Biosensor

• US 7,998,338 B2
• Filed: 07/17/2007
• Issued: 08/16/2011
• Est. Priority Date: 05/30/2003
• Status: Active Grant

• Current Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Abbott Laboratories Incorporated
• Inventors: McTigue, Catherine Ann, Zhang, Xiang Cheng, Forrow, Nigel John
• Primary Examiner(s): NOGUEROLA, ALEXANDER STEPHAN
• Application Number:
  US11/779,072
• Publication Number:
  US 20080245665A1
• Time in Patent Office: 1,491 Days
• Field of Search: 20440301-40315, 205/775, 205/778, 205/792
• US Class Current: 205/778
• CPC Class Codes: C12Q 1/001 Enzyme electrodes
• CPC Class Codes: G01N 33/5438 Electrodes
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor

Abstract

A biosensor for determining the concentration of an analyte in a biological sample. The biosensor comprises a support, a reference electrode or a counter electrode or both disposed on the support, a working electrode disposed on the support, the working electrode spaced apart from the other electrode or electrodes on the support, a covering layer defining a sample chamber over the electrodes, an aperture in the covering layer for receiving a sample, and at least one layer of mesh in the sample chamber between the covering layer and the electrodes. The at least one layer of mesh has coated thereon a silicone surfactant. Certain silicone surfactants are as effective as fluorinated surfactants with respect to performance of biosensors. These surfactants, when coated onto the mesh layer of the biosensor, are effective in facilitating the transport of aqueous test samples, such as blood, in the sample chamber.

Claims

1. A biosensor comprising a support, an arrangement of electrodes disposed on the support, a covering layer defining an enclosed space over the electrodes, and at least one mesh layer in the enclosed space between the covering layer and the electrodes, the at least one mesh layer coated with a mixture of silicone surfactants.

2. The biosensor of claim 1, wherein the covering layer comprises an aperture for receiving a biological sample.

3. The biosensor of claim 1, wherein the mixture of silicone surfactants comprises a surfactant having high molecular weight having satisfactory properties with respect to stability of the biosensor and a surfactant having low molecular weight having satisfactory properties for rapid filling of the enclosed space over the electrodes.

4. The biosensor of claim 3, wherein the silicone surfactant of high molecular weight and the silicone surfactant of low molecular weight have the formula:

5. The biosensor of claim 3, wherein the weight fraction of the silicone surfactant of high molecular weight in the mixture ranges from 1% to 99%, inclusive.

6. The biosensor of claim 3, wherein the weight fraction of the silicone surfactant of low molecular weight in the mixture ranges from 1% to 99%, inclusive.

7. The biosensor of claim 1, wherein the mixture of silicone surfactants comprises a number average molecular weight ranging from about 500 to about 30,000.

8. The biosensor of claim 1, wherein the mixture of silicone surfactants is coated from a solution in which the concentration of the mixture of silicone surfactants is at least 0.3%.

9. The biosensor of claim 1, wherein the mixture of silicone surfactants is present on the at least one layer of mesh at a weight of from 0.01% to 8 %, based on the weight of the at least one layer of mesh.

10. The biosensor of claim 1, comprising a single layer of mesh.

11. The biosensor of claim 1, comprising two layers of mesh.

12. The biosensor of claim 1, wherein the electrode arrangement comprises a working electrode that includes an enzyme capable of catalyzing a reaction involving a substrate for the enzyme and a mediator capable of transferring electrons between the enzyme-catalyzed reaction and the working electrode to create a current related to the activity of the enzyme and related to the concentration of the analyte in the sample.

13. The biosensor of claim 1, wherein the electrode arrangement comprises a working electrode that includes a substrate capable of catalyzing a reaction involving an enzyme for the substrate and a mediator capable of transferring electrons between the substrate-catalyzed reaction and the working electrode to create a current related to the activity of the substrate and related to the concentration of the analyte in the sample.

14. The biosensor of claim 1, wherein the electrode arrangement comprises a reference electrode or a counter electrode or both a reference and a counter electrode disposed on the support.

15. A biosensor comprising a support, an arrangement of electrodes disposed on the support, a covering layer defining a sample chamber over the electrodes, and at least one mesh layer in the sample chamber between the covering layer and the electrodes, the at least one mesh layer coated with a mixture of silicone surfactants, and wherein the volume of the sample chamber is from about 0.5 to about 2.5 microliters.

16. The biosensor of claim 15, wherein the mixture of silicone surfactants comprises a surfactant having high molecular weight having satisfactory properties with respect to stability of the biosensor and a surfactant having low molecular weight having satisfactory properties for rapid filling of the enclosed space over the electrodes.

17. The biosensor of claim 16, wherein the silicone surfactant of high molecular weight and the silicone surfactant of low molecular weight have the formula:

18. A biosensor comprising a support, an arrangement of electrodes disposed on the support, a covering layer defining a sample chamber over the electrodes, and at least one mesh layer in the sample chamber between the covering layer and the electrodes, the at least one mesh layer coated with a mixture of silicone surfactants, and wherein the sample chamber fills with the biological sample in less than 5 seconds.

19. The biosensor of claim 18, wherein the mixture of silicone surfactants comprises a surfactant having high molecular weight having satisfactory properties with respect to stability of the biosensor and a surfactant having low molecular weight having satisfactory properties for rapid filling of the enclosed space over the electrodes.

20. The biosensor of claim 19, wherein the silicone surfactant of high molecular weight and the silicone surfactant of low molecular weight have the formula:

21. The biosensor of claim 18, wherein the covering layer comprises an aperture for receiving a biological sample.

22. A method for monitoring the concentration of an analyte in a biological fluid, the method comprising:

applying a sample containing the analyte to a biosensor, the biosensor comprising;

a support, an arrangement of electrodes disposed on the support, a covering layer defining an enclosed space over the electrodes, and at least one mesh layer in the enclosed space between the covering layer and the electrodes, the at least one mesh layer coated with a mixture of silicone surfactants; and

determining the concentration of an analyte in the sample.

23. The method of claim 22, wherein the covering layer comprises an aperture for receiving a biological sample.

24. The method of claim 22, wherein the mixture of silicone surfactants comprises a surfactant having high molecular weight having satisfactory properties with respect to stability of the biosensor and a surfactant having low molecular weight having satisfactory properties for rapid filling of the enclosed space over the electrodes.

25. The method of claim 24, wherein the silicone surfactant of high molecular weight and the silicone surfactant of low molecular weight have the formula:

26. The method of claim 24, wherein the weight fraction of the silicone surfactant of high molecular weight in the mixture ranges from 1% to 99%, inclusive.

27. The method of claim 24, wherein the weight fraction of the silicone surfactant of low molecular weight in the mixture ranges from 1% to 99%, inclusive.

28. The method of claim 22, wherein the arrangement of electrode comprises a working electrode and a counter electrode.

29. The method of claim 28, wherein the working electrode comprises a working ink deposited on the working electrode, wherein the working ink comprises an analyte responsive enzyme and a redox mediator.