Modification of Microelectrode Arrays: New Microelectrochemical Devices for Sensor Applications.

摘要

Microelectrode arrays consisting of two or eight closely spaced (approx. 1 micrometer) Au or Pt microelectrodes (approx. 2 micrometers wide x approx. 50 micrometers long x 0.1 micrometer high) can be modified with a variety of redox active materials in a way that leads to microelectrochemical devices that may be useful as sensors. In general, a pair of microelectrodes connected by a redox active material represents a device, because the current, I sub D, passing from one microelectrode (source) to the other (drain) at a fixed potential between them V sub D, can be modulated by electrically- or chemically-induced changes in the state of charge of the redox material. The fundamental issues associated with pH-sensitive devices based on poly(3-methylthiophene), poly(4-vinylpyridine), a viologen-quinone redox polymer, and WO3 are described to illustrate generic concepts that underlie the development of microelectrochemical sensors.