилі APA, Harvard, Vancouver, ISO та ін.

7

Chung, Chun Lam Cathy K. S. "Optical biosensing of iron(III) in oceanic waters." Thesis, University of East Anglia, 2004. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.405393.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

8

Barreau, Stephanie. "Biosensing with sol-gel-immobilised proteins." Thesis, Loughborough University, 1999. https://dspace.lboro.ac.uk/2134/27275.

Повний текст джерела

Анотація:

Low temperature-processed, porous sol-gel glasses represent a new class of materials for the immobilisation of biomolecules. If used to entrap biological recognition elements, these transparent and chemically inert glasses offer a new approach in the development of optical biosensors.

Стилі APA, Harvard, Vancouver, ISO та ін.

9

Oleksiy, Krupin. "Biosensing Using Long-Range Surface Plasmon-Polariton Waveguides." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34210.

Повний текст джерела

Анотація:

Specific detection of biological matter is one of the key elements in a wide range of modern fields such as food industry, medicine, environmental and pharmaceutical industries. Generally, current common methods of detection (e.g. ELISA) involve molecular labelling, requirements for well-trained personnel and lengthy experimental procedures such as bacteria culture. All of the above issues result in high costs for biological analysis, and consequently, high costs for medical service, therapeutic drugs and various food products. Biosensors, on the other hand, can provide quick and cheap solutions to these problems. The field of optical biosensors is dominated by the method of surface plasmon resonance, which so far has attracted a lot of attention in the pharmaceutical industry. Investigation of long-range surface plasmon-polariton waveguides as an application for biosensing is still very novel, and most of it exists in the venue of theoretical discussions and modelling. The objective of this thesis is to demonstrate the capability of the novel optical biosensor based on plasmonic waveguides to selectively detect various biological entities in solutions. The experiments were conducted on photolithographically fabricated sensors consisting of straight gold waveguides embedded in low-refractive index fluoropolymer CYTOP and a microfluidic channel. As a proof-of-concept, a demonstration of basic sensing experiments such as detection of change in refractive index of bulk solution and non-specific adsorption of bovine serum albumin is provided. Further investigation of the sensor capabilities involved specific detection of human red blood cells and leukemia markers. Red blood cell detection was based on ABO blood grouping and included the estimation of limit of detection and signal-to-noise ratio for single cell detection. Finally, a clinically relevant problem of B-cell leukemia marker detection was targeted. The sensor demonstrated the ability to detect the relative abundance of similar proteins (immunoglobulin kappa and lambda) in a complex fluid (human serum). In addition, an experimental study on the optimization of the sensor for sensitivity was conducted.

Стилі APA, Harvard, Vancouver, ISO та ін.

10

Nemzer, Louis R. "Oxidoreductase Immobilization in Reprecipitated Polyaniline Nanostructures for Optical Biosensing Applications." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1265751296.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

11

Bertó, Roselló Francisco. "Numerical modelling of nanoporous anodic alumina photonic structures for optical biosensing." Doctoral thesis, Universitat Rovira i Virgili, 2018. http://hdl.handle.net/10803/665620.

Повний текст джерела

Анотація:

Alguns materials mostren propietats físiques, òptiques i químiques particulars en la nanoescala. La nanotecnologia permet al científic millorar les seves propietats modificant l'estructura de la matèria en aquest nivell i aprofitar-les per al desenvolupament de nous dispositius i aplicacions. Particularment important és la investigació en biosensors per tal d'obtenir dispositius més sensibles i fiables, per a desplegar-los en la societat en forma de sistemes de diagnòstic rendibles i fiables. La fabricació d'aquests dispositius en alguns casos implica la manipulació de la llum en aquests materials en la nanoescala, per a això, cal tenir un coneixement profund del comportament òptic de l'estructura. En aquest sentit, l'elecció del material apropiat és decisiva en el desenvolupament de dispositius biosensors. La alúmina anòdica nanoporosa (AAN) és un material porós autoordenat les propietats òptiques del qual en el visible, la seva gran adaptabilitat de l'estructura, la seva capacitat per actuar com a suport o bastida d'objectes petits i la seva estabilitat en condicions biològiques, el fan especialment apropiat com a plataforma per el desenvolupament de biosensors òptics. Els estudis teòrics sobre les propietats òptiques de la AAN són un camp fonamental d'investigació. El modelatge numèric d'aquestes propietats permet comprendre la seva relació amb les característiques estructurals de la AAN, proporcionant un marc conceptual per a l'anàlisi del seu comportament òptic. En aquesta tesi, hem analitzat la idoneïtat i desenvolupat diversos models predictius per a les propietats òptiques de l’AAN, vàlids en una àmplia gamma de característiques geomètriques. Posteriorment, el nostre model de simulació es va aplicar per estudiar la idoneïtat de dos tipus d'estructures d’AAN revestides d'or com a plataforma per al desenvolupament de biosensors plasmònics per reflectometria. Finalment, s'ha realitzat un estudi teòric del comportament òptic mitjançant modelatge numèric d'estructures basades en AAN amb un gradient en l'índex de refracció
Algunos materiales muestran propiedades físicas, ópticas y químicas particulares a nanoescala. La nanotecnología permite al científico mejorar sus propiedades modificando la estructura de la materia en este nivel y aprovecharlas para el desarrollo de nuevos dispositivos y aplicaciones. Particularmente importante es la investigación en biosensores con el fin de obtener dispositivos más sensibles y confiables para desplegarlos en la sociedad en forma de sistemas de diagnóstico rentables y confiables. La fabricación de tales dispositivos en algunos casos implica la manipulación de la luz en estos materiales en la nanoescala, para lo cual, es necesario tener un conocimiento profundo del comportamiento óptico de la estructura. En este sentido, la elección del material apropiado es decisiva en el desarrollo de dispositivos biosensores. La alúmina anódica nanoporosa (AAN) es un material poroso autoordenado cuyas propiedades ópticas en lo visible, su gran adaptabilidad de la estructura, su capacidad para actuar como soporte o andamio de objetos pequeños y su estabilidad en condiciones biológicas lo hacen especialmente apropiado como plataforma para el desarrollo de biosensores ópticos. Los estudios teóricos sobre las propiedades ópticas de la AAN son un campo fundamental de investigación. El modelado numérico de estas propiedades permite comprender su relación con las características estructurales de la AAN, proporcionando un marco conceptual para el análisis de su comportamiento óptico. En esta tesis, hemos analizado la idoneidad y desarrollado varios modelos predictivos para las propiedades ópticas de la AAN válidos en una amplia gama de características geométricas. Posteriormente, nuestro modelo de simulación se aplicó para estudiar la idoneidad de dos tipos de estructuras AAN revestidas de oro como plataforma para el desarrollo de biosensores plasmónicos por reflectometría. Finalmente, se ha realizado un estudio teórico del comportamiento óptico mediante modelado numérico de estructuras basadas en AAN con un gradiente en el índice de refracción.
Some materials shown particular physical, optical and chemical properties at the nanoscale. The nanotechnology permits to scientist enhance their properties modifying the matter structure at this level and take advantage of them for the development of new devices and applications. Particularly important is the research in biosensing in order to obtain more sensitive and reliable devices with a view for their deployment to society in the form of cost-effective and reliable diagnostic systems. The manufacturing of such devices in some cases implies the manipulation of the light in these materials at the nanoscale, for which it implies to have a deep knowledge of the optical behaviour of the structure. In this sense, the election of the appropriate material is decisive in the development of biosensing devices. Nanoporous anodic alumina (NAA) is a self-ordered porous material which their optical properties in the visible, their great tunability of the structure, their ability to act as a holder or scaffold of small objects and their stability under biological conditions make it especially appropriate as a platform for the development of optical biosensors. Theoretical studies on the NAA optical properties is a fundamental field of research. The numerical modelling of these properties permits to understand their relationship with the structural features of the NAA, providing a conceptual framework for the analysis of their optical behaviour. In this thesis, we have analyzed the suitability and developed several predictive models for the optical properties of the NAA valid in a wide range of geometrical characteristics. Subsequently our simulation model has been applied to study the suitability of two types of gold-coated NAA structures as a platform for reflectometric-based plasmonic biosensors. Finally, a theoretical study of the optical behaviour by means of numerical modelling of gradient-index NAA (NAA-GI) based structures has been performed.

Стилі APA, Harvard, Vancouver, ISO та ін.

12

Martínez, Pérez Paula. "Development and Optimization of Experimental Biosensing Protocols Using Porous Optical Transducers." Doctoral thesis, Universitat Politècnica de València, 2021. http://hdl.handle.net/10251/172541.

Повний текст джерела

Анотація:

