Surface plasmon resonance, internal

Eland-Eleld Immunochromatographic Assay (Tetracore) Fiber-Optic Waveguide (NRL, Research International) Surface Plasmon Resonance (University of Washington, Battelle)... 

Homola J., Dostalek J., Chen S., Rasooly A., Jiang S., Yee S.S., Spectral surface plasmon resonance biosensor for detection of staphylococcal enterotoxin B (SEB) in milk, Intern. J. Food Microbiology 2002 75 61-69. 

Figure 2. Regular reflectance Replication of Snellius law for reflected and refracted radiation at interface in dependence on the refractive indices of the media adjacent to this interface, demonstrating total internal reflectance and evanescent field, exciting fluorophores close to the waveguide or even surface plasmon resonance.

J. Homola, J. Dostalek, S. F. Chen, A. Rasooly, S. Jiang, and S. S. Yee, "Spectral Surface Plasmon Resonance Biosensor for Detection of Staphylococcal Enterotoxin B(SEB) in Milk," International Journal of Food Microbiology 75, 61-69 (2002). 

Optical devices have also been used as transducers. Laser fiber-optics allows high intensity light to travel a long distance using fibrous size carrier. The stable and intense light beam not only provides calibration stability but also makes all the detecting techniques faster and more sensitive. In addition to the UV-VIS absorbance and fluorescence intensity, measurements of multiple reflections, surface plasmon resonance, and total internal reflection fluorescence had recently been used (12, 13, 14). 

Apart from optical microscopy, there are some other optical techniques which are truly surface sensitive and have found widespread use. Examples are ellipsometry (see Section 9.4.1), total internal reflection fluorescence (TIRF) [316], and surface plasmon resonance techniques [348],... 

The detection and quantification of the presence of biomolecules at the surface is based on specific interactions taking place in the evanescent field, generated by the total internal reflectance or by the surface plasmon resonance. The latter is the key transduction principle in the optical bioanalysis and biosensing area (Narayanaswamy and Wolfbeis, 2004). Launched in the early 1980s in Sweden,... 

Nucleic acid biosensors based on optical modes of detection represent another common approach for generating analytical signals based on nucleic acid hybridization. The methods discussed herein are based on methods that are suitable for the study of materials on surfaces. There are a number of different optical methods that have been described, with the most common being attenuated total reflectance (ATR), total internal reflection fluorescence (TIRF) and surface plasmon resonance (SPR) [15]. All of these methods work... 

An antibody is immobilized on the surface of a waveguide (a quartz, glass, or plastic slide, or a gold- or silver-coated prism), and binding of an antigen is measured directly by total internal reflection fluorescence, surface plasmon resonance, or attenuated total reflection. 

FOS Fiber-optic sensors PEG Photonic band gap PCF Photonic crystal fiber PCR Polymerize chain reaction SPR Surface plasmon resonance TIR Total internal reflection... 

As a consequence, researchers from different disciplines of the life sciences ask for efficient and sensitive techniques to characterize protein binding to and release from natural and artificial membranes. Native biological membranes are often substituted by artificial lipid bilayers bearing only a limifed number of components and rendering the experiment more simple, which permits the extraction of real quantitative information from binding experiments. Adsorption and desorption are characterized by rate constants that reflect the interaction potential between the protein and the membrane interface. Rate constants of adsorption and desorption can be quantified by means of sensitive optical techniques such as surface plasmon resonance spectroscopy (SPR), ellipsometry (ELL), reflection interference spectroscopy (RIfS), and total internal reflection fluorescence microscopy (TIRE), as well as acoustic/mechanical devices such as the quartz crystal microbalance (QCM)... 

Figure 7.27 Schematic illustration of Surface Plasmon Resonance (SPR). Incident light is normally subject to total internal reflection in the prism block except for losses due to evanescent wave penetration of the hydrogel layer at the resonant angle. Changes in resonant angle due to receptor-ligand interactions are the basis for the real time observation of molecular recognition and association/dissociation events.

FIGURE 21-14 Surface plasmon resonance. Laser radiation is coupled into the glass substrate coaled with a thin metal film by a half-cylindrical prism. If total internal reflection occurs, an evanescent wave is generated in the medium of lower refractive index. This wave can exciie surface plasmon waves. When the angle Is suitable for surface plasmon resonance, a sharp decrease in the reflected intensity is observed at the detector. 

X-ray photoelectron spectroscopy Surface plasmon resonance Quartz crystal microbalance Waveguide interfaometry (Spectroscopic) eUipsometry Fluorescence spectroscopy and microscopy (including immunofluorescence, total internal reflection fluorescence)... 

This chapter does not cover probe-beam deflection used for spectroscopy [22], reflection spectroscopy [23, 24], surface plasmon resonance [23], second harmonic generation [25, 26], ellipsometry (Muller in Refs. [10, 27]), internal reflection ]28], photoacoustic and photothermal spectroscopy ]29] (neither of which has enjoyed widespread application in electrochemistry), or waveguides [30-32]. 

In this chapter, electrochemical properties of ET proteins at electrode interfaces studied by spectroelectrochem-ical techniques are described. In situ spectroelectrochemical techniques at well-defined electrode surfaces are sufficiently selective and sensitive to distinguish not only steady state structures and oxidation states of adsorbed species but also dynamics of reactants, products, and intermediates at electrode surfaces on a monolayer level. The spectroelectrochemical techniques used in studies of ET proteins include IR reflection-absorption, potential-modulated UV-vis reflectance (electroreflectance), surface-enhanced Raman scattering (SERS) and surface plasmon resonance, total internal reflection fluorescence, (TIRE) and absorbance linear dichroism spectroscopies. 

Q. Xu et ah. Surface plasmon resonances of free-standing gold nanowires fabricated by nanoskiving, Angewandte Chemie International Edition, 45(22), 3631-3635 (2006). 

In the reflection mode, typically specular reflectance is measured on the electrode surface. It is anticipated that the variation of the surface structure (e.g., surface adsorption, phase transitions, etc.) will result in appreciable changes in the reflectivity properties. One can thus correlate the structural characterislics gleaned from spectroscopic measurements with electrochanical results. Figure 2.15 shows a cell assembly for internal reflection spectroelectrochemistry. Several spectroscopic techniques have been used, such as infrared, surface plasmon resonance, and X-ray based techniques (reflectivity, standing wave, etc.). Figure 2.16 depicts a cell setup for (A) infrared spectroelectrochemistry (IR-SEC) and (B) surface X-ray diffraction. 

If the internally reflecting interface is coated with a conducting material, such as a thin metal film, the p-polarized component of the evanescent wave may penetrate the metallic layer and excite surface plasmon waves. If the metal is nonmagnetic, such as a gold film, the surface plasmon wave is also p-polarized, which creates an enhanced evanescent wave. Because of the penetration of the electric field into the lower-refractive-index medium, the interaction is quite sensitive to the refractive index at the metal film surface. When the angle is suitable for surface plasmon resonance, a sharp decrease in the reflected intensity is observed, as can be seen in Figure 21-14. The resonance condition can be related to the refractive index of the metal film and can be used to measure this quantity and other properties of the surface. 

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