Mediator-modified redox biomolecules for use in electrochemical determination of analyte

• US 7,807,835 B2
• Filed: 03/27/2009
• Issued: 10/05/2010
• Est. Priority Date: 07/28/2004
• Status: Expired due to Fees

• Current Assignee: Agency For Science Technology and Research
• Original Assignee: Agency For Science Technology and Research
• Inventors: Xie, Hong, Gao, Zhiqiang
• Primary Examiner(s): AULAKH, CHARANJIT
• Application Number:
  US12/413,214
• Publication Number:
  US 20090218236A1
• Time in Patent Office: 557 Days
• Field of Search: 546/10, 435/25, 435/14, 435/7.5, 435/6
• US Class Current: 546/10
• CPC Class Codes: C07F 15/0026 without a metal-carbon linkage

Abstract

Compositions and methods for electrochemical detection of an analyte comprising a transition metal compound

• • wherein M is a metallic element that can form a coordinate bond to nitrogen; R and R′ are coordinated to M at their nitrogen atoms; L is a linking ligand; Z is chlorine or bromine; m can be from 1 to 6 and X is an anion, or combination of anions, that balances the charge m. Also provided are electrochemical tags and methods of detection.

Claims

1. A transition metal compound of the formula:

2. The transition metal compound of claim 1, wherein M is selected from the group consisting of osmium, ruthenium, zinc, iron, rhodium, rhenium, platinum, scandium, titanium, vanadium, cadmium, magnesium, copper, cobalt, palladium, chromium, manganese, nickel, molybdenum, tungsten and iridium, or mixtures thereof.

3. The transition metal compound of claim 2, wherein M is osmium.

4. The transition metal compound of claim 1, wherein Z is chloro or bromo.

5. The transition metal compound of claim 1, wherein R and R′

are 1,10-phenanthrolinyl;

M is osmium;

Z is chloro; and

n is 3.

6. A method for preparing a transition metal compound, comprising contacting a precursor compound with a linking ligand to form a transition metal compound of claim 1, wherein the precursor compound has the formula:

7. The method of claim 6, wherein M is osmium.

8. The method of claim 6, wherein Z is chloro or bromo.

9. The method of claim 6, wherein R and R′

are 1,10-phenanthrolinyl;

M is osmium;

m is +3;

Z is chloro; and

the linking ligand is 3-aminopropylimidazole.

10. An electrochemical tag comprising a redox biomolecule bonded to a transition metal compound of the formula:

11. The electrochemical tag of claim 10, wherein the redox biomolecule comprises an oxidoreductase.

12. The electrochemical tag of claim 11, wherein the oxidoreductase comprises glucose oxidase.

13. The electrochemical tag of claim 10, wherein M is osmium.

14. The electrochemical tag of claim 10, wherein Z is chloro or bromo.

15. The electrochemical tag of claim 10, wherein R and R′

are 1,10-phenanthrolinyl;

M is osmium;

Z is chloro;

n is 3; and

the redox biomolecule comprises glucose oxidase.

16. A method for preparing an electrochemical tag of claim 10, comprising bonding a redox biomolecule to a transition metal compound of the formula:

17. The method of claim 16, wherein the redox biomolecule comprises an oxidoreductase.

18. The method of claim 17, wherein the oxidoreductase comprises glucose oxidase.

19. The method of claim 16, wherein the redox biomolecule is bound to the transition metal compound by an amide bond.

20. The method of claim 16, wherein M is osmium.

21. The method of claim 16, wherein Z is chloro or bromo.

22. The method of claim 16, wherein R and R′

are 1,10-phenanthrolinyl;

M is osmium;

Z is chloro;

n is 3; and

the redox biomolecule comprises glucose oxidase.

23. The method of claim 22, wherein the redox biomolecule is bound to the transition metal compound by an amide bond.

24. An electrochemical method for detecting an analyte in a sample, comprising:

forming at an electrode surface an electrochemically active redox complex comprising the analyte and an electrochemical tag; and

detecting electron transfer at the electrode,

wherein the electrochemical tag comprises a redox biomolecule bonded to a transition metal compound of the formula;

25. The method of claim 24, wherein the analyte is an oxidation substrate for the redox biomolecule.

26. The method of claim 24, wherein the redox biomolecule comprises an oxidoreductase.

27. The method of claim 26, wherein the oxidoreductase comprises glucose oxidase.

28. The method of claim 24, wherein M is osmium.

29. The method of claim 24, wherein Z is chloro or bromo.

30. The method of claim 24, wherein R and R′

are 1,10-phenanthrolinyl;

M is osmium;

Z is chloro; and

n is 3.

31. The method of claim 24, wherein the method further comprises:

immobilizing a probe onto the electrode surface;

labeling the analyte with a first member of a recognition pair;

labeling the electrochemical tag with a second member of the recognition pair; and

combining the labeled components with an oxidation substrate of the redox biomolecule in solution in contact with the electrode, wherein the probe and analyte specifically bind or hybridize to each other.

32. The method of claim 31 wherein the recognition pair comprises biotin and avidin.

33. The method of claim 31, wherein the analyte comprises a nucleic acid.

34. The method of claim 24, wherein the method further comprises:

labeling the electrode surface with a first member of a recognition pair;

labeling the electrochemical tag with a second member of the recognition pair; and

combining the labeled components with an oxidation substrate of the redox biomolecule in solution in contact with the electrode, wherein the electrochemical tag binds to the electrode surface.

35. The method of claim 34, wherein the recognition pair comprises biotin and avidin.

36. The method of claim 35, wherein the analyte comprises the substrate of the redox biomolecule.