[ES] Los biosensores son dispositivos analíticos con aplicabilidad en diferentes campos y con numerosas ventajas frente a otros métodos analíticos convencionales, como son el uso de pequeños volúmenes de muestra y reactivos, su sensibilidad y su rápida respuesta, sin necesidad de pretratamiento de la muestra, equipos caros o personal especializado. Sin embargo, se trata de un campo de investigación relativamente nuevo en el que todavía queda mucho camino por andar. Esta Tesis doctoral pretende aportar un granito de arena a este campo de conocimiento mediante el estudio del potencial de diferentes materiales porosos como transductores para el desarrollo de biosensores ópticos con respuesta en tiempo real y sin marcajes. Los materiales propuestos van desde aquellos artificialmente sintetizados, como silicio poroso (SiP), nanofibras (NFs) poliméricas o membranas poliméricas comerciales, hasta materiales naturales con propiedades fotónicas que todavía no habían sido explotadas para el sensado, como son los exoesqueletos de biosílice de diatomeas. Todos ellos tienen en común la simplicidad en su obtención, evitando costosos y laboriosos procesos de nanofabricación. Para su estudio, se analizará su respuesta óptica y, en aquellos casos en los que ésta permita llevar a cabo experimentos de detección, se desarrollarán estrategias para su biofuncionalización y su implementación en experimentos de biosensado. En el caso del SiP y las NFs se han optimizado los parámetros de fabricación para obtener una respuesta óptica adecuada que permita su interrogación. A continuación, se ha llevado a cabo su biofuncionalización empleando métodos covalentes y no covalentes, así como diferentes bioreceptores (aptámeros de ADN y anticuerpos) para estudiar su potencial y sus limitaciones como biosensores. En el caso de las membranas comerciales y el exoesqueleto de sílice de diatomeas, se ha caracterizado su respuesta óptica y se han llevado a cabo experimentos de sensado de índice de refracción para estudiar su sensibilidad. Así mismo, se ha desarrollado un método de funcionalización de la superficie del exoesqueleto de diatomeas basado en el uso de polielectrolitos catiónicos. Como resultado, se ha demostrado el potencial tanto de NFs para el desarrollo de biosensores, como el de membranas comerciales para sensores cuya aplicación no requiera una elevada sensibilidad pero sí un bajo coste. Además, se ha puesto de manifiesto el gran potencial del exoesqueleto de diatomeas para el desarrollo de sensores basados en su respuesta óptica. Por el contrario, las limitaciones encontradas en el desarrollo de biosensores basados en SiP han evidenciado la necesidad de un estudio riguroso y la optimización de la estructura de materiales porosos previamente a ser usados en (bio)sensado.
[CA] Els biosensors són dispositius analítics amb aplicabilitat en diferents camps i amb nombrosos avantatges enfront d'altres mètodes analítics convencionals, com són l'ús de xicotets volums de mostra i reactius, la seua sensibilitat i la seua ràpida resposta, sense necessitat de pretractament de la mostra, equips cars o personal especialitzat. No obstant això, es tracta d'un camp d'investigació relativament nou en el qual encara queda molt camí per fer. Aquesta Tesi doctoral pretén aportar el seu òbol a aquest camp de coneixement mitjançant l'estudi del potencial de diferents materials porosos com a transductors per al desenvolupament de biosensors òptics amb resposta en temps real i sense marcatges. Els materials proposats van des d'aquells artificialment sintetitzats, com a silici porós (SiP), nanofibras (NFs) polimèriques o membranes polimèriques comercials, fins a materials naturals amb propietats fotòniques que encara no havien sigut explotades per al sensat, com són els exoesquelets de biosílice de diatomees. Tots ells tenen en comú la simplicitat en la seua obtenció, evitant costosos i laboriosos processos de nanofabricació. Per al seu estudi, s'analitzarà la seua resposta òptica i, en aquells casos en els quals aquesta permeta dur a terme experiments de detecció, es desenvoluparan estratègies per a la seua biofuncionalizació i la seua implementació en experiments de biosensat. En el cas del SiP i les NFs s'han optimitzat els paràmetres de fabricació per a obtenir una resposta òptica adequada que permeta la seua interrogació. A continuació, s'ha dut a terme la seua biofuncionalizació emprant mètodes covalents i no covalents, així com diferents bioreceptors (aptàmers d'ADN i anticossos) per a estudiar el seu potencial i les seues limitacions com a biosensors. En el cas de les membranes comercials i l'exoesquelet de sílice de diatomees, s'ha caracteritzat la seua resposta òptica i s'han dut a terme experiments de sensat d'índex de refracció per a estudiar la seua sensibilitat. Així mateix, s'ha desenvolupat un mètode de funcionalizació de la superfície de l'exoesquelet de diatomees basat en l'ús de polielectròlits catiònics. Com a resultat, s'ha demostrat el potencial tant de NFs per al desenvolupament de biosensors, com el de membranes comercials per a sensors amb una aplicació que no requerisca una elevada sensibilitat però sí un baix cost. A més, s'ha posat de manifest el gran potencial de l'exoesquelet de diatomees per al desenvolupament de sensors basats en la seua resposta òptica. Per contra, les limitacions trobades en el desenvolupament de biosensors basats en SiP han evidenciat la necessitat d'un estudi rigorós i l'optimització de l'estructura dels materials porosos prèviament a ser usats en (bio)sensat.
[EN] Biosensors are analytical devices with application in diverse fields and with several advantages relative to other conventional methods, such as the use of small volumes of sample and reagents, their sensitivity and their fast response, without the need of the sample pretreatment, expensive equipments or specialised technicians. Nevertheless, this is a relatively new research field in which there is a long way to go yet. This doctoral Thesis aims at doing its bit to this field of knowledge by studying the potential of different porous materials as transducers for the development of real-time and label-free optical biosensors. The proposed materials range from those artificially synthesised, such as porous silicon (pSi), polymeric nanofibres (NFs) or commercial polymeric membranes, to natural materials with photonic properties that had not been exploited for sensing yet, such as biosilica exoskeletons of diatoms. All of them have in common its simple production, avoiding expensive and laborious nanofabrication processes. For their study, their optical response will be analysed and, in those cases in which such optical response allows performing detection experiments, strategies for their biofunctionalisation and their implementation in biosensing experiments will be developed as well. Regarding pSi and NFs, the fabrication parameters were optimised to get a suitable optical response for their interrogation. Afterwards, their surface functionalisation was carried out by covalent and non-covalent methods, as well as different bioreceptors (DNA aptamers and antibodies), to study their potential and their constraints as biosensors. Concerning commercial membranes and the biosilica exoskeleton of diatoms, their optical response was characterised and refractive index sensing experiments were carried out to study their sensitivity. Additionally, a biofunctionalisation method for the surface of the diatoms exoskeleton was developed based on the use of cationic polyelectrolytes. As a result, it was demonstrated the potential of NFs for the development of biosensors, as well as the potential of commercial membranes for developing sensors for an application that does not require a high sensitivity but a low cost. Furthermore, the great potential of biosilica exoskeleton of diatoms for the development of sensors based on their optical response has been revealed. By contrast, the constraints found in the development of pSi illustrate the importance of an accurate study and optimisation of porous materials structure before using them for (bio)sensing.
Martínez Pérez, P. (2021). Development and Optimization of Experimental Biosensing Protocols Using Porous Optical Transducers [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/172541
TESIS

Стилі APA, Harvard, Vancouver, ISO та ін.

13

Badmos, Abdulyezir. "Advanced optical fibre gratings for nano-structural characterisation and biosensing applications." Thesis, Aston University, 2017. http://publications.aston.ac.uk/30869/.

Повний текст джерела

Анотація:

This thesis presents detailed investigation on the fabrication, spectral characterisation and applications of UV-inscribed optical fibre gratings devices. Of prominent significance is the characterisation of the optical fibre gratings devices with nanoparticles and biological recognition elements for novel developments in the field of optical biosensing. A major contribution detailed in this thesis is the systematic study on fabrication, spectral characterisation and applications of different UV-inscribed in-fibre gratings. Specifically, uniform and apodized Fibre Bragg gratings (FBGs), normal and dual-peak long period fibre gratings (LPFGs), small-angle tilted fibre gratings (S-TFGs) and excessively tilted fibre gratings (Ex-TFGs) are presented. The holographic, phase-mask scanning and point-by-point methods are employed to fabricate these advanced optical fibre gratings using 244nm frequency-doubled Ar+ laser. Particular emphasis is laid on fabrication of dual-peak LPFGs in SMF-28 and thin-cladding single mode fibres of grating periods 140μm and 300μm respectively. Also, Ex-TFGs of different tilt angles are inscribed in single mode fibres using amplitude masks of different periods: 5.0μm, 6.6μm and 25μm. Another important contribution from this study is the nano-structural characterisation of the in-fibre gratings with nanoparticles such as carbon nanotubes (CNT), zinc oxide (ZnO) and gold nanoparticles for power demodulation, sensitivity enhancement and polarisation dependent SPR excitation respectively. Refractive index (RI) sensors based on 81° Ex-TFGs with carbon nanotube (CNT) overlay deposition have been investigated. The CNT, a dark material, with high absorption of light and high RI is responsible for the power demodulation of the attenuation band while the 81°-TFG induces the wavelength shift as the surrounding medium RI changes. Results show high sensitivities of 557.29 nm/RIU and 95.54 dB/RIU for the wavelength shift and power demodulation respectively. Also, nano-deposition of zinc oxide (ZnO) on Ex-TFGs inscribed in two different fibre types has been investigated using dissimilar morphologies (direct ZnO overlay and PSZnO overlay) for enhanced RI sensing. Significant improvement in sensitivity of ~ 21% (~ 522 nm/RIU) is obtained. The polarisation dependence of Au-coated S-TFGs on excitation of surface plasmon resonance (SPR) has also been investigated. Finally, the in-fibre gratings are surface-functionalized with bioreceptor elements such as enzymes (glucose oxidase) and antibody/antigen (Trx, IL-6). Enzyme functionalized biosensor based on dual-peak LPFG has been investigated for sugar concentration level and specific glucose detection and high sensitivities of ~4.67 nm/% and 12.21 ± 0.19 nm/ (mg/ml) are obtained respectively. Also, fibre optic biosensors based on antibodyfunctionalized 81º-TFGs have been presented for label-free specific recognition of interleukin-6 (IL-6) and thioredoxin (Trx) proteins. High saturation values (∧λ max ) of 35.05nm and 33.19nm are obtained respectively. The specificity validation of the biosensors in the presence of other interfering proteins is investigated using human plasma and results show high specificity.

Стилі APA, Harvard, Vancouver, ISO та ін.

14

Yavas, Ozlem. "On-chip biosensing platforms based on gold and silicon optical nano-resonators." Doctoral thesis, Universitat Politècnica de Catalunya, 2019. http://hdl.handle.net/10803/667307.

Повний текст джерела

Анотація:

Point-of-care (POC) devices are compact, mobile and fast detection platforms expected to advance early diagnosis, treatment monitoring and personalized healthcare, and revolutionize today’s healthcare system, especially in remote areas. The need for POC devices strongly drives the development of novel biosensor technology. Building a small, fast, simple, and sensitive platform for biomolecule detection is a challenge that relies on the integration of multiple fields of expertise and engineering. Optical nanoresonators have shown great promise as label-free biosensors because of direct light coupling and sub-wavelength sensing modes. Metallic nanoresonators with localized surface plasmon resonances (LSPR) are already well studied and were proven a solid alternative to the commercialized surface plasmon resonance (SPR) sensors. More recently, dielectric nanoresonators have also gained traction due to the reduced losses and the ability to manipulate both the electric and magnetic components of the incident light. In this thesis, we advance the field of biosensing and use optical nanoresonators as operative platforms relevant for disease diagnosis and treatment monitoring. By combining different optimized optical nanoresonators, both metallic and dielectric, with state-of-the-art microfluidics and surface chemistry, we have developed and tested several detection platforms. We first focused on developing a microfluidic lab-on-chip device for multiplexed biosensing utilizing the LSPR of gold nanoresonator arrays. By simultaneously tracking the extinction of 32 sensor arrays, we demonstrated multiplexed quantitative detection of four breast cancer markers in human serum. We showed that with well-optimized immunoassays, a low limit of detection (LOD) can be reached, paving the way towards clinically-relevant POC devices. Additionally, we implemented silicon nanoresonators supporting Mie resonances into functional and clinically-relevant applications. By integrating several arrays of Si nanoresonators with state-of-the-art microfluidics, we demonstrated their ability to detect cancer markers in human serum with high sensitivity and high specificity. Furthermore, we showed that the fabrication of Si nanoresonator array using low cost and scalable projection lithography leads to sufficiently low limits of detection, while enabling cheaper and faster sensor production for future POC applications. We also investigated the respective role of electric and magnetic dipole resonances and showed that they are associated with two different transduction mechanisms: resonance redshift and extinction decrease. Our work advances the development of future point-of-care sensing platforms for fast and low cost health monitoring at the molecular scale.
La instrumentación Point-of-care (POC) es compacta, móvil y permite una detección rápida, razón por la que se prevé que sean de gran ayuda en áreas como el diagnostico precoz, la monitorización de tratamientos y la medicina personalizada, revolucionando los modelos sanitarios, especialmente en las zonas de difícil acceso y con menos recursos. La necesidad de este tipo de dispositivos impulsa el desarrollo de novedosas tecnologías en el campo de los bio-sensores. Diseñar equipos para la detección de bio-moléculas que sean rápidos, pequeños y sencillos es un reto que requiere la integración de múltiples campos de la ciencia y la ingeniería. Los nano-resonadores ópticos muestran un gran potencial como bio-sensores sin necesidad de marcaje, gracias a su capacidad de acoplase directamente con la luz en modos menores que la longitud de onda. Los nano-resonadores metálicos basados en resonancias plasmónicas superficiales localizadas (LSPR) han sido estudiados y han demostrado ser una firme alternativa a los ya comerciales basados en resonancias plasmónicas superficiales (SPR). Los nano-resonadores dieléctricos han sido recientemente objeto de atención debido a sus bajas perdidas y la capacidad de manipular los componentes eléctricos y magnéticos de la luz. En esta tesis presentamos avances en el campo de la bio-detección y en el uso de los nano-resonadores ópticos como potenciales herramientas para la detección de enfermedades y monitorización de los tratamientos. Hemos desarrollado y evaluado distintas plataformas de detección combinando los nano-resonadores ópticos, tanto metálicos como dieléctricos, con las más avanzadas técnicas de microfluídica y química de superficies. En primer lugar, nos centramos en el desarrollo de un dispositivo microfluídico basado en sensores LSPR de oro que permite multiplexar 32 canales. Los 32 sensores se monitorizan en tiempo real para demostrar la cuantificación de 4 marcadores de cáncer de mama en suero sanguíneo humano. Demostramos que mediante la optimización de los ensayos se pueden alcanzar bajos límites de detección (LOD), lo que allana el camino hacia dispositivos POC de uso clínico. Por otro lado, hemos utilizado los nano-resonadores de silicio integrados con la microfluídica para también detectar marcadores de cáncer en suero. Estos sensores, cuyo principio de funcionamiento se basa en resonancias de MIE, han demostrado ser una alternativa razonable a los sensores de oro. Además, demostramos que un proceso de fabricación de nano-resonadores de silicio rápido, escalable y de bajo coste da lugar a límites de detección suficientes para la producción de futuras POC. También realizamos un minucioso estudio del rol de las resonancias eléctricas y magnéticas en dichos sensores y su relación con el desplazamiento y el cambio magnitud de la resonancia del sensor global. Nuestro trabajo es un avance en el desarrollo de futuros instrumentos POC rápidos y baratos en el ámbito de la salud a escala molecular.

