Robert J Geise

52863646, Feb 15, 1994

Mar 29, 1991

7/677384

Alexander M. Yacynych - East Brunswick NJ
Sylvia S. Piznik - Jackson NJ
Eugene R. Reynolds - Highland Park NJ
Robert J. Geise - Piscataway NJ

Rutgers University - New Brunswick NJ

G01N 2726

204418

An electrode for a biosensor (e. g. , a glucose biosensor) has a layer of an electrically insulating polymer formed in situ on its operating surface by electropolymerization. For example, a diaminobenzene and a dihydroxybenzene (e. g. , 1,3-diaminobenzene and resorcinol) are copolymerized on the electrode's surface by immersing the electrode in a circulating dilute solution of the monomers in deaerated phosphate buffer, and applying a small, continuously cycling voltage between that electrode and another electrode (e. g. , from 0. 00 V to 0. 80 V) until current flow between the electrodes decreases to a minimum. Because the polymer is electrically insulating, polymerization ceases while the polymer layer is still very thin (e. g. , 10 nm). An analyte sensing agent, e. g. , an enzyme such as immobilized glucose oxidase, is imbedded in the polymer, but with a number of its analyte recognition sites unblocked.