THIN-FILM CONDUCTIMETRIC SENSORS FOR ENZYME BIOTRANSDUCERS

Characteristics of thin-film conductimetric Au, Ni, Cu, and Cr sensors are studied. Physicochemical processes occurring at the metal-electro lyte interface and in the bulk of an electrolyte are represented by an equivalent electrical circuit. Its validity is confirmed experimental ly. To chose proper working conditions for thin-film conductimetric se nsors, ac impedance spectroscopy is used. The effects of the solution background conductivity, temperature, and time necessary to store the sensors in a buffer on the impedance curves are studied. It is shown t hat these sensors can be used as enzyme biosensors except for Cr elect rodes, which possess intrinsic resistivity that is too high.