Стилі APA, Harvard, Vancouver, ISO та ін.

15

Bailey, J. "Multiscale optical patterning : using micro and nano periodic structures to create novel optical devices with applications to biosensing." Thesis, University College London (University of London), 2016. http://discovery.ucl.ac.uk/1519804/.

Повний текст джерела

Анотація:

Patterning, the utilisation and manipulation of geometric properties, is important both for the rational design of technological devices and also to the understanding of many natural phenomena. In this thesis I examine the way in which micro and nano patterning can alter optical properties across a large range of wavelength scales and how these novel phenomena can be utilised. Micro patterned electrodes can tune the geometry of radio frequency electric fields to generate dielectrophoretic microfluidic devices. These devices use the dielectrophoretic force to sort, position and characterise the properties of micro and nano particles. I develop a new image processing algorithm that radically improves experimental efficiency allowing for real-time supervisor free dielectrophoretic characterisation of nanoparticles. Metamaterials are composite structures that have repeating units that are much smaller than the wavelength of radiation they are designed to work with. The optical properties of the materials are derived from these units rather than the bulk characteristics of the materials they are composed of. I demonstrate the development of novel THz metamaterial absorber devices. These devices provide a means to design and control the absorption of THz radiation, modulating bandwidth, polarization dependence and frequency in a form that is readily integrable with other standard fabrication processes. Finally by periodically patterning materials on the nanometer scale I demonstrate the development of novel photonic crystal devices and complementary optical components. In these devices the periodicity of the electromagnetic wave is modulated by the periodicity of the structures themselves resulting in band gaps and resonances analogous to the band gaps and defect states found commonly in semi-conductor physics. I demonstrate the theory, fabrication and measurement of these devices using novel broadband supercontinuum sources and propose a future application for biosensing. Further topics covered in the appendix include the development of a spin out technology, a $100 open source atomic force microscope developed while spending time in China. Finally I examine the role of patterning for optimising the performance of nanomechanical cantilever biosensors, and show how geometrical effects on the microscopic scale are crucial to understanding the workings of the vancomycin family of antibiotics, as screened using microcantilevers. Portions of this report are edited extracts from published articles resulting from this work, a full list of which is given in Appendix A.

Стилі APA, Harvard, Vancouver, ISO та ін.

16

Montali, Laura <1994&gt. "Smartphone-based analytical devices with optical detection for on-site biosensing: environmental, food and forensic applications." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amsdottorato.unibo.it/10021/1/TESI_LAURA_MONTALI_SUBMISSION_20_01_22.pdf.

Повний текст джерела

Анотація:

There has been an increasing demand for fast and easy monitoring technologies designed to respond to different analytes. The standard analytical techniques offer accurate and precise results; however, they require clean samples, sophisticated equipment and skilled personnel. For these reasons, they are not suitable for on site, real-time, cost-effective routine monitoring. Biosensors are analytical devices integrating a biological recognition element and a transducer element able to convert the biological response into an easily measurable analytical signal. These tools can easily quantify an analyte or a class of analytes of interest even in a complex matrix, like clinical or environmental samples, thanks to the specificity of the biological components and can be easily implemented in portable devices. The activity carried out during my PhD was mainly focused on the development of different portable paper-based biosensors for multianalyte detection and their implementation into portable analytical devices for point-of-care and point-of-need applications. In particular, enzymes and cells (bacteria and mammalian cell) have been exploited as biorecognition elements, in some cases even by coupling different elements in the same biosensor to increase its robustness. The final goal of biosensors developed was the application in the environmental and forensic fields, since the target analytes are organophosphorus pesticides, heavy metals and molecules with androgenic activity, including new drugs or endocrine disrupting chemicals. Moreover, different optical detection principles (chemiluminescence, bioluminescence, colorimetry) have been exploited and coupled to create an orthogonal detection, which provides more accurate results. Different portable detectors, such as coupled-charged device, smartphone cameras and silicon photomultiplier, and also benchtop laboratory instruments have been used to validate and support the developed biosensors. Several paper-based platforms have been designed and implemented with adaptors and devices fabricated using a dual-extrusion 3D printer to better adapt to the type of assay, reagents, samples and detection method.

Стилі APA, Harvard, Vancouver, ISO та ін.

17

Wang, M. (Meng). "Polymer integrated Young interferometers for label-free biosensing applications." Doctoral thesis, Oulun yliopisto, 2012. http://urn.fi/urn:isbn:9789514299643.

Повний текст джерела

Анотація:

Abstract Integrated optical (IO) sensor allowing sensitive, label-free, real-time and multi-parameter monitoring of bio-molecular interactions are conventionally fabricated with inorganic dielectrics inherited from CMOS manufacturing technology. Polymers as complement materials to inorganic dielectrics are becoming to have an increasing market share for IO circuits in optical communications networks owing to its good optical properties, versatile processibility and low cost. This work aims at developing disposable low-cost biosensors based mainly on polymeric materials, with a performance comparable to inorganic-dielectric based IO biosensors. This thesis describes the development of polymer IO biosensors based on the Young interferometer (YI) transducer platform for ambient noise compensation and a complete periodic intensity fringe pattern. Three different waveguide configurations were utilized, taking into consideration operational simplicity, fabrication simplicity and enhanced sensitivity. Among the developed polymer biosensors, an unconventional interferometer structure: a vertically placed dual-slab waveguide interferometer and an inverted rib waveguide configuration were employed. To enhance the sensitivity of the waveguides, deposition of Ta2O5 high index coating was performed on the rib waveguide configuration. Along with the development of polymer biosensors based on the inverted-rib waveguide configuration, a fabrication process was also developed featuring UV-imprinting and spin coating. The simple two-step fabrication process demonstrated using a polymer mold is potentially transferable to the roll-to-roll manufacture process. Calibration of the developed sensors was performed by homogeneous refractive index (RI) sensing with glucose de-ionized water solutions. By investigating an antibody – antigen binding interaction involving C-reactive protein and its conjugates, this thesis confirmed the applicability of the developed sensors to specific molecule detection. Moreover, to establish the influence of water molecular absorption on measurement stability, an evaluation was carried out on the polymeric waveguide. Finally, the thesis presented a comparison between the developed sensors, exploring their sensitivities, stabilities, limits of detection (LODs) and other aspects related to operation and fabrication. The results indicated that the Ta2O5-coated polymer waveguide sensor had a high sensing capability. In homogeneous RI sensing, the achieved detection limits were 9×10-7 RIU (refractive index unit), i.e., three times the noise level, and 270 fg/mm2 for surface mass density
Tiivistelmä Integroidulla optiikalla toteutetut anturit mahdollistavat biomolekulaarisen vuorovaikutuksen tutkimisen käyttäen herkkiä moniparametrisia ja merkkiaineettomia menetelmiä. Näiden bioantureiden valmistukseen käytetään tavallisesti CMOS-teknologian piiristä tuttuja epäorgaanisia puolijohteita ja eristemateriaaleja. Viime aikoina on kuitenkin polymeeristen materiaalien käyttöä integroidussa optiikassa tutkittu merkittävästi johtuen polymeerien hyvistä optisista ominaisuuksista, monipuolisesta työstettävyydestä ja edullisista kustannuksista. Tämän työn tarkoituksena on kehittää edullisia, kertakäyttöisiä, pääasiallisesti polymeerisistä materiaaleista valmistettuja bioantureita, jotka vastaavat suorituskyvyltään epäorgaanisista materiaaleista valmistettuja integroidun optiikan antureita. Tässä työssä kehitetyt polymeeriset integroidun optiikan bioanturit perustuvat Youngin interferometriin mahdollistaen ympäristökohinan kompensoinnin ja ne tuottavat pintavuorovaikutusten tutkimiseen jaksoittaisen interferenssikuvion. Työssä hyödynnettiin kolmea erilaista valokanavarakennetta huomioiden niiden käytön helppous, valmistuksen yksinkertaisuus ja mittausherkkyys. Yksi kehitetyistä polymeerisistä bioantureista koostui päällekkäisistä kerrostetuista polymeerikerroksista. Toisen tutkitun rakenteen toiminta puolestaan perustui käänteiseen harjannevalokanavaan. Mittausherkkyyttä parannettiin pinnoittamalla polymeerirakenne Ta2O5-pinnoitteella. Näin muodostui kerrostettu komposiittivalokanava, joka oli tässä työssä tutkittu kolmas sensorirakenne. Itse bioanturien lisäksi kehitettiin myös valmistusprosessi, jossa hyödynnettiin UV-painatusta ja nestefaasipinnoitusta. Tässä työssä havaittiin lisäksi, että kehitetty yksinkertainen valmistusmenetelmä on paitsi toimiva, myös mahdollisesti siirrettävissä rullalta rullalle valmistus- ja tuotantoteknologiaan. Kehitettyjen anturien kalibrointi suoritettiin homogeenisella taitekerroinmittauksella käyttäen liuoksia, jotka valmistettiin glukoosista ja deionisoidusta vedestä. Kehitettyjen anturien soveltuvuus spesifien molekyylien tunnistamista varten todennettiin tutkimalla vasta-aineiden ja antigeenien sitoutumisreaktioita ja vuorovaikutusta C-reaktiivisella proteiinilla ja sen konjugaateilla. Lisäksi työssä tutkittiin veden absorption vaikutusta mittauksen stabiilisuuteen. Tutkimuksessa suoritettiin vertailu kehitettyjen anturien ja niiden ominaisuuksien välillä kiinnittäen huomiota mittausherkkyyteen, stabiilisuuteen, määritys- ja toteamisrajoihin ja muihin anturien valmistukseen sekä käyttöön liittyviin keskeisiin piirteisiin. Tulokset osoittavat, että Ta2O5-pinnoitetun polymeerivalokanavan mittausherkkyys oli suurin vertailluista rakenteista. Homogeenisessä taitekerroinmittauksessa saavutettu määritys- ja toteamisraja oli 9×10-7 taitekerroinyksikköä (RIU). Pintamassatiheysmittauksessa saavuttu tulos oli 270 fg/mm2

Стилі APA, Harvard, Vancouver, ISO та ін.

18

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

Повний текст джерела

Анотація:

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

Стилі APA, Harvard, Vancouver, ISO та ін.

19

Romero-García, Sebastián [Verfasser], Jeremy [Akademischer Betreuer] Witzens, and Iñigo [Akademischer Betreuer] Molina-Fernández. "Integrated photonics for high speed optical interconnects and biosensing applications / Sebastián Romero-García ; Jeremy Witzens, Iñigo Molina-Fernández." Aachen : Universitätsbibliothek der RWTH Aachen, 2016. http://d-nb.info/113040305X/34.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

20

Nicolini, Ariana Marie, and Ariana Marie Nicolini. "Single-Step, Optical Biosensors for the Rapid and Sensitive Detection of Bacterial and Viral Pathogens." Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/623158.

