Amperometric sensor

• US 7,135,100 B1
• Filed: 06/29/2000
• Issued: 11/14/2006
• Est. Priority Date: 06/29/1999
• Status: Expired due to Fees

• Current Assignee: Drew Scientific Holdings, Inc.
• Original Assignee: Drew Scientific Ventures LLC
• Inventors: Slater, Jonathan Mark, Lau, Kim King Tong
• Primary Examiner(s): NOGUEROLA, ALEXANDER STEPHAN
• Application Number:
  US10/019,220
• Time in Patent Office: 2,329 Days
• Field of Search: 204/403.04, 204/403.09, 204/403.1, 204/403.11, 204/403.14, 204/403.12, 204416-418, 205/782
• US Class Current: 204/403.14
• CPC Class Codes: C01B 15/01 Hydrogen peroxide
• CPC Class Codes: C01C 3/12 Simple or complex iron cyanides
• CPC Class Codes: C07C 211/63 having quaternised nitrogen atoms bound to acyclic carbon atoms
• CPC Class Codes: C12Q 1/004 mediator-assisted
• CPC Class Codes: C12Q 1/006 for glucose
• 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

An amperometric sensor suitable for determining the concentration of hydrogen peroxide in a sample, said sensor comprising a ferricyanide compound which, in reduced form, functions as a mediator specific to hydrogen peroxide.

Claims

1. An amperometric sensor suitable for determining the concentration of hydrogen peroxide in a sample, said sensor comprising a ferricyanide compound which, in reduced form, functions as a mediator selective for hydrogen peroxide, wherein the ferricyanide compound is of general formula:

X₃Fe(CN)₆

wherein each X is a phosphonium ion of formula (R⁵)(R⁶)(R⁷)(R⁸)P⁺ in which R⁵ to R⁸ are the same or different alkyl groups containing from 1 to 20 carbon atoms, provided that at least one group R⁵ to R⁸ contains at least 4 carbon atoms.

2. A sensor according to claim 1, further comprising an enzyme which is capable of reacting with an analyte in the sample to produce hydrogen peroxide.

3. A sensor according to claim 2, wherein the analyte is glucose and the enzyme is glucose oxidase.

4. A sensor according to claim 1, in which the ferricyanide compound is bound to a polymer.

5. A sensor according to claim 4, wherein the polymer is a polyacrylamide.

6. A sensor according to claim 4, wherein the ferricyanide compound is bound to the polymer via one of groups R⁵ to R⁸ of a quaternary phosphonium ion of formula

(R⁵)(R⁶)(R⁷)(R⁸)P⁺.

7. A sensor according to claim 1, wherein the ferricyanide compound has a solubility of from 2000 mg/L to 20,000 mg/L in pure water.

8. A sensor according to claim 7, wherein the ferricyanide compound is polypyridinium ammonium ferricyanide of poly(acrylamide-co-diethyldimethyl ammonium)ferricyanide.

9. A cartridge for an amperometric sensor suitable for measuring hydrogen peroxide in a sample, which cartridge comprises a ferricyanide compound as defined in claim 1.

10. A cartridge according to claim 9, further comprising an enzyme which is capable of reacting with an analyte in the sample to produce hydrogen peroxide.

11. A cartridge according to claim 10, wherein the enzyme is glucose oxidase.

12. An amperometric sensor suitable for determining the concentration of hydrogen peroxide in a sample, said sensor comprising a ferricyanide compound bound to a polymer, which ferricyanide, in reduced form, functions as a mediator selective for hydrogen peroxide, wherein the ferricyanide compound is a ferricyanide compound having a solubility of from 2000 mg/L to 20,000 mg/L in pure water.

13. A sensor according to claim 12, wherein the polymer is a polyacrylamide.

14. A sensor according to claim 12, further comprising an enzyme which is capable of reacting with an analyte in the sample to produce hydrogen peroxide.

15. A sensor according to claim 14, wherein the analyte is glucose and the enzyme is glucose oxidase.

16. A sensor according to claim 12, wherein the ferricyanide compound is of general formula:

X₃Fe(CN)₆

in which the groups X are the same or different and at least one X is a non-metallic ion.

17. A sensor according to claim 16, in which each X is a quaternary ammonium ion of formula (R¹)(R²)(R³)(R⁴)N⁺ in which R¹ to R⁴ are the same or different alkyl groups containing from 1 to 20 carbon atoms, provided that at least one of R¹ to R⁴ contains at least 4 carbon atoms.

18. A sensor according to claim 17, wherein the ferricyanide compound is tetrahexylammonium ferricyanide, tetrakisdecylammonium ferricyanide, tetradecyltrimethylammonium ferricyanide, hexadecyltrimethylammonium ferricyanide or trimethyhexylammonium ferricyanide.

19. A sensor according to claim 16, wherein each X is a phosphonium ion of formula (R⁵)(R⁶)(R⁷)(R⁸)P⁺ in which R⁵ to R⁸ are the same or different alkyl groups containing from 1 to 20 carbon atoms, provided that at least one group R⁵ to R⁸ contains at least 4 carbon atoms.

20. A sensor according to claim 16, wherein each X is a nitrogen-containing heterocylic cation.

21. A sensor according to claim 20, wherein each X is a pyridinium ion.

22. A sensor according to claim 12, wherein the ferricyanide compound is bound to the polymer via one of groups R¹ to R⁴ of a quaternary ammonium ion of formula

(R¹)(R²)(R³)(R⁴)N⁺

or via one of groups R⁵ to R⁸ of a quaternary phosphonimum ion of formula

(R⁵)(R⁶)(R⁷)(R⁸)P⁺

or via a nitrogen-containing heterocyclic cation.

23. A cartridge for an amperometric sensor suitable for measuring hydrogen peroxide in a sample, which cartridge comprises a ferricyanide compound as defined in claim 12.

24. A cartridge to claim 23, further comprising an enzyme which is capable of reacting with an analyte in the sample to produce hydrogen peroxide.

25. A cartridge according to claim 24, wherein the enzyme is glucose oxidase.