Alexander J Yacynych

US Patent:

55408281, Jul 30, 1996

Filed:

Feb 15, 1994

Appl. No.:

8/196838

Inventors:

Alexander Yacynych - East Brunswick NJ

International Classification:

G01N 2726

US Classification:

204418

Abstract:

A method for making a sensing element for use in a sensor or biosensor that amperometrically measures the concentration of an analyte in a liquid, includes the following sequential steps: a) obtaining an electrode; b) immersing the electrode in a solution of monomer that is capable of being electropolymerized into an electrically insulating polymer; c) flowing an electric current from a cathode through the solution to the electrode at a voltage and amperage sufficient to cause the monomer to polymerize on the surface of the electrode, thereby yielding an electrode coated with an adherent layer of electrically insulating polymer; and e) impregnating the polymeric coating on the surface with a sensing agent that is capable, when contacted by a specific analyte in a chemical or biological liquid, of generating an electroactive molecule that can be detected amperometrically.

US Patent:

52863646, Feb 15, 1994

Filed:

Mar 29, 1991

Appl. No.:

7/677384

Inventors:

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

Assignee:

Rutgers University - New Brunswick NJ

International Classification:

G01N 2726

US Classification:

204418

Abstract:

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.