Повний текст джерела

Анотація:

This dissertation discusses the development of inexpensive, easy-to-use, and field-deployable diagnostic techniques and devices for the early detection of various pathogens, commonly found in clinical samples and contaminated food and water. Infectious diseases account for about 90% of world health problems, killing approximately 14 million people annually, the majority of which reside in developing countries. In 2012, the World Health Organization (WHO) published data on the top 10 causes of death across the globe. Although communicable disease is a prevalent cause of fatality, both low-income and high-income countries, pathogen species and transmission are very different. Nearly 60% of deaths in developing countries are caused by food, water, air or blood-borne pathogens. The most prevalent illnesses are diarrheal disease, malaria, and HIV/AIDS. By contrast, the leading causes of death in developed countries (heart disease, cancer, and stroke) are not communicable and are often preventable. However, there is an increasing need for the development of rapid and accurate methods for pathogen identification in clinical samples, due to the growing prevalence of antibiotic-resistant strains. Incorrect, or unneeded antibiotic therapies result in the evolution of extremely aggressive nosocomial (hospital-acquired) infections, such as methicillin- (MRSA) and vancomycin-resistant Staphylococcus aureus (VRSA). The implementation of rapid, easy to use and cost-effective diagnostics will reduce the frequency of pathogen-related deaths in underdeveloped countries, and improve targeted antibiotic treatment in hospital settings, thus decreasing the potential development of more treatment-resistant "super bugs". This research includes novel techniques utilizing two major sensing modalities: serological (i.e. immunological), and nucleic acid amplification testing (NAATs). We first developed a highly sensitive (limit-of-detection = 100 CFU mL-1) particle immunoassay that takes advantage of elastic and inelastic light scatter phenomena, for optical detection of target antigens. This assay is performed upon a unique nanofibrous substrate that promotes multiplexing on a user-friendly platform. We then developed a novel technique, termed emulsion loop-mediated isothermal amplification (eLAMP), in which the target amplicon is detected in real-time, again utilizing light scattering detection and quantification. Both techniques require no sample pre-treatments, and can be combined with smartphone imaging for detection of targets in under 15 minutes. These methods have the potential to improve the speed and sensitivity of early pathogenic identification, thus leading to a reduction in preventative deaths and a decrease in global economic costs associated with infectious disease in clinical and other settings.

Стилі APA, Harvard, Vancouver, ISO та ін.

21

Doherty, Brenda [Verfasser], Markus A. [Gutachter] Schmidt, Rachel [Gutachter] Grange, and Isabelle Philippa [Gutachter] Staude. "Plasmonic microstructured optical fibres : an efficient platform towards biosensing / Brenda Doherty ; Gutachter: Markus A. Schmidt, Rachel Grange, Isabelle Philippa Staude." Jena : Friedrich-Schiller-Universität Jena, 2020. http://d-nb.info/121099853X/34.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

22

Rye, Jan-Michael. "Spatial Modulation Spectroscopy Of Single Nano-Objects In A Liquid Environment For Biosensing Applications." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1053/document.

Повний текст джерела

Анотація:

Le développement de méthodes rapides, précises et ultra-sensibles pour la détection d'analytes cibles en solution est crucial pour la recherche et les applications potentielles en médecine ou biologie moléculaire. Une approche très prometteuse consiste à développer des nano-capteurs à partir de nano-objets métalliques (NOM) qui présentent une résonance d'extinction dans leur réponse optique. Cette résonance nommée résonance de plasmon de surface localisée (RPSL) peut être ajustée spectralement en jouant sur la nature, la morphologie et l'environnement du NOM. Mesurer des modifications sur la RPSL de nano-objets individuels en présence d'analytes cibles doit permettre de s'affranchir des effets de moyennes dans les mesures d'ensemble. De plus, cela ouvre la voie vers le développement d'échantillons micrométriques pour des tests multicibles sans étiquette (« label-free »).Dans ce travail on a développé un nouveau dispositif expérimental basé sur la technique de spectroscopie à modulation spatiale (SMS) permettant de sonder la réponse optique de NOM individuels en milieu liquide. En parallèle des méthodes de synthèse ont été mises au point pour obtenir des échantillons sondes stables permettant des mesures sur NOM unique, en particulier sur des bipyramides d'or qui présentent de nombreuses qualités intrinsèques faisant d'elles de bonnes candidates pour le « bio-sensing ».Des mesures ont été réalisées dans des environnements d'indice variable et les changements détectés sont en bon accord avec les simulations théoriques. De plus, de nombreuses études ont été réalisées pour comprendre l'influence des nombreux paramètres agissant sur la réponse optique des systèmes étudiés
Advances in the development of rapid, accurate and highly sensitive methods for detecting target analytes in solution will provide crucial tools for research and applications in medicine and molecular biology. One of the currently most promising approaches is the development of nanosensors based on the localized surface plasmon resonance (LSPR) of noble metal nano-objects (MNOs), which is an optical response that depends on their size, shape, composition and local environment. The ability to measure the modification of the reponse of a single MNO in the presence of a target analyte would allow each object to act as an independent probe with increased sensitivity as the signal would be isolated from the averaging effects of ensemble measurements. Furthermore it would allow the development of micrometric, functionalized multiprobe samples for multitarget label-free assays.In this work, a novel experimental setup based on the spatial modulation spectroscopy (SMS) technique has been developed to measure the optical response of individual nano-objects in a liquid environment. In parallel, a new technique has also been developed to elaborate stable probes for measurements with the new setup, with a focus on gold bipyramids due to numerous qualities that make them excellent candidates for biosensing probes. The setup has been used to measure the response of individual objects in environments of different real refractive indices and the detected changes have been shown to be in good agreement with theoretical calculations. Numerical studies have also been performed to investigate the influence on the optical response of numerous factors encountered in the studied systems

Стилі APA, Harvard, Vancouver, ISO та ін.

23

Gylfason, Kristinn Björgvin. "Integrated Optical Slot-Waveguide Ring Resonator Sensor Arrays for Lab-on-Chip Applications." Doctoral thesis, KTH, Mikrosystemteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-12214.

Повний текст джерела

Анотація:

This thesis treats the development of an integrated optical sensor array. The sensors are slot-waveguide ring resonators, integrated with on-chip surface grating couplers and light splitters, for alignment tolerant, real-time, refractive index sensing, and label-free biosensing. The work includes: the design of components and system layouts, the development of fabrication methods, the fabrication of sensor chips, the characterization of the chips, and the development of physical system models for accurate extraction of resonance wavelengths in measured spectra. The main scientific achievements include: The evaluation of a novel type of nano-structured optical waveguide for biochemical sensing. The realization of an array of such slot-waveguide sensors, integrated with microfluidic sample handling, for multiplex assays. The first study of the thermal behavior of slot-waveguide sensors and the discovery of unique temperature compensation capabilities. From an application perspective, the use of alignment tolerant surface gratings to couple light into the optical chip enables quick replacement of cartridges in the read-out instrument. Furthermore, the fabrication sequence avoids polishing of individual chips, and thus ensures that the cost benefits of silicon batch micro-fabrication can be leveraged in mass production. The high sensitivity of the slot waveguide resonators, combined with on-chip referencing and physical modeling, yields low limits of detection. The obtained volume refractive index detection limit of 5 × 10−6 refractive index units (RIU), and the surface mass density detection limit of 0.9 pg/mm2, shows that performance comparable to that of commercial non-integrated surface plasmon resonance sensors, made from bulk optical components, canbe achieved in a compact cartridge.
Qc20100715
SABIO

Стилі APA, Harvard, Vancouver, ISO та ін.

24

Nagarajan, Vivek Krishna. "Fluorescence Assisted Portable Cell Counting System." University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1376577419.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

25

Caroselli, Raffaele. "Development of high sensitivity photonic sensing structures based on porous silicon substrates." Doctoral thesis, Universitat Politècnica de València, 2018. http://hdl.handle.net/10251/107318.

Повний текст джерела

Анотація:

La salud y el bienestar siempre han sido el centro de atención de muchas instituciones de investigación y empresas de todo el mundo. Esto llevó a la tecnología a desarrollarse en los campos químico, biológico, médico y clínico con el objetivo de proporcionar una mejor protección al ser humano. Como consecuencia, ha surgido una competición entre el tiempo necesario para que la enfermedad progrese y el tiempo necesario para que el hombre trate dicha enfermedad. Para ganar esta competición, es necesario actuar con anticipación, cuando la enfermedad aún no está demasiado desarrollada. Esto es posible realizando una detección precoz de la enfermedad. El logro de este objetivo allana el camino para el desarrollo de dispositivos ópticos de biosensado capaces de detectar la presencia de ciertas moléculas en concentraciones extremadamente bajas. Entre ellos, las estructuras integradas fotónicas están teniendo un gran éxito debido a su considerablemente alta sensibilidad. Sin embargo, el mecanismo de detección de estas estructuras se basa en la interacción entre la onda evanescente, que se propaga a lo largo de la superficie de la estructura, y el analito a detectar. De esta forma, no todo el campo que se propaga en la estructura fotónica se usa con fines de detección, sino solo una pequeña cantidad de éste. Esto representa una limitación crucial de los sensores basados en fotónica integrada. El objetivo de esta tesis doctoral es superar esta limitación y desarrollar estructuras fotónicas de sensado más sensibles que sean capaces de detectar las concentraciones más bajas posibles. Con este objetivo, nos centramos en el estudio del silicio poroso como plataforma para el desarrollo de estructuras ópticas con sensibilidades extremadamente altas gracias a que la interacción de sensado se realiza directamente dentro de la propia estructura, lo que permite explotar todo el campo que se propaga.
Health and well-being have always been the center of attention of many research institutions and companies around the world. This led the technology to develop in the chemical, biological, medical and clinical fields with the aim to provide a better protection to the human being. As a consequence, a competition is born between the time necessary to the disease to progress and the time necessary to man to treat such disease. In order to win this competition, it is necessary to act with anticipation, when disease is not too developed yet. This is possible by performing an early-detection. The achievement of this goal paves the way for the development of optical biosensing devices able to detect the presence of certain molecules at extremely low concentrations. Among them, photonic integrated structures are finding a great success due to their considerably high sensitivity. However, the sensing mechanism of these structures is based on the interaction between the evanescent wave, propagating along the structure surface, and the target analyte to detect. In this way, not all the field propagating in the photonic structure is used for sensing purposes, but rather only a small amount of it. This represents a crucial limitation of the integrated photonics based sensors. The aim of this PhD Thesis is to overcome this limitation and to develop more sensitive photonic sensing structures able to detect the lowest concentration possible. To this aim, we focused on the study of porous silicon as platform for the development of optical structures with extremely high sensitivities thanks to the fact that the sensing interaction takes place directly inside the structure itself, allowing to exploit all the field propagating in the structure.
La salut i el benestar sempre han sigut el centre d'atenció de moltes institucions de recerca i empreses de tot el món. Açò va portar a la tecnologia a desenvolupar-se en els camps químic, biològic, mèdic i clínic amb l'objectiu de proporcionar una millor protecció a l'ésser humà. Com a conseqüència, ha sorgit una competició entre el temps necessari per que la malaltia progresse i el temps necessari per que l'home tracte aquesta malaltia. Per a guanyar aquesta competició, és necessari actuar amb anticipació, quan la malaltia encara no està massa desenvolupada. Açò és possible realitzant una detecció precoç de la malaltia. L'assoliment d'aquest objectiu facilita el camí per al desenvolupament de dispositius òptics de biosensat capaços de detectar la presència de certes molècules en concentracions extremadament baixes. Entre ells, les estructures fotòniques integrades estan tenint un gran èxit a causa de la seua considerablement alta sensibilitat. No obstant açò, el mecanisme de detecció d'aquestes estructures es basa en la interacció entre l'ona evanescent, que es propaga al llarg de la superfície de l'estructura, i l'analit a detectar. D'aquesta forma, no tot el camp que es propaga en l'estructura fotònica s'usa amb finalitats de detecció, sinó solament una xicoteta quantitat d'aquest. Açò representa una limitació crucial dels sensors basats en fotònica integrada. L'objectiu d'aquesta tesi doctoral és superar aquesta limitació i desenvolupar estructures fotòniques de sensat més sensibles que siguen capaces de detectar les concentracions més baixes possibles. Amb aquest objectiu, ens centrem en l'estudi del silici porós com a plataforma per al desenvolupament d'estructures òptiques amb sensibilitats extremadament altes gràcies a que la interacció de sensat es realitza directament dins de la pròpia estructura, el que permet explotar tot el camp que es propaga.
Caroselli, R. (2018). Development of high sensitivity photonic sensing structures based on porous silicon substrates [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/107318
TESIS

Стилі APA, Harvard, Vancouver, ISO та ін.

