Abstract: Electrically conducting homo- and/or copolymers and/or tripolymers can be produced from novel monomers, such as a 3-substituted 2,5-di(2-thienyl)pyrrole. The polymers exhibit unexpectedly high stability and conductivities, and can be functionalized, such as with an enzyme, like glucose oxidase, or an ion-specific binding site, like a crown ether, or an antigen, without adversely affecting the conductivity of the polymer. The functionalized, conducting polymer can be used in a diagnostic device to determine the presence and concentration of a specific analyte in a liquid medium.