Enzyme-based sensors, technological

Chapters 1 to 5 deal with ionophore-based potentiometric sensors or ion-selective electrodes (ISEs). Chapters 6 to 11 cover voltammetric sensors and biosensors and their various applications. The third section (Chapter 12) is dedicated to gas analysis. Chapters 13 to 17 deal with enzyme based sensors. Chapters 18 to 22 are dedicated to immuno-sensors and genosensors. Chapters 23 to 29 cover thick and thin film based sensors and the final section (Chapters 30 to 38) is focused on novel trends in electrochemical sensor technologies based on electronic tongues, micro and nanotechnologies, nanomaterials, etc. 

In the last decade, a rapid technological evolution took place in the field of chemical sensors in general, and enzyme based sensors in particular (7). This progress has been at least partly due to the commercial interest in sensor technology for diagnostic medicine, both for real-time analysis of metabolites in metabolically unstable patients and rapid bed-side monitoring (2-J). 

Biosensors based on enzyme inhibition are still limited in analytical applications since these sensor technologies are not usually able to discriminate various toxic compounds in the same sample. 

Measuring and testing sensor technology, as well as vision inspection systems Enzyme-based biosensor system for monitoring the freshness of fish... 

Sample Handling. Enzymes Immobilized Enzymes Enzyme-Based Assays. Fluorescence Clinical and Drug Applications. Gas Chromatography Mass Spectrometry. Infrared Spectroscopy Near-Infrared. Isotope Dilution Analysis. Liquid Chromatography Column Technology Instrumentation. Sensors Overview. 

See also Electrophoresis Two-Dimensional Gels Nucleic Acids. Enzymes Enzyme-Based Assays. Flow Injection Analysis Principles. Fluorescence Quantitative Analysis. Lab-on-a-Chip Technologies. Mass Spectrometry Matrix-Assisted Laser Desorption/loniza-tion Time-of-Flight. Microelectrodes. Microscopy Overview. pH. Process Analysis Overview Chromatography Electroanalytical Techniques Sensors Acoustic Emission Maintenance, Reliability, and Training. Proteins Overview. Proteomics. Purines, Pyrimidines, and Nucleotides. Sensors Oven/iew. Spectrophotometry Overview. 

Overall, the implementation of lanthanide probes in chemical sensor technology is still in its initial stage. Up to now they have not found their way into commercialized sensor systems. Particularly, with respect to p02 and pH sensors, it cannot be foreseen that LLCs may displace established fluorescent indicators. Sensors for small molecules such as hydrogen peroxide, phosphate, or ATP can be useful in enzymatic assays in which the conversion of the substrate has to be monitored. In this case, the selectivity is provided by the enzyme involved. A concrete example is presented by means of a glucose sensor based on immobilized glucose oxidase and... 

Based on many of the advances described above in electrochemical approaches to immunoassay, it is tempting to conclude that commercialization of some of the approaches is imminent. This may be true, but the historical use of optical methods for many clinical chemistry tests coupled with their rapidly growing use in immunoassay is a difficult barrier for any radically different method to overcome, though electrochemical sensors have become more important in the clinical chemistry laboratory over the last decade. In any event, to be successful ECIA methods will have to demonstrate clear superiority over existing and emerging technologies in both cost and performance. Some of the more recently described approaches such as those using enzyme amplified amperometric detection and ecLIA appear... 

B. Feldman, R. Brazg, S. Schwartz, and R. Weinstein, A continuous glucose sensor based on wired enzyme technology. Diabetes Tech. Ther. 5, 769-779 (2003). 

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