26

Beamer, Diane Krupp. "MINIMALLY INVASIVE OPTICAL SENSING OF GOLD AND SILVER NANOPARTICLE AGGREGATION:A PRELIMINARY INVESTIGATION." Miami University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=miami1376405013.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

27

Paturi, Naveen Kumar. "Analysis of photonic crystal defects for biosensing applications." Morgantown, W. Va. : [West Virginia University Libraries], 2006. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4861.

Повний текст джерела

Анотація:

Thesis (M.S.)--West Virginia University, 2006.
Title from document title page. Document formatted into pages; contains viii, 70 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 55-57).

Стилі APA, Harvard, Vancouver, ISO та ін.

28

Holmström, Nils Brage. "Optimal pacing with an implantable pO₂ sensor /." Stockholm : Tekniska högsk, 1999. http://www.lib.kth.se/abs99/holm0917.pdf.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

29

Loebel, Nicolas G. "Singlemode fiber interferometric biosensors /." Thesis, Connect to this title online; UW restricted, 1998. http://hdl.handle.net/1773/8026.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

30

Pal, Chandana. "Thin films of non-peripherally substituted liquid crystalline phthalocyanines A." Thesis, Brunel University, 2014. http://bura.brunel.ac.uk/handle/2438/8997.

Повний текст джерела

Анотація:

Three non-peripherally substituted liquid crystalline bisphthalocyanine (Pc) compounds have been studied to examine the role of central metal ions lutetium (Lu), and gadolinium (Gd) and substituent chain lengths, i.e. octyl (C8H17) and hexyl (C6H13), in determining the physical properties. For the octyl substituted Pc molecules, the head-to-tail or Jaggregates within the as-deposited spun films produced a redshift of the optical absorption Q bands in relation to their 0.01 mgml-1 solutions. Annealing at 80˚C produced a well-ordered discotic liquid crystalline (LC) mesophase causing additional redshifts irrespective of the metal ion in case of C8LuPc2 and C8GdPc2. Formation of face-to-face or H-aggregated monomers led to blueshifts of the Q bands with respect to solution spectra for C6GdPc2, both as-deposited and annealed films. Stretching and bending vibrations of pyrrole, isoindole, and metal-nitrogen bonds in Pc rings showed Raman bands at higher energy for smaller metal ion. However, no change was observed for the difference in chain lengths. As-deposited C8LuPc2 and C6GdPc2 produced comparable Ohmic conductivity, of the value 67.55 Scm-1 and 42.31 Scm-1, respectively. C8GdPc2 exhibited two orders of magnitude less conductivity than the other two due to the size effect of the central ion and side chain length. On annealing, an increase of Ohmic conductivity was noticed in the isostructural octyl substituted phthalocyanines on contrary to a reduced conductivity in hexyl substituted one. An optical band shift of the C8LuPc2 and C8GdPc2 thin films occurred on oxidation by bromine vapour. Oxidations of Pc-coated ITO were also achieved by applying potential at 0.88 V and 0.96 V electrochemically for the C8LuPc2 and C8GdPc2 compounds, respectively. To explore the applications of these compounds in biosensing, in situ interaction studies between bromine oxidised compounds and biological cofactors nicotinamide adenine dinucleotide (NADH) and L-ascorbic acid (vitamin C) were carried out using optical absorption spectroscopy. Thin films of a non-peripherally octyl substituted LC lead phthalocyanine was exposed to 99.9 % pure hydrogen sulfide gas to produce hybrid nanocomposites consisting of lead sulphide quantum dots embedded in the analogous metal free phthalocyanine matrix. Trapping of charge carriers caused hysteresis in the current-voltage characteristics of the film on interdigitated gold electrodes. The charge hopping distance was found to be 9.05 nm, more than the percolation limit and responsible for forming two well-defined conducting states with potential application as a memristor.

Стилі APA, Harvard, Vancouver, ISO та ін.

31

Karim, Farzia. "Active and Ultrasensitive Chemical and Biosensing through Optothermally Generated Microbubble." University of Dayton / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1591699029953022.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

32

Zhao, Xin. "Study of Multimode Extrinsic Fabry-Perot Interferometric Fiber Optic Sensor on Biosensing." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/34534.

Повний текст джерела

Анотація:

The electrostatic self-assembly (ESA) method presents an effective application in the field of biosensing due to the uniform nanoscale structure. In previous research, a single mode fiber (SMF) sensor system had been investigated for the thin-film measurement due to the high fringe visibility. However, compared with a SMF sensor system, a multimode fiber (MMF) sensor system is lower-cost and has larger sensing area (the fiber core), providing the potential for higher sensing efficiency.

In this thesis, a multimode fiber-optic sensor has been developed based on extrinsic Fabry-Perot interferometry (EFPI) for the measurement of optical thickness in self-assembled thin film layers as well as for the immunosensing test. The sensor was fabricated by connecting a multimode fiber (MMF) and a silica wafer. A Fabry-Perot cavity was formed by the reflections from the two interfaces of the wafer. The negatively charged silica wafer could be used as the substrate for the thin film immobilization scheme. The sensor is incorporated into the white-light interferometric system. By monitoring the optical cavity length increment, the self-assembled thin film thickness was measured; the immunoreaction between immunoglobulin G (IgG) and anti-IgG was investigated.
Master of Science

Стилі APA, Harvard, Vancouver, ISO та ін.

33

Joel, Smita. "ENGINEERING PROTEINS WITH UNIQUE CHARACTERISTICS FOR DIAGNOSTICS AND BIOSENSORS." UKnowledge, 2011. http://uknowledge.uky.edu/gradschool_diss/180.

Повний текст джерела

Анотація:

Proteins possess a broad range of structural and functional properties and, therefore, can be employed in a variety of biomedical applications. While a good number of protein-based biosensing systems and biosensors for target analytes have been developed, the search for versatile, highly sensitive and selective sensors with long term stability able to provide fast detection of target analytes continues to be a challenge. To that end, we now report the design and development of modified proteins with tailored characteristics and their further utilization in the development of biosensing systems. We take advantage of binding proteins that undergo a change in conformation upon binding to their respective target ligand analytes for the development of highly selective biosensing systems. The first class of binding proteins that was explored for this purpose was antibodies. A non-canonical site in the variable region of a monoclonal antibody was tagged with a fluorescent probe to sense the binding of analyte to its corresponding antigen-binding site. The strategy employed for designing antibodysensing molecules is universal as it can be employed for sensing any biomolecule of interest provided that there is an available antibody against the target ligand analyte. In a second strategy, we utilized designer glucose recognition proteins (GRPs) that were prepared by incorporation of unnatural amino acids in the glucose/galactose binding protein (GBP) of Escherichia coli and its truncated fragments. By taking advantage of the global incorporation method, we were able to fine-tune the binding affinity and thermal stability of the proteins, thus, allowing for the development of a reagentless fluorescence based fiber optic glucose biosensor capable of monitoring glucose in the hypoglycemic, normal, and hyperglycemic range, as well as in the hypothermic and hyperthermic temperature range.

Стилі APA, Harvard, Vancouver, ISO та ін.

34

De, Bonnault Sandie. "Conception, fabrication et caractérisation d'un biocapteur SPR à base de guides d'ondes photoniques sur substrat de verre." Thèse, Université de Sherbrooke, 2016. http://hdl.handle.net/11143/8957.

Повний текст джерела

Анотація:

Résumé : Malgré le nombre croissant de capteurs dans les domaines de la chimie et la biologie, il reste encore à étudier en profondeur la complexité des interactions entre les différentes molécules présentes lors d’une détection à l’interface solide-liquide. Dans ce cadre, il est de tout intérêt de croiser différentes méthodes de détection afin d’obtenir des informations complémentaires. Le principal objectif de cette étude est de dimensionner, fabriquer et caractériser un détecteur optique intégré sur verre basé sur la résonance plasmonique de surface, destiné à terme à être combiné avec d’autres techniques de détection, dont un microcalorimètre. La résonance plasmonique de surface est une technique reconnue pour sa sensibilité adaptée à la détection de surface, qui a l’avantage d’être sans marquage et permet de fournir un suivi en temps réel de la cinétique d’une réaction. L’avantage principal de ce capteur est qu’il a été dimensionné pour une large gamme d’indice de réfraction de l’analyte, allant de 1,33 à 1,48. Ces valeurs correspondent à la plupart des entités biologiques associées à leurs couches d’accroche dont les matrices de polymères, présentés dans ce travail. Étant donné que beaucoup d’études biologiques nécessitent la comparaison de la mesure à une référence ou à une autre mesure, le second objectif du projet est d’étudier le potentiel du système SPR intégré sur verre pour la détection multi-analyte. Les trois premiers chapitres se concentrent sur l’objectif principal du projet. Le dimensionnement du dispositif est ainsi présenté, basé sur deux modélisations différentes, associées à plusieurs outils de calcul analytique et numérique. La première modélisation, basée sur l’approximation des interactions faibles, permet d’obtenir la plupart des informations nécessaires au dimensionnement du dispositif. La seconde modélisation, sans approximation, permet de valider le premier modèle approché et de compléter et affiner le dimensionnement. Le procédé de fabrication de la puce optique sur verre est ensuite décrit, ainsi que les instruments et protocoles de caractérisation. Un dispositif est obtenu présentant des sensibilités volumiques entre 1000 nm/RIU et 6000 nm/RIU suivant l’indice de réfraction de l’analyte. L’intégration 3D du guide grâce à son enterrage sélectif dans le verre confère au dispositif une grande compacité, le rendant adapté à la cointégration avec un microcalorimètre en particulier. Le dernier chapitre de la thèse présente l’étude de plusieurs techniques de multiplexage spectral adaptées à un système SPR intégré, exploitant en particulier la technologie sur verre. L’objectif est de fournir au moins deux détections simultanées. Dans ce cadre, plusieurs solutions sont proposées et les dispositifs associés sont dimensionnés, fabriqués et testés.
Abstract : In spite of the growing number of available biosensors, many biochemical reactions and biological components have not yet been studied in detail. Among them, some require the combination of several detection techniques in order to retrieve enough information to characterize them fully. An unknown reaction based, for example, on DNA hybridization could be characterized with an electrochemical sensor, a mechanical sensor and an optical sensor, each giving a different type of information. The main objective of the work presented here is to design, fabricate and characterize a flexible integrated optical biosensor based on surface plasmon resonance, intended to be then combined with other detection techniques, and in particular, a microcalorimeter. Surface Plasmon Resonance (SPR) is well known to be a sensitive technique for surface-based biochemical detection. It has the advantage to be an unlabeled method and provides real time information on the kinetics of a reaction. The flexibility of the proposed SPR biosensor comes from the fact that it is designed for a large range of analyte refractive indices, from 1.33 to 1.48. These values are suitable for most biological entities and their ligand layers, and especially for hydrophilic polymer matrices used to trap DNA or protein entities and introduced in this work. As several biochemical studies require the simultaneous comparison of measurements to a reference or to another measurement, the second objective of this project is to study the potential of multi-analyte detection in an integrated SPR device on glass. The first three chapters of the thesis are focused on the main objective. The design based on two different models is presented, at the same time as the related simulation tools. The first model is based on the weak coupling approximation and permits to obtain most of the information for the device’s design. The second model, having no approximation, is used to validate the first model and complete and refine the design. The fabrication process of the glass chip is then introduced, as well as the characterization instruments and protocols. A device is obtained, with a volumetric sensitivity between 1000 nm/RIU and 6000 nm/RIU depending on the analyte refractive index. The 3D integration of the waveguide within the glass substrate makes the device extremely compact and adapted to the integration with the microcalorimeter in particular. The last chapter describes the study of several spectral multiplexing techniques adapted to an integrated SPR system using the glass technology. The goal is to provide at least two simultaneous measurements. Several detection techniques are examined and the related devices are designed, fabricated and characterized.

Стилі APA, Harvard, Vancouver, ISO та ін.

35

Bonnault, Sandie de. "Conception, fabrication et caractérisation d'un biocapteur SPR à base de guides d'ondes photoniques sur substrat de verre." Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAT040/document.

