Enzyme biosensors amperometric biosensor

P. Mulchandani, W. Chen, and A. Mulchandani, Flow injection amperometric enzyme biosensor for direct determination of organophosphate nerve agents. Environ. Sci. Technol. 35, 2562-2565 (2001). 

Construction of enzyme-based amperometric biosensors usually involves coating the electrode surface with both the enzymes and the mediator. The method adopted and concentrations used are important factors in the performance of the device. For extended use, covalent immobilization is the most satisfactory method. 

Photoswitchable redox-enzymes 1. Amperometric transduction of optical information - biocomputers 2. Amplification of weak optical signals -photonic amplifiers 3. Multisensor arrays — biosensor and bioelectronics 4. Photoelectrochemical systems Enzyme immobilized on electronic transducer... 

Prodromidis, M.I., Karayannis, M.I. (2002). Enzyme based amperometric biosensors for food analysis. Electroanalysis 14 241-61. 

An enzyme biosensor consists of an enzyme as a biological sensing element and a transducer, which may be amperometric, potentiometric, conductimetric, optical, calorimetric, etc. Enzyme biosensors have been applied to detecting various substrates (Table 3.1), which are selectively oxidized or reduced in enzyme-catalyzed processes depending on the nature of substrates and enzymes used (oxidases or reductases) to construct sensors. 

Enzyme biosensors containing pol3mieric electron transfer systems have been studied for more than a decade. One of the earlier systems was first reported by Degani and Heller [1,2] using electron transfer relays to improve electrochemical assay of substrates. Soon after Okamoto, Skotheim, Hale and co-workers reported various flexible polymeric electron transfer systems appUed to amperometric enz5une biosensors [3-16], Heller and co-workers further developed a concept of wired amperometric enzyme electrodes [17—27] to increase sensor accuracy and stability. 

Amperometric enzyme biosensors using polyKvinylpyridinelOsObipyridinelgCl ] based hydrogels (A)... 

Amperometric enzyme biosensors using polymeric electron transfer systems... 

Amperometric enzyme biosensor for glucose Clark Jr. and Lyons3... 

Schuhmann, W. Amperometric enzyme biosensors based on optimized electron-transfer pathways and non-manual immobilization procedures. Rev. Mol. Biotechnol. 2002, 82, 425-441. 

Horozova, E., Dodevska, T., and Dimcheva, N. (2009) Modified graphites application to the development of enzyme-based amperometric biosensors. Bioelectrochemistry, 74 (2), 260-264. 

Mena, M.L.,Yanez-Sedeno, P., Pingarron, J.M. (2005) A comparison of different strategies for the construction of amperometric enzyme biosensors using gold nanoparticle-modified electrodes. Anal. Biochem., 336, 20-27... 

Since hydrogen peroxide is the product of reactions catalysed by a huge number of oxidase enzymes and is essential in food, pharmaceutical, and envitonmental analysis, its detection was and remains a necessity. Many attempts have been made in order to develop a biosensor that would be sensitive, stable, inexpensive and easy to handle. The most popular and efficient of them are amperometric enzyme biosensors, which utihsed different types of mediators and enzymes, mosdy peroxidase and catalase. Unfortunately many of the sensors developed do not mea the requirements for a practical device, which has a balance of technological charaaeristics (sensitivity, reliability, stability) and commercial adaptability (easy of mass production and low price). Thus a window of opportunity still remains open for future development. We hope that the present work will inspire other researches for further advances in the area of biosensors, in particular sensors for detection of such an important analyte as hydrogen peroxide. 

X. Luo, G. D. Vidal, A. J. Killard, A. Morrin, and M. R. Sm3dh, Nanocauliflowers A nanostructured polyaniUne-modified screen-printed electrode with a self-assembled polystyrene template and its application in an amperometric enzyme biosensor, Electroanalysis, 19, 876-883 (2007). 

Morrin, A., O. Ngamna, A.J. Killard, S.E. Moulton, M.R. Smyth, and G.G. Wallace. 2005. An amperometric enzyme biosensor fabricated from polyaniline nanoparticles. Electroanalysis 17 423. 

Brahim, S., D. Narinesingh, and A. Guiseppi-Elie. 2002. Interferent suppression using a novel polypyrrole-containing hydrogel in amperometric enzyme biosensors. Electroanalysis 14 (9) 627. 

H2O2 over a wide pH range demonstrates its applicability in construction of oxidase enzyme-based amperometric biosensors. 

Dinitrotoluene Chemical warfare agents Chloro-bispropyl ethers Custom vapor sampler Sensory polymers attached to fiber optics Flow injection amperometric enzyme biosensor Enantioselective GC-MS... 

Ghica, M.E., Pauliukaite, R., Fatibello-FiUio, O., Brett, C.M.A. Application of functionalised carbon nanotubes immobilised into chitosan films in amperometric enzyme biosensors. Sens. Actuat. B 142, 308-315 (2009)... 

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