Mediator stabilized reagent compositions for use in biosensor electrodes

• US 8,163,146 B2
• Filed: 10/12/2007
• Issued: 04/24/2012
• Est. Priority Date: 10/12/2007
• Status: Expired due to Fees

• Current Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories)
• Original Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories)
• Inventors: Forrow, Nigel J.
• Primary Examiner(s): Olsen, Kaj K
• Assistant Examiner(s): LEONG, SUSAN DANG
• Application Number:
  US11/871,826
• Publication Number:
  US 20090095625A1
• Time in Patent Office: 1,656 Days
• Field of Search: 20440301-40315, 204/280, 205/777.5, 205/778, 205/792, 435 4- 4052, 4351734-1736, 435/183, 435/190, 4352871-2887, 436 62- 71, 436500-548
• US Class Current: 204/403.01
• CPC Class Codes: C12Q 1/004 mediator-assisted
• CPC Class Codes: C12Q 1/006 for glucose

Abstract

The claimed subject matter relates to the stabilization of 1,2-quinone mediators, especially those containing 1,10-phenanthroline quinone (PQ) and more especially transition metal complexes of PQ, in the presence of enzymes when contained in dry reagent layers for biosensor electrodes, through the use of various metal salts, particularly those of lithium.

Claims

1. A composition for use in stabilizing a biosensor, comprising:

a. an enzyme and a co-factor, and

b. a redox mediator complex comprising;

i. a first metal ion covalently bonded to at least one compound comprising a 1,2-quinone moiety; and

ii. a second metal ion non-covalently bonded to oxygen atoms of the 1,2-quinone moiety.

2. The composition of claim 1, wherein the first metal ion is selected from the group consisting of nickel, manganese, iron, cobalt, osmium, or ruthenium.

3. The composition of claim 1, wherein the ratio of the second metal ion to redox mediator complex is at least 1:

1.

4. The composition of claim 1, wherein the at least one compound comprising a 1,2-quinone moiety is 1,10-phenanthroline quinone, or a derivative thereof.

5. The method of claim 1, wherein the enzyme is selected from the group consisting of an NAD(P)+-dependent dehydrogenase, a PQQ-glucose dehydrogenase, an FAD-glucose dehydrogenase and a glucose oxidase.

6. The method of claim 5, wherein the NAD(P)+-dependent dehydrogenase is glucose hydrogenase or hydroxybutyrate dehydrogenase.

7. The composition of claim 1 wherein the redox mediator complex comprises [Ni(PQ)₃]²⁺.

8. A method for stabilizing a redox mediator complex, comprising:

adding a first metal ion to a redox mediator complex, wherein the redox mediator complex comprises a second metal ion covalently bonded to at least one compound comprising a 1,2-quinone moiety and wherein the added first metal ion non-covalently bonds to oxygen atoms of the 1,2-quinone moiety.

9. The method of claim 8, wherein the first metal ion is selected from the group consisting of lithium, scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium.

10. The method of claim 8, wherein the second metal ion is selected from the group consisting of nickel, manganese, iron, cobalt, osmium, or ruthenium.

11. The method of claim 8, wherein the ratio of first metal ion to redox mediator complex is at least 1:

1.

12. The method of claim 8 wherein the redox mediator complex comprises [Ni(PQ)₃]²⁺.

13. A biosensor strip comprising:

a. an electrode support;

b. a first electrode disposed on the electrode support, the first electrode being a working electrode,

c. a second electrode disposed on the electrode support, the second electrode being a reference electrode; and

d. a reagent composition deposited over the first electrode and second electrode, wherein the reagent composition comprises;

i. an enzyme, and

ii. a redox mediator complex comprising;

a) a first metal ion covalently bonded to at least one compound comprising a 1,2-quinone moiety; and

b) a second metal ion non-covalently bonded to oxygen atoms of the 1,2-quinone moiety.

14. The biosensor strip of claim 13, wherein the second metal ion is selected from the group consisting of lithium, scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium, but not sodium, potassium, rubidium, cesium, all other transition metals or a quaternary ammonium counter ion.

15. The biosensor strip of claim 13 wherein the redox mediator complex comprises [Ni(PQ)₃]²⁺.

16. An analyte test kit comprising:

a. a meter for measuring the concentration of an analyte, and

b. a biosensor strip, further comprising;

i. an electrode support;

ii. a first electrode disposed on the electrode support, the first electrode being a working electrode;

iii. a second electrode disposed on the electrode support, the second electrode being a reference electrode; and

iv. a reagent composition deposited over the first electrode and second electrode, wherein the reagent composition comprises;

a) an enzyme, and

b) a redox mediator complex comprising;

i) a first metal ion covalently bonded to at least one compound comprising a 1,2-quinone moiety; and

ii) a second metal ion non-covalently bonded to oxygen atoms of the 1,2-quinone moiety.

17. The analyte test kit of claim 16 wherein the redox mediator complex comprises [Ni(PQ)₃]²⁺.