Повний текст джерела

Анотація:

Malgré le nombre croissant de capteurs dans les domaines de la chimie et la biologie, de nombreuses réactions n’ont pas encore été correctement identifiées et étudiées. C’est entre autres le cas des interactions intermoléculaires à l’interface liquide/solide trouvées dans les chimies de surface utilisées pour les méthodes de diagnostics médicaux et l’identification de divers processus biologiques. Afin de correctement comprendre les mécanismes en jeux, il est important de pouvoir croiser différentes méthodes de détection pour obtenir des informations complémentaires.MuLe principal objectif de cette étude est de dimensionner, fabriquer et caractériser un détecteur optique intégré sur verre basé sur la résonance plasmonique de surface, destiné à terme à être combiné avec d’autres techniques de détection. La résonance plasmonique de surface est une technique reconnue pour sa sensibilité adaptée à la détection de surface, qui a l’avantage d’être sans marquage et permet de fournir un suivi en temps réel de la cinétique d’une réaction. L’avantage principal de ce capteur est qu’il a été dimensionné pour une large gamme d’indice de réfraction de l’analyte, allant de 1,33 à 1,48. Ces valeurs correspondent à la plupart des entités biologiques associées à leurs couches d’accroche, particulièrement les matrices de polymères. Ces matrices sont de plus en plus utilisées non seulement pour leur capacité à augmenter la densité d’analytes présents à la surface du capteur, mais aussi pour leurs propriétés favorisant l’adsorption spécifique et leur utilisation comme élément actif de reconnaissance biologique.Étant donné que beaucoup d’études biologiques nécessitent la comparaison de la mesure à une référence ou à une autre mesure, le second objectif du projet est d’étudier le potentiel du système SPR intégré sur verre pour la détection multianalyte.MuLes trois premiers chapitres se concentrent sur l’objectif principal du projet. Le dimensionnement du dispositif suivant un cahier des charges préétabli est présenté, ainsi que les outils de simulation. Le procédé de fabrication de la puce optique sur verre est ensuite décrit, ainsi que les instruments et protocoles de caractérisation. Une comparaison est faite entre les simulations et les résultats expérimentaux, et les performances des outils numériques ainsi que celles du dispositif sont évaluées.Le dernier chapitre de la thèse présente l’étude de plusieurs techniques de multiplexage spectral adaptées à un système SPR intégré, exploitant en particulier la technologie sur verre. L’objectif est de fournir au moins deux détections simultanées. Dans ce cadre, plusieurs solutions sont proposées et les dispositifs associés sont dimensionnés, fabriqués et testés
In spite of the growing number of available biosensors, many biochemical reactions and biological components have not yet been studied in detail. Among them, some require the combination of several detection techniques in order to retrieve enough information to characterize them fully. An unknown reaction based, for example, on DNA hybridization could be characterized with an electrochemical sensor, a mechanical sensor and an optical sensor, each giving a different type of information.MuThe main objective of the work presented here is to design, fabricate and characterize a flexible integrated optical biosensor based on surface plasmon resonance, intended to be then combined with other detection techniques. Surface Plasmon Resonance (SPR) is well known to be a sensitive technique for surface-based biochemical detection. It has the advantage to be an unlabeled method and provides real time information on the kinetics of a reaction. The use of an integrated technology enables us to integrate several sensors on the same chip for the same sample, making them compact and low-cost. The flexibility of the proposed SPR biosensor comes from the fact that it is designed for a large range of analyte refractive indices, from 1.33 to 1.48 in the 600 nm-1000 nm wavelength range. These values are suitable for most biological entities and their ligand layers, and especially for hydrophilic polymer matrices used to trap DNA or protein entities. These biochemical matrices are used more and more for their ability to trap high densities of analyte, provide a strong binding and serve as an active detection medium with good anti-fouling properties.MuAs several biochemical studies require the simultaneous comparison of measurements to a reference or to another measurement, the second objective of this project is to study the potential of multianalyte detection in an integrated SPR device on glass.The first three chapters of the thesis are focused on the main objective. The design according to predefined specifications is presented, at the same time as the simulation tools. The fabrication process of the glass chip is introduced, as well as the characterization instruments and protocols. Simulation and experimental results are then compared, and the device performance is assessed.The last chapter describes the study of several spectral multiplexing techniques adapted to an integrated SPR system using the glass technology. The goal is to provide at least two simultaneous measurements. Several detection techniques are examined and the related devices are designed, fabricated and characterized

Стилі APA, Harvard, Vancouver, ISO та ін.

36

Sendowski, Jacob Benjamin. "On-Chip Integrated Label-Free Optical Biosensing." Thesis, 2013. https://thesis.library.caltech.edu/7812/1/JS_Thesis.pdf.

Повний текст джерела

Анотація:

This thesis investigates the design and implementation of a label-free optical biosensing system utilizing a robust on-chip integrated platform. The goal has been to transition optical micro-resonator based label-free biosensing from a laborious and delicate laboratory demonstration to a tool for the analytical life scientist. This has been pursued along four avenues: (1) the design and fabrication of high-$Q$ integrated planar microdisk optical resonators in silicon nitride on silica, (2) the demonstration of a high speed optoelectronic swept frequency laser source, (3) the development and integration of a microfluidic analyte delivery system, and (4) the introduction of a novel differential measurement technique for the reduction of environmental noise.

The optical part of this system combines the results of two major recent developments in the field of optical and laser physics: the high-$Q$ optical resonator and the phase-locked electronically controlled swept-frequency semiconductor laser. The laser operates at a wavelength relevant for aqueous sensing, and replaces expensive and fragile mechanically-tuned laser sources whose frequency sweeps have limited speed, accuracy and reliability. The high-$Q$ optical resonator is part of a monolithic unit with an integrated optical waveguide, and is fabricated using standard semiconductor lithography methods. Monolithic integration makes the system significantly more robust and flexible compared to current, fragile embodiments that rely on the precarious coupling of fragile optical fibers to resonators. The silicon nitride on silica material system allows for future manifestations at shorter wavelengths. The sensor also includes an integrated microfluidic flow cell for precise and low volume delivery of analytes to the resonator surface. We demonstrate the refractive index sensing action of the system as well as the specific and nonspecific adsorption of proteins onto the resonator surface with high sensitivity. Measurement challenges due to environmental noise that hamper system performance are discussed and a differential sensing measurement is proposed, implemented, and demonstrated resulting in the restoration of a high performance sensing measurement.

The instrument developed in this work represents an adaptable and cost-effective platform capable of various sensitive, label-free measurements relevant to the study of biophysics, biomolecular interactions, cell signaling, and a wide range of other life science fields. Further development is necessary for it to be capable of binding assays, or thermodynamic and kinetics measurements; however, this work has laid the foundation for the demonstration of these applications.

Стилі APA, Harvard, Vancouver, ISO та ін.

37

Chen, Wei. "Synthesis of Optical Nanodevices with Application in Biosensing." Thesis, 2010. http://spectrum.library.concordia.ca/7455/1/Chen_MASc_s2011.pdf.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

38

Ahl, Stefanie Elisabeth [Verfasser]. "New platforms for optical biosensing / Stefanie Elisabeth Ahl." 2007. http://d-nb.info/985594470/34.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

39

Liu, G. W., and 劉廣惟. "Development and Application of nano optical probe on biosensing." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/82229727331304389132.

Повний текст джерела

Анотація:

碩士
國立臺灣海洋大學
光電科學研究所
94
Recently, the biosensing has attracted much attention in twenty-one century. SPR has drawn extensive attention for application in biosensing, but traditional SPR setup is typically bulky, expensive and requires a large amount of sample solution. In this thesis, we have performed the new SPR sensing devices which have many advantages such as easily fabrication and high capability. We used nano optical probe to induce surface plasmon resonance and measure the specimen by SPR. The numerical simulations are performed by using FDTD method. The result of FDTD simulations indicate the SPW generated near the probe tip. Finally, we used BSA binding on nano optical probe, and it was concluded that the biomedical application have verified by measuring the antigen-antibody interactions.

Стилі APA, Harvard, Vancouver, ISO та ін.

40

Fan, Ching-Yu, and 范瀞予. "Measurement Analysis and Biosensing Applications of Optical Microcantilever Sensor." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/60927516130935267205.

Повний текст джерела

Анотація:

碩士
國立臺灣大學
土木工程學研究所
104
With the development of micro- and nanofabrication technique, a variety of chemical or physical responses of molecular adsorption can be translated into measurable deformation and detected by tiny devices, including doubly clamped beams, membrane, and cantilever, who has one of dimensions in micro- or nanoscale. These devices are referred to as nanomechanical biosensors. With the advantages of ease of measurement and high sensitivity, nanomechanical biosensors are expected to play a promising role in the field of biosensing. In this thesis, we focus on development of the optical microcantilever sensor, including the calibration method, measurement analysis, and the application in the study of chain length effect of self-assembled monolayer (SAM) and drug detection. Firstly, based on the geometrical method, a calibration between signals of the position sensitive detector (PSD) and deflections of the microcantilever is obtained. By utilizing the concept of error propagation, the standard error of deflections calibrated from the PSD signals are defined. Secondly, experiments on the chain length effect of SAM under temperature change are conducted with the proposed calibrated method. Finally, the drug detection of valproic acid is performed with the optical microcantilever sensing platform proposed herein. In this study, we successfully developed a calibration method of measurements, with the definition of accuracy, for the optical microcantilever sensor. The factors resulting in measurement error were found through the measurement analysis. In the experiments of the chain length effect of SAM, we found that the relationship between chain length of SAM and thermal-induced differential surface stress had a turning point when chain length was equal to six. A similar trend was identified when we conducted simulations using Molecular Dynamics simulation (MD). Further calculations of entropy and enthalpy were performed and we found that the change of thermal-induced differential surface stress with the change of chain length was governed by the competition of entropy and enthalpy. In the final part of this thesis, the detection of valproic acid by using the optical microcantilever sensor was performed. The response of molecular adsorption cannot be distinguished from the noise. However, the methods and the standard steps of conducting drug detection experiments were established.

Стилі APA, Harvard, Vancouver, ISO та ін.

41

Kaur, Kanwarjeet. "Optical Biosensing Using Localized Surface Plasmon Resonance of Gold Nanoparticles." Thesis, 2011. http://hdl.handle.net/10012/5983.

Повний текст джерела

Анотація:

This thesis describes some experiments developed to probe the fundamental aspects of the interfacial behaviour of proteins. The contents of this thesis can be broadly divided into two parts. In the first part, we studied how the size of the nanoparticles and other variables such as pH and bulk protein concentration affect the structure of the adsorbed protein layers. We also probed how these factors can influence the binding activity of adsorbed proteins. Study on the adsorption of IgG, Protein A and streptavidin on gold nanoparticles reveals that not all proteins are similarly affected by the size of the adsorbing surface. We found that though the optical properties of all the proteins vary with the size of the nanoparticle, their functionalities are not similarly affected by nanoparticle curvature. Protein A and streptavidin retain their binding capacity to IgG and biotin, respectively, irrespective of the size of the gold nanoparticle that they are attached to. On the other hand, a reduction/ loss in binding of adsorbed IgG to Protein A molecules is observed. The reduction in biological activity further depends on the radius of curvature of the adsorbing surface. The second part of the thesis describes how nanoparticles can used as a probe to study the complex interfacial behaviour of proteins. We have utilized the extreme sensitivity of localized surface plasmon resonance (LSPR) of gold nanoparticles to local refractive index to determine the optical properties of BSA adsorbed on various polymer surfaces. The dielectric properties of the adsorbed protein depend on the nature of the substrate. Further, we have developed a model to determine the refractive index profile of adsorbed protein as a function of the distance from the substrate.

Стилі APA, Harvard, Vancouver, ISO та ін.

42

SANG, JIA-YU, and 宋家裕. "Development of Reflection-Based Optical Waveguide Particle Plasmon Resonance Biosensing Platforms." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/68801620211485505316.

