Crosslinked adduct of polyaniline and polymer acid containing redox enzyme for electrochemical sensor

• US 8,080,385 B2
• Filed: 05/02/2008
• Issued: 12/20/2011
• Est. Priority Date: 05/03/2007
• Status: Active Grant

• Current Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories Incorporated)
• Inventors: Heller, Adam, Feldman, Benjamin J., Mano, Nicolas, Loo, Yueh-Lin
• Primary Examiner(s): NAFF, DAVID M
• Application Number:
  US12/114,359
• Publication Number:
  US 20090321277A1
• Time in Patent Office: 1,327 Days
• Field of Search: None
• US Class Current: 435/14
• CPC Class Codes: C12Q 1/001 Enzyme electrodes
• CPC Class Codes: C12Q 1/005 involving specific analytes or enzymes including groups of enzymes, e.g. oxydases; C12Q1/004 takes precedence
• CPC Class Codes: C12Q 1/006 for glucose
• CPC Class Codes: C12Q 1/26 involving oxidoreductase
• CPC Class Codes: G01N 27/327 Biochemical electrodes , e.g. electrical or mechanical details for in vitro measurements
• CPC Class Codes: G01N 27/3271 Amperometric enzyme electrodes for analytes in body fluids, e.g. glucose in blood amperometry per se G01N27/49; aspects concerning the enzyme reagent C12Q1/001

Abstract

A polymer matrix that may coated on an electrode is created by co-crosslinking (1) an adduct of a polyaniline formed by templated oxidative polymerization on a polymer acid; (2) a water-soluble crosslinker; and (3) a redox enzyme. The polymer matrix may be hydrated, and the absorbed water may make it permeable to, for example, glucose. The polyaniline may be polyaniline itself or a substituted polyaniline; the water-soluble crosslinker may be poly(ethylene glycol) diglycidyl ether, and the redox enzyme may be glucose oxidase. The polymer matrix may be produced by co-crosslinking (1) an adduct of an electrically conductive polymer and a polymer acid; (2) a water-soluble crosslinker; and (3) a redox enzyme in a single step at an about neutral pH, curing by drying. After hydration, the crosslinked polymer matrix may form a 3-dimensional glucose-permeable bioelectrocatalyst, catalyzing the electrooxidation of glucose.

Claims

1. A crosslinked polymer matrix comprising:

polyaniline or a ring substituted polyaniline and poly(2-acrylamido-2-methyl-propane sulfonic acid) (PAAMSA);

a water-soluble crosslinker; and

one or more enzymes, wherein at least one of the enzymes is a redox enzyme.

2. The crosslinked polymer matrix according to claim 1, wherein the crosslinked polymer matrix is a hydrogel.

3. The crosslinked polymer matrix according to claim 2, wherein the redox enzyme is capable of catalyzing the oxidation of a substrate at an electrode.

4. The crosslinked polymer matrix according to claim 3, wherein the substrate is glucose.

5. The crosslinked polymer matrix according to claim 2, wherein the redox enzyme is capable of catalyzing the reduction of a substrate at an electrode.

6. The crosslinked polymer matrix according to claim 3, wherein the substrate is hydrogen peroxide.

7. The crosslinked polymer matrix according to claim 1, wherein the polyaniline or the ring substituted polyaniline and PAAMSA are present in a molar ratio of from about 1:

0.7 to about 1;

0.99 in the adduct.

8. The crosslinked polymer matrix according to claim 1, wherein the water-soluble crosslinker comprises poly(ethylene glycol) diglycidyl ether.

9. The crosslinked polymer matrix according to claim 1, wherein the water-soluble crosslinker is present in an amount of from about 2 weight % to about 30 weight %, based upon the dry weight of the polymer matrix.

10. The crosslinked polymer matrix according to claim 1, wherein the redox enzyme is selected from the group consisting of a flavoenzyme, a heme enzyme, and a pyrroloquinoline quinone (PQQ) enzyme.

11. The crosslinked polymer matrix according to claim 1, wherein the redox enzyme is selected from the group consisting of glucose oxidase, glucose dehydrogenase, and peroxidase.

12. The crosslinked polymer matrix according to claim 1, wherein the crosslinked polymer matrix comprises at least two enzymes, wherein a first enzyme catalyzes a reaction to form a substrate for a second enzyme, and wherein the second enzyme is a redox enzyme.

13. The crosslinked polymer matrix according to claim 1, wherein the redox enzyme is present in an amount of from greater than 0 weight % to about 60 weight %, based upon the dry weight of the polymer matrix.

14. The crosslinked polymer matrix according to claim 2, wherein the crosslinked polymer matrix is permeable to glucose.

15. An electrochemical sensor comprising:

a working electrode;

a counter electrode; and

a crosslinked polymer matrix disposed on a least a portion of the working electrode comprising;

polyaniline or a ring substituted polyaniline and PAAMSA;

a water soluble crosslinker; and

one or more enzymes, wherein at least one of the enzymes is a redox enzyme.

16. The electrochemical sensor according to claim 15, wherein the crosslinked polymer matrix is a hydrogel.

17. The electrochemical sensor according to claim 15, wherein the water-soluble crosslinker comprises poly(ethylene glycol)diglycidyl ether.

18. The electrochemical sensor according to claim 15, wherein the redox enzyme is selected from the group consisting of a flavoenzyme, a heme enzyme, and a PQQ enzyme.

19. The electrochemical sensor according to claim 15, wherein the redox enzyme is selected from the group consisting of glucose oxidase, glucose dehydrogenase, and peroxidase.

20. The electrochemical sensor according to claim 15, wherein the redox enzyme of the crosslinked polymer matrix is capable of the electrooxidation of glucose at a current density of greater than 100 μ

A cm<sup>−

2</sup> at 40 mM glucose concentration, at an electrode poised at 0.3 V vs. Ag/AgCl or less.

21. The electrochemical sensor according to claim 15, wherein the redox enzyme of the crosslinked polymer matrix has an apparent Michaelis-constant obtained from an Edi-Hofstee plot of greater than 10 mM glucose.