| 摘要 |
Chemical and biological sensors are provided that convert the chemical potential energy of an analyte into a proportionate electrical signal through the transducer action of a microfabricated device with an integral electroconductive polymer film. The microsensor devices possess a coplanar arrangement of at least one, and typically three, microfabricated interdigitated microsensor electrode arrays each with line and space dimensions that may range from 2-20 mu m and is typically 10 mu m, a platinized platinum counter electrode of area at least 10 times the area of the interdigitated microsensor electrode array and a chloridized silver/silver chloride reference electrode. Chemical and biological sensors constructed according to the present invention employ a thin electrically conducting polymer film that is specifically attached via covalent bond formation to the interdigitated microsensor electrode component of the devices. The electrically conducting polymer film is formed in three layers, the first layer possesses high electrical conductivity and is covalently attached to the device surface, the second layer possess an inorganic catalyst and is covalently attached to the first, and the third layer possesses an indicator molecule which may be a bioactive molecule such as an enzyme or member of specific binding pair of biological origin and is itself covalently attached to the second layer. Binding of an analyte or member of the specific binding pair reagent may result in a change in the electrical impedance (resistance and capacitance or both) of the highly electrically conducting layer. The electrical change in the polymer layers is a sensitive measure of the extent of binding of the binding agent and forms an analytical signal for the binding agent.
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