Повний текст джерела

Анотація:

碩士
國立中正大學
化學暨生物化學研究所
104
The objectives of this work are to develop two novel multiplex chemical and biochemical sensing platforms, namly a reflection-based tubular waveguide particle plasmon resonance (RTW-PPR) biosensing platform, and a reflection-based fiber optic particle plasmon resonance (RFO-PPR) biosensing platform. The principle of inventions are based on measuring the light intensity after consecutive total internal reflections (TIRs) along a noble metal nanoparticles-modified waveguide (tube or optical fiber), wherein the evanescent wave excites the particle plasmon resonance of the nanoparticles at the reflection interface. When a noble metal nanoparticle is influenced by the change of the refractive index on its surrounding environment, its particle plasmon resonance condition will change. This phenomenon can be used as the basis of chemical and biological sensing. In the first part ：we used Poly(methyl methacrylate) PMMA as waveguide material to form a tubular waveguide and utilized 3-mercaptopropylsilatrane (MPS) to reduce the modification time. A variety of experiments were carried out to validate the sensitivity and refractive index resolution of the sensing platform. Using different weight percent of sucrose in pure water as samples, a refractive index resolution of 4.34×10-5 RIU and a sensor sensitivity of 5.39 RIU-1 have been achieved by the platform. In the biochemical detection experiments, OVA was used to functionalize the gold nanoparticle in order to detect anti-OVA. Results show that the calibration curve is linear (R2>0.99) and the limit of detection (LOD) is about 4.64×10-6 g/mL (3.09×10-8 M). In the second part：the RFO-PPR platform has achieved the absorbance sensitivity of 4.83 AU/RIU-1 and the sensor resolution of 4.6×10-5 RIU by using gold nanospheres as the sensing element. By the similar configuration, but using gold nanorods as the sensing element, the absorbance sensitivity of 3.81 AU/RIU-1 and the sensor resolution of 3.7×10-5 RIU have been achieved. In the biochemical detection experiments, DNP was used to functionalize the gold nanorods in order to detect anti-DNP antibody. Results show that the calibration curve is linear (correlation coefficient >0.99) and the detection limit is less than 3.88×10-10 M.

Стилі APA, Harvard, Vancouver, ISO та ін.

43

Lin, Yi-Chang, and 林奕昌. "Detection of Optical Biosensing Arrays Using White Light Fourier Transform Method." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/52049592017020892257.

Повний текст джерела

Анотація:

碩士
國立暨南國際大學
應用材料及光電工程學系
102
In recent years, surface plasmon resonance technique has been widely used in optical sensing. Optical biosensors detect the binding energy between bio-molecules using the resonance or propagation behavior of light under different environments. Conventionally, the optical biosensor based on surface plasmon resonance needs an extra prism to couple light to the sensor. Complicated and accurate adjustment is required for phase matching between the surface plasmon wave and the incident light. In recent years, some research works have shown that surface plasmon wave can be excited when light passing through the periodic metallic nanostructures directly, without coupling via a prism. In this study, the optical sensor is designed as a chip-based gold nanoslit array structure. A TM-polarized light is normally incident on the gold nanoslit array with the analyte on top of it. The surface plasmon wave is then excited on the gold surface. The transmission spectrum is measured to detect the interaction between sensing analytes through analyzing the resonance wavelength shifts or intensity changes of the spectrum. The gold nanoslit array is designed as a two-by-two matrix, with slit period 500nm, structure area 5 mm×5 mm, slit depth 150 nm, and the slit width 60 nm. The sample was encapsulated with acrylic as a microfluidic chip, which stabilizes the environment during liquid injection. The experimental set up combines a bright field microscopy with a white-light Fourier spectrometer based on a Michelson interferometer system. In the Michelson interferometer system, the optical path difference is controlled between 0 to 35 μm. The interference pattern is recorded by a charge-coupled-device (CCD) camera as an interferogram. The interferogram is later transformed into spectrum by Fourier analysis using MatlabR software. In this work, the gold nanoslit array was covered by glycerin solution with different concentration. The refractive index of glycerin solution varies from 1.33 to 1.38. Transmission spectra under different environmental index are detected. The wavelength sensitivity, defined as resonance wavelength changes with refractive index, is measured as 213 nm/RIU (refractive index unit). Since the linearity of wavelength sensitivity is not good enough, we further use a center mass method to improve the linearity. The measured wavelength sensitivity under center mass method is 130 nm/RIU. Although the sensitivity is lower, a better linearity is obtained. Moreover, the intensity sensitivity, defined as intensity changes with refractive index, is measured as 99 %/RIU. To increase intensity sensitivity, a multispectral integration method is used. An increased sensitivity of 2078 %/RIU is obtained. Furthermore, the detection of the binding between bovine serum albumin (BSA) and bovine protein antibodies (anti-BSA) are measured, with BSA concentration 6.06 μM and anti-BSA 60 nM. The multispectral integration method is used to analyze the experimental results for better intensity sensitivity. Experimental results show that the binding between BSA and anti-BSA can be easily detected by the spectra change. Key words：Surface plasmon resonance, White-light Fourier spectrometer

Стилі APA, Harvard, Vancouver, ISO та ін.

44

Fan, Shu-Yu, and 范書毓. "Fiber-optical biosensing platform for quantifying cell population or tissue level activities." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/87907459896605344892.

Повний текст джерела

Анотація:

碩士
國立中興大學
生醫工程研究所
101
A fiber-optical biosensing platform in coordination with localized fluidic delivery to perform topical cell-scale assay inside living tissue or organs in vivo. The deviation from the cell density and spatial configuration in the vicinity of sensor probe can cause error in threshold value determination, which is difficult for the conventional extrinsic catheter fiber-optic designs to predict or calibrate for in vivo applications. The strategy for correcting / calibrating the difference from the spatial issue is to stain the cells with two fluorescent agents. The 1st fluorophore (indicator) will has a known effect on all cells which is not affected by the conditions (“normal / control” or “treated” with desired physiological changes) of the cells; the signal from the indicator will be considered as “baseline” reflecting each independent measurement with specific density and configuration of the cells in the vicinity of sensor tip. The 2nd fluorophore (reporter) will exhibit level of physiological change on “treated” cells. The significance of the physiological changes on individual cell will be evaluated by the ratio of the two fluorescent signals (reporter / indictor) to report the normalized deviation between “control” and “treated” cell population. In this research, we applied the fiber-optic sensor platform in monitoring chemotherapeutic, cyclophosphamide (CPA), induced 3D-distributed MCF-7 cell (human breast carcinoma cell line) apoptosis for verifying the feasibility and capability of the system in monitoring cell population or tissue level activities in vivo. In the 1st stage of the development, 25mM CPA was found to enhance apoptosis of cancer cells in cell viability (MTT) assay under 2D cell culture, increase the adsorption amount of fluorophore FM 1-43 on apoptotic cells, but had no effect on the adsorption amount of indocyanine derivatives on apoptotic cells. In the 2nd stage of study, the fiber-optic sensing platform monitored the kinetics of fluorescence changes around the micro-environment of sensor tip with a 200μm i.d. optical fiber, conveying the excitation and returning emission, and a 325μm i.d. microcapillary initially delivering fluorophore, 750nl 300 μm naphthalene asymmetric indocyanine derivative (Cpd.B), in indicating the spatial distribution (density) of cells in the tissue-mimic system, following by delivering fluorophore, 750nl 160μM FM1-43, in demonstrating the apoptotic activity induced by CPA after calibrated with the previous Cpd.B reported cell distribution indicating signal. When cell density exceeded 107cells/ml, the increase percentage of peak values in dynamic fluorescent change pattern of Cpd.B were in proportion to cell densities, but not correlated statistically with CPA-induced apoptotic activities. However, the increase percentages of peak values in dynamic fluorescent change pattern of FM 1-43 were in proportion to both cell densities and CPA-induced apoptotic activities. In the cell density between 107-108cells/ml, the increase percentage of peak values in dynamic fluorescent change pattern from FM 1-43 interacted with CPA-induced apoptotic cells were 2.1-3.3 folds of peak values from FM 1-43 interacted with control cell. When sequentially interacted with Cpd.B and FM 1-43, the ratios from increase percentage of peak values of FM 1-43 divided by increase percentage of peak values of Cpd.B were around 0.71-1.58 in the control cells with different densities, while the ratios from CPA-induced apoptotic cells were around 3.62-10.68. The value of ratio could be applied as indication of apoptotic activity without interference of spatial distribution of cells. The preliminary result verified the feasibility and capability of the system in monitoring cell population or tissue level activities in vivo.

Стилі APA, Harvard, Vancouver, ISO та ін.

45

Waly, Noha [Verfasser]. "Optimization of core-shell nanoparticle layers for optical biosensing / presented by Noha Waly." 2011. http://d-nb.info/1010842811/34.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

46

Lin, Chi-Hao, and 林琪皓. "Electro-Optical and Capacitive Measurements for Quantitative Analysis of Liquid-Crystal-Based Biosensing." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/u7jtxk.

Повний текст джерела

Анотація:

碩士
國立交通大學
影像與生醫光電研究所
104
The texture observation has long been the core technique in liquid crystal (LC)-based biosensing. However, quantitative analysis of this method for determining the biomolecular concentration can hardly be realized since the existence of biomolecules immobilized on the substrate is examined in accordance with the brightness of optical textures. In considering with the electrical response of birefringence and dielectric anisotropy of LC materials, in this study, two approaches―electro-optical and capacitive measurements, are proposed specifically for quantitative analysis of LC-based biosensing. Here, the biomolecule used is bovine serum albumin (BSA), a protein standard commonly used in the assay of protein concentration, and the LC material used as the sensing platform is highly birefringent HDN with positive dielectric anisotropy. Experimental results indicate that the detection limit of the BSA concentration is 106 g/ml for the electro-optical measurement and is 109 g/ml for the electric capacittance measurement. The difference between the detection limit of the two measurements stems from the method used for the immobilization of BSA on the DMOAP-coated substrates. For the electro-optical measurement, the BSA biomolecules were spin-coated on the substrate to reduce percentage error on the calculation of phase retardation, attributable to the light scattering. By measuring voltage-dependent transmission (VT) curves and calculating phase retardations of experimental samples, we propose an N value, defined as the ratio of the effective refractive index of the sample to the birefringence of the LC material, to quantitatively estimate the influence of the BSA concentration on the orientation of LC molecules. On the other hand, samples used for the capacitive measurement were prepared using droplets to attach protein on the substrates. Experimental results based on the voltage-dependent capacitive (VC) curves render information on the maximum capacitance Cmax and the capacitance difference ΔC. Furthermore, a quantitative value defined as the ratio of Cmax to ΔC of a sample driven by external AC voltages is calculated to analyze the relationship between the LC tilted angle and the BSA concentration.

Стилі APA, Harvard, Vancouver, ISO та ін.

47

"Dependence of surface plasmon polaritons on the geometry of periodic metallic nanostructures and Its application on biosensing." 2012. http://library.cuhk.edu.hk/record=b5549441.

