Applied biosensors

Utilization of enzyme-substrate interactions in analytical chemistry

Enzymes are capable of a highly specific interaction with a variety of substances including their respective substrates. This review summarizes how such interactions may be used in analytical (bio-)chemistry, e.g., for the elucidation of the binding mechanism, the determination of the binding strength, the carting of the binding site, or the screening of possible substrate/inhibitor molecules. Possible assay formats such as analytical affinity chromatography, affinity capillary electrophoresis (ACE), conventional affinity gel electrophoresis (AEP), and related techniques are discussed together with examples of recent applications. In addition a brief section on enzyme-substrate reactions as tools in analytical chemistry is included, since these are perhaps even more important to analytical (bio-)chemistry. The development and application of bioanalytical systems and especially biosensors in various fields including medicine, biotechnology, agriculture, defense and foodstuffs are considered.

Biosensors

Advances in biosensor technology over the past year have included developments in metalized electrodes, mediated electrochemistry, direct electron transfer, impedance measurement, optical immunosensors, optodes, biomimicry, piezoelectric biosensors, enzyme thermistors, in vivo biosensors, surface characterization, organic-phase biosensors and tissue-based biosensors. Increasingly, molecular biology and engineering are being used in sensor design.

Immobilized cells used for detection and analysis

Many kinds of biosensor have now been developed and utilized for various types of analysis including clinical, medical and environmental monitoring, industrial process control, as well as many other applications. The microbial biosensor has advantages, such as longer lifetime and lower cost, over other types of biosensor. Recently, photobacteria and recombinant bacteria have been employed in biosensors both for determining biochemical oxygen demand and for detecting heavy metals and other toxic compounds.