| Abstract: | A microfabricated capacitive chemical sensor can be used as an autonomous
chemical sensor or as an analyte-sensitive chemical preconcentrator in a
larger microanalytical system. The capacitive chemical sensor detects
changes in sensing film dielectric properties, such as the dielectric
constant, conductivity, or dimensionality. These changes result from the
interaction of a target analyte with the sensing film. This capability
provides a low-power, self-heating chemical sensor suitable for remote
and unattended sensing applications. The capacitive chemical sensor also
enables a smart, analyte-sensitive chemical preconcentrator. After
sorption of the sample by the sensing film, the film can be rapidly
heated to release the sample for further analysis. Therefore, the
capacitive chemical sensor can optimize the sample collection time prior
to release to enable the rapid and accurate analysis of analytes by a
microanalytical system. |