Повний текст джерела

Анотація:

由於表面等離子體激元可以將電磁場限制在金屬表面，從而產生強烈的場強增強效果，因此在納米光子學和生物光子學方面具有廣泛的應用價值，其中包括高性能發光二級管、光伏電池、超高分辨率光學成像和超靈敏分子檢測等。尤其在單分子和醫學診斷方面，基於表面等離子體共振的生物傳感器獲得了越來越多的青睞。本論文包括兩部份。第一部份著重討論二維週期性洞陣列的表面等離子體特性，而第二部份則是研究這種洞陣列結構在表面等離子體共振傳感方面的應用。
在第一部份中，表面等離子體模式被分為非簡並模式(m，O) 和簡並模式(m，±n)兩種情況分別加以討論。首先，結合實驗結果和理論模型，我們對非簡並模式的衰減壽命和激發效率進行了研究。通過光干涉光刻法和薄膜沉積技術，一系列不同幾何結構的洞陣列樣品被製備出來，且這些樣品具有很高的重複性。利用角分辨色散關係進行模式識別以及確定這些模式的衰減壽命和激發效率。通過調整起偏器和檢偏器的相對方向，表面等離子體模式的非輻射和輻射衰竭均可加以研究。結果發現，衰減壽命強烈依賴於單洞的幾何結構，而且這種行為可以用簡單的靜電模型并考慮高階修正加以解釋。從非輻射衰減和輻射衰減平衡的角度出發，激發效率對幾何結構和共振波長的依賴性也可以理解。對於簡并模式，由於存在稱合，對稱模式和反對稱模式分別被p 偏振激發和S偏振激發。它們的對稱性和對於衰減壽命和共振波長的修正可以用干涉法和模式耦合理論來理解。最後，利用多模耦合方程，我們對色散關係圖譜隨著洞深度增加而演化的情況也進行了探討。
第二部份對基於表面等離子體共振的生物傳感器與陣列幾何結構的關係進行了研究。結果發現，激發效率和衰減壽命對表面等離子體共振傳感器的分辨率都起到了關鍵性作用。在共振中，峰值高度和帶寬主要由表面等離子體的衰減速率控制。較低的衰減速率導致較清晰的峰值線型，從而產生較高的傳感器分辨率。因此，通過調整陣列的幾何結構以產生非常低得輻射衰減速率，表面等離于體共振傳感器的品質因數可高達104.8/RIU ，這已經超過了基於梭鏡和納米粒子對應器件的性能表現。
Surface plasmon polaritons (SPPs) generate a strong localized electromagnetic field on metal surface and thus are promising for nano- and bio-photonics including high performing light-emitting diodes and photovoltaic cells, super-high resolution optical imaging, ultra-high sensitive bimolecular detection, etc. In particular, the application of SPPs on surface plasmon resonance (SPR) biosensor has drawn much more attention recently because of the attempt to realize single molecule detection in medical diagnosis.
This thesis contains two parts. The first part focuses on studying the basic plasmonic properties of two-dimensional periodic hole arrays while the second part concentrates on the application of hole arrays on SPR sensing.
In the first part, SPPs modes on hole arrays are classified into nondegenerate mode (m, 0) and degenerate mode (m, ±n). For nondegenerate mode, its decay lifetime and generation efficiency are studied both experimentally and theoretically. By combining interference lithography and thin film deposition, a set of arrays with a wide range of geometry has been fabricated with high reproducibility. The dispersion relations of arrays are studied by angle-dependent reflectivity for mode identification and detenninations of SPP decay lifetime and generation efficiency. In particular, through orienting the polarization of the specular reflection either parallel or orthogonal to that of the incidence, we can access both the nonradiative and radiative decays of SPPs at different resonance wavelengths. As a result, it is found that decay lifetime is strongly dependent on the geometry of single hole and its behaviors can be understood by using a simple quasi-static model taking into account of the higher order correction as well as numerical simulation deduced by finite-difference timedomain. The dependence of generation efficiency on hole geometry or resonance wavelength can be understood in tenns of trade-off between nonradiative and radiative decay rates. Once these two decay rates equals to each other, the optimum generation efficiency is realized and the field enhancement gets the maximum. And the optimum parameters can be achieved by adjusting the hole geometry or the resonance wavelength. For degenerate mode, due to the coupling between (m, +n) and (m, -n) modes, a symmetric and an anti-symmetric modes are excited under pand s-polarized excitation, respectively. Their symmetries and modifications to the decay lifetime and resonance wavelength can be understood by using the interference method and coupled mode theory. Finally, generalized coupled mode equations are employed to know about the evolution of dispersion relation as hole depth increases.
The dependence of SPR biosensor on the generation and decay of SPPs are studied in the second part. Both the generation efficiency and decay lifetime of SPPs are found to be critical in governing the resolution of SPR biosensor. In SPR, the peak height and linewidth are primarily controlled by the decay rate of SPPs. Lower decay rate leads to sharper peak profile, which results in higher SPR resolution. Therefore, by tailoring the geometry of hole arrays to achieve a very low radiative decay rate, a SPR biosensor with figure of merit (FOM) reaching l04.8/RIU can be realized, which surpasses those of prism and nanoparticle counterparts.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Zhang, Lei = 表面等離子體激元對於週期性金屬納米結構幾何形狀的依賴性及其在生物傳感中的應用 / 張磊.
"November 2011."
Thesis (Ph.D.)--Chinese University of Hong Kong, 2012.
Includes bibliographical references (leaves 116-125).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstract also in Chinese.
Zhang, Lei = Biao mian deng li zi ti ji yuan dui yu zhou qi xing jin shu na mi jie gou ji he xing zhuang de yi lai xing ji qi zai sheng wu chuan gan zhong de ying yong / Zhang Lei.
Chapter Chapter1 --- Introduction --- p.1
Chapter Chapter2 --- Theoretical Background --- p.7
Chapter 2.1 --- Maxwell's equations --- p.7
Chapter 2.2 --- Classic electromagnetic theory for dielectric properties of matter --- p.9
Chapter 2.3 --- Surface plasmon polaritons at the dielectric/metal interface --- p.11
Chapter 2.4 --- Excitation of surface plasmon polaritons --- p.16
Chapter 2.4.1 --- Prism coupling --- p.17
Chapter 2.4.2 --- Grating coupling --- p.17
Chapter 2.5 --- lones calculus --- p.19
Chapter 2.6 --- Finite-difference time-domain method --- p.22
Chapter Chapter 3 --- Sample Preparation --- p.25
Chapter 3.1 --- Interference lithography --- p.25
Chapter 3.1.1 --- Substrate preparation --- p.26
Chapter 3.1.2 --- Exposure --- p.27
Chapter 3.1.3 --- Pattern development --- p.30
Chapter 3.2 --- Thin film deposition --- p.30
Chapter Chapter 4 --- Experimental Setups and Calibration --- p.33
Chapter 4.1 --- Experimental setup for measuring dispersion relation --- p.33
Chapter 4.2 --- Experimental setup calibration --- p.35
Chapter 4.2.1 --- Calibration of spectrometer --- p.36
Chapter 4.2.2 --- Calibration of movement stages --- p.38
Chapter 4.3 --- Data presentation for dispersion relation --- p.40
Chapter 4.4 --- Summary --- p.41
Chapter Chapter 5 --- Understanding of Fundamental Properties of SPPs --- p.43
Chapter 5.1 --- Excitation of SPPs on 2D hole arrays --- p.44
Chapter 5.2 --- Properties of non degenerate modes and theoretical explanation --- p.53
Chapter 5.2.1 --- Dependence of lifetime on hole geometry and theoretical explanation --- p.55
Chapter 5.2.2 --- Dependence of generation efficiency on hole geometry and theoretical explanation --- p.63
Chapter 5.3 --- Properties of degenerate modes and theoretical explanation --- p.70
Chapter 5.3.1 --- Dependence of properties of degeneration modes on hole geometry by FDTD --- p.72
Chapter 5.3.1.1 --- (0, ±l)[subscript s,a] modes --- p.72
Chapter 5.3.l.2 --- (-1, ±l)[subscript s,a] modes --- p.76
Chapter 5.3.2 --- Understanding of excitation of degenerate modes by using interference method --- p.79
Chapter 5.3.3 --- Understanding of coupling between degenerate modes by using coupled mode theory --- p.85
Chapter 5.4 --- Evolution of dispersion relation as hole depth increases --- p.90
Chapter 5.5 --- Summary --- p.95
Chapter Chapter 6 --- Surface Plasmon Resonance Based Label Free Biosensor --- p.98
Chapter 6.1 --- Basics of surface plasmon resonance (SPR) based biosensor --- p.98
Chapter 6.2 --- State-of-the-art SPR biosensor --- p.101
Chapter 6.3 --- SPR biosensor by using 2D metallic hole arrays --- p.102
Chapter 6.4 --- Summary --- p.111
Chapter Chapter 7 --- Conclusions --- p.112
References --- p.116
Publications --- p.126

Стилі APA, Harvard, Vancouver, ISO та ін.

48

Lee, Kuang-Li, and 李光立. "The Properties of Optical Wave in Periodic Metallic Nanostructures and Its Application in Biosensing." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/68727467947839775407.

Повний текст джерела

Анотація:

博士
國立臺灣大學
光電工程學研究所
96
In this dissertation, a detailed study of the optical properties of single metallic nanoslit and multiple metallic nanoslits is presented. In experiment, high sensitive, label-free, high-throughput, reusable, and chip-based biosensor arrays based on surface and gap plasmon resonance were fabricated and tested. In the study of optical properties of metallic nanostructures, metallic nanoslits with periods varying from 400 to 900 nm and widths ranging from 20 to 200 nm were fabricated on a thin gold film using e-beam lithography and reactive ion etching. The thickness of the gold film is varying from 100 to 200 nm and the area of the metallic nanoslit array is chosen as 100 µm×100 µm. Experimental results show that gap plasmon resonance in the slit generates a peak with a broader full-width half-maximum in the transmission spectrum and the peak wavelength is affected by slit width and film thickness. That’s due to surface plasmon resonances outside the slit play a negative role in optical transmission and present a dip in the transmission spectrum. Besides, a peak accompanying an SPR dip can be predicted by Rayleight anomaly. The peaks or dip is sensitive to the refractive index change of the environment and can be applied in biological or chemical sensing. In the application of biological detection, SPR biosensor achieved a detection sensitivity of up to 740 nm per refractive index unit and an antigen–antibody interaction experiment in an aqueous environment verified the sensitivity in a surface binding event. The surface sensitivities of surface and gap plasmons were compared by coating a thin SiO2 film and different biomolecules on the nanoslit arrays. Experimental results show gap plasmons are more sensitive than conventional surface plasmons. The gap plasmons can detect a 0.05 nm-thick SiO2 film and ~4 Da-sized biomolecules attached to the surface when the resolution of a spectrometer is 0.1 nm. Besides, its detection sensitivity is increased with the decrease of the slit width. The gap plasmon is one order of magnitude more sensitive than the surface plasmon for slit widths smaller than 30 nm. In the 13-nm-diameter gold nanoparticle detection, gap plasmon is 3 times more sensitive than surface plasmon. A detection sensitivity of 1 particle/µm2 was achieved with a 0.1 nm wavelength shift or a 0.2% peak intensity change. This sensitivity is comparable with that of the fluorescent dyes ~0.5 fluors/µm2 used in DNA microarrays. Such a high sensitivity is attributed to the large overlap between biomolecules or nanoparticles and nanometer-sized gap plasmons.

Стилі APA, Harvard, Vancouver, ISO та ін.

49

Ho, Po-Ching, and 何柏慶. "Localized Surface-Plasmon-Resonance Biosensing System by Electro-Optical Modulation in the ATR Configuration." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/m78v64.

Повний текст джерела

Анотація:

碩士
國立臺北科技大學
光電工程系研究所
97
In this dissertation, we present an electro-optically modulated localized surface plasmon resonance biosensing system in the attenuated-total-reflection configuration, which can be used to measure the concentration of biochemical material. The sensing chip consists of a sensing region and one pair of electrodes on the ridge structure. When the voltage is applied on the electrodes, the electric field produced in lithium niobate electro-optically modulates the refraction index and changes the wave vector of the incidence lightwave. In this study, we use two kinds of measurement configurations, including optical intensity and phase shift configuration. Excited layer of surface plasmon formed by gold nanoparticle on gold film is adopted in the sensor. Human serum albumin (HSA) produced by the self-assembling method is used as the sensing layer to real-time sense the concentration of beta-blocker, which is a kind of medicine for heart disease. During the sensing measurement, the concentration of beta-blocker can be determined by the relation between the reflection intensity (or the phase shift) and the voltage. In comparison with the conventional SPR sensing, the proposed SPR sensing system has many advantages, such as: high accuracy, high sensitivity, and easy operation. In the future application, the presented biosensing system can be utilized to measure the interaction between HSA and medicines molecule for understanding the interaction mechanism of medicine in the human body.

Стилі APA, Harvard, Vancouver, ISO та ін.

50

Enders, Dominik [Verfasser]. "Surface enhanced infrared absorption on Au nanoparticle films for optical biosensing / presented by Dominik Enders." 2006. http://d-nb.info/97824673X/34.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Дисертації з теми "Optical Biosensing"

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями