Biosensor optical

Feldstein MJ, Golden JP, Rowe CA et al (1999) Array biosensor optical and fluidics systems. J Biomed Microdevices 1(2) 139-153... 

Rowe-Taitt, C. A., Ligler, F. S. (2002) Evanescent wave fiber optic biosensor. Optical Biosensor Present and Future, Elsevier, Amsterdam, pp. 95-122. 

Biophotonics Optical biosensor Optical chemical sensor Label free Refractive index Sensing principles Protein DNA Vims Bacterium... 

Keywords Far Infrared THz Biosensor Optics Imaging Diagnostics... 

Specific low-temperature sensors biosensors optical sensors fabrication hotplate platforms... 

Sensors (biosensors, optical sensors, chemical sensors,gas sensors)... 

Optical biosensors based on fluorescence detection often use the combination of a fluorescent bioreceptor associated with an optical transducer. Fluorescent biosensors may also be obtained by immobilizing whole cells on the surface of a sensor layer. This bioactive layer is usually placed in front of the tip of an optical fibers bundle to generate a fluorescent signal. The optical fibers are required to send the excitation radiation to the fluorescent bioelement and convey the fluorescence radiation up to a fluo-rimeter. In order to improve the simpHcity and reliability of fluorescence-based biosensors, optically translucent supports are used because their optical properties enable detection of fluorescence emitted by the algal cells. 

Although iastmmentation is discussed ia many of the analytical articles, there are only a few places ia the Eniyclopedia where it is the primary emphasis (see Analytical methods, hyphenated instruments Automated instrumentation). However, articles relating to materials used either ia or as iastmmeatal compoaeats such as eaergy sources (see Lasers), sampling devices (see Eiber optics), and detectors (see Biosensors Photodetectors SsENSORs) abound. 

The dye is excited by light suppHed through the optical fiber (see Fiber optics), and its fluorescence monitored, also via the optical fiber. Because molecular oxygen, O2, quenches the fluorescence of the dyes employed, the iatensity of the fluorescence is related to the concentration of O2 at the surface of the optical fiber. Any glucose present ia the test solution reduces the local O2 concentration because of the immobilized enzyme resulting ia an iacrease ia fluorescence iatensity. This biosensor has a detection limit for glucose of approximately 100 ]lM , response times are on the order of a miaute. 

PSS-SG composite film was tested for sorption of heme proteins hemoglobin (Hb) and myoglobin (Mb). The peroxidaze activity of adsorbed proteins were studied and evaluated by optical and voltammetric methods. Mb-PSS-SG film on PG electrode was shown to be perspective for detection of dissolved oxygen and hydrogen peroxide by voltammetry with linear calibration in the range 2-30 p.M, and detection limit -1.5 p.M. Obtained composite films can be modified by different types of biological active compounds which is important for the development of sensitive elements of biosensors. 

Ohmic drop, 32, 88, 105, 129 Operational amplifier, 105 Optically transparent electrode, 40 Organic-phase biosensors, 181 Organic solvents, 102 Organosulfur monolayers, 118 Overvoltage, 14, 121 Oxygen, 75, 87, 103, 177, 190, 193... 

Later on, such S-layer-based sensing layers were also used in the development of optical biosensors (optodes), where the electrochemical transduction principle was replaced by an optical one [97] (Fig. 10c). In this approach an oxygen-sensitive fluorescent dye (ruthenium(II) complex) was immobilized on the S-layer in close proximity to the glucose oxidase-sensing layer [97]. The fluorescence of the Ru(II) complex is dynamically quenched by molecular oxygen. Thus, a decrease in the local oxygen pressure as a result of... 

Possible applications include optical coatings [98], catalysts [99-101], substrates for Surface Enhanced Raman spectroscopy [102] or biosensor electrodes [103], Mesoporous gold can be prepared by de-aHoying a suitable precursor such as a... 

A large number of possible applications of arrays of nanoparticles on solid surfaces is reviewed in Refs. [23,24]. They include, for example, development of new (elect-ro)catalytical systems for applications as chemical sensors, biosensors or (bio)fuel cells, preparation of optical biosensors exploiting localized plasmonic effect or surface enhanced Raman scattering, development of single electron devices and electroluminescent structures and many other applications. 

S. Sayler, Optical biosensor for environmental online monitoring of naphthalene and salicylate bioavailability with an immobilized biolumine.scent catabolic reporter bacterium. Appl. Environ. Microbiol. 60 1494 (1994). 

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