Lyotropic liquid crystal coated analyte monitoring device and methods of use

• US 8,255,034 B2
• Filed: 11/30/2007
• Issued: 08/28/2012
• Est. Priority Date: 11/30/2006
• Status: Expired due to Fees

• Current Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories)
• Original Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories)
• Inventors: Heller, Adam, Rowinski, Pawel, Feldman, Benjamin J.
• Primary Examiner(s): Mallari, Patricia
• Assistant Examiner(s): CATINA, MICHAEL ANTHONY
• Application Number:
  US11/948,915
• Publication Number:
  US 20080177164A1
• Time in Patent Office: 1,733 Days
• Field of Search: 600345-347, 600/365, 435/4, 422/50, 20440301-40315
• US Class Current: 600/347
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1468 using chemical or electrochemical methods, e.g. by polarographic means A61B5/1486 takes precedence
• CPC Class Codes: A61B 5/14865 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors
• CPC Class Codes: C12Q 1/006 for glucose
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing

Abstract

The present invention is directed to membranes composed liquid crystals having continuous aqueous channels, such as a lyotropic liquid crystal, including a cubic phase lyotropic liquid crystal, and to electrochemical sensors equipped with such membranes. The membranes are useful in limiting the diffusion of an analyte to a working electrode in an electrochemical sensor so that the sensor does not saturate and/or remains linearly responsive over a large range of analyte concentrations. Electrochemical sensors equipped with membranes of the present invention demonstrate considerable sensitivity and stability, and a large signal-to-noise ratio, in a variety of conditions.

Claims

1. An electrochemical analyte sensor for determining the concentration of an analyte, comprising:

a working electrode comprising;

a sensing layer comprising an analyte-responsive enzyme and a redox mediator in contact with the electrode;

a non-crosslinked cubic phase lyotropic liquid crystal membrane disposed on top of the sensing layer, and

a counter or a reference or a counter/reference electrode in electrochemical communication with the working electrode.

2. The electrochemical sensor of claim 1, wherein the analyte-responsive enzyme is a glucose-responsive enzyme.

3. The electrochemical sensor of claim 2, wherein the glucose-responsive enzyme is a wired enzyme.

4. The electrochemical sensor of claim 2, wherein the glucose-responsive enzyme is a glucose-dehydrogenase.

5. The electrochemical sensor of claim 4, wherein the glucose-dehydrogenase is an FAD-dependent glucose dehydrogenase.

6. The electrochemical sensor of claim 4, wherein the glucose-dehydrogenase is glucose oxidase.

7. The electrochemical sensor of claim 1, wherein the redox mediator comprises a ruthenium-containing complex and/or an osmium-containing complex.

8. The electrochemical sensor of claim 1, wherein the cubic phase lyotropic liquid crystal is substantially non-hydrolyzable in the presence of a lipase.

9. The electrochemical sensor of claim 1, wherein the cubic phase lyotropic liquid crystal comprises a compound of the formula:

10. The electrochemical sensor of claim 9, wherein the cubic phase lyotropic liquid crystal comprises Vitamin E acetate.

11. The electrochemical sensor of claim 1, wherein the sensor is adapted so that at least a portion of the sensor is positionable beneath the skin of a user.

12. The electrochemical sensor of claim 1, wherein the sensor comprises an anticlotting agent.

13. The electrochemical sensor of claim 12, wherein the anticlotting agent is heparin.

14. The electrochemical sensor of claim 12, wherein the cubic phase lyotropic liquid crystal comprises the anticlotting agent.

15. The electrochemical sensor of claim 1, wherein the cubic phase lyotropic liquid crystal membrane is adapted to limit the flux of glucose or lactate thereacross.

16. The electrochemical sensor of claim 1, wherein the analyte is glucose.

31. The electrochemical sensor of claim 1, wherein the cubic phase lyotropic liquid crystal is non-polymeric.

33. The electrochemical sensor of claim 1, wherein the cubic phase lyotropic liquid crystal is isotropic.

35. The electrochemical sensor of claim 1, wherein the cubic phase lyotropic liquid crystal comprises a link between a polar head and a hydrocarbon tail other than an ester.

37. The electrochemical sensor of claim 35, wherein the link between a polar head and hydrocarbon tail is an ether linkage.

17. An electrode for use in a biosensor for determining the concentration of an analyte, comprising:

a sensing layer comprising an analyte-responsive enzyme and a redox mediator in contact with the electrode, and

a non-crosslinked cubic phase lyotropic liquid crystal membrane disposed on top of the sensing layer.

18. The electrode of claim 17, wherein the analyte-responsive enzyme is a glucose-responsive enzyme.

19. The electrode of claim 17, wherein the redox mediator comprises a complex selected from the group consisting of a ruthenium-containing complex and an osmium-containing complex.

20. The electrode of claim 18, wherein the glucose-responsive enzyme is a wired enzyme.

21. The electrode of claim 18, wherein the glucose-responsive enzyme is a glucose-dehydrogenase.

22. The electrode of claim 21, wherein the glucose-dehydrogenase is an FAD-dependent glucose dehydrogenase.

23. The electrode of claim 21, wherein the glucose-dehydrogenase is glucose oxidase.

24. The electrode of claim 17, wherein the redox mediator comprises a ruthenium containing complex and/or an osmium-containing complex.

25. The electrode of claim 17, wherein the cubic phase lyotropic liquid crystal is substantially non-hydrolyzable in the presence of a lipase.

26. The electrode of claim 17, wherein the cubic phase lyotropic liquid crystal comprises a compound of the formula:

27. The electrode of claim 26, wherein the cubic phase lyotropic liquid crystal comprises Vitamin E acetate.

28. The electrode of claim 17, wherein the cubic phase lyotropic liquid crystal membrane is adapted to limit the flux of glucose or lactate thereacross.

29. The electrode of claim 17, wherein the cubic phase lyotropic liquid crystal membrane is adapted to limit the flux of glucose or lactate thereacross in vivo.

30. The electrode of claim 17, wherein the sensing layer comprises an anticlotting agent such as heparin.

32. The electrode of claim 17, wherein the cubic phase lyotropic liquid crystal is non-polymeric.

34. The electrode of claim 17, wherein the cubic phase lyotropic liquid crystal is isotropic.

36. The electrode of claim 17, wherein the cubic phase lyotropic liquid crystal comprises a link between a polar head and a hydrocarbon tail other than an ester.

38. The electrode of claim 36, wherein the link between a polar head and hydrocarbon tail is an ether linkage.