Electrodes Having at Least One Sensing Structure and Methods for Making and Using the Same

Patent metadata

Field	Value
Publication number	US-2017363564-A1
Application number	US-201515520784-A
Country	US
Kind code	A1
Filing date	Oct 22, 2015
Priority date	Oct 23, 2014
Publication date	Dec 21, 2017
Grant date	—

Abstract

Embodiments of the present disclosure relate to electrochemical analyte sensor electrodes that have one or more sensing structures, each structure has a respective perimeter at least partially around it to define the structure so that each of the structures have a liquid limiting barrier around their perimeters. The liquid limiting perimeter may completely or partially encompass the perimeter of each sensing structure of the electrode. Also provided are methods for fabricating the electrodes, analyte sensors employing the subject electrodes, and methods of using the analyte sensors in analyte monitoring.

First claim

That which is claimed is:

1 . An electrode comprising:
a non-conductive material; a conductive layer disposed on the material; and a sensing structure on the conductive layer comprising a removed portion of conductive material forming a fluid barrier perimeter; and reagent comprising analyte responsive enzyme positioned within the sensing structure.

2 . The electrode according to claim 1 , wherein the fluid barrier perimeter surrounds the sensing structure.

3 . The electrode according to claim 1 , wherein the fluid barrier perimeter is an incomplete circle around the sensing structure.

4 . The electrode according to claim 3 , wherein the circle is incomplete by 50 μm or less.

5 . The electrode according to claim 1 , wherein the fluid barrier perimeter is a single portion of removed conductive material.

6 . The electrode according to claim 1 , wherein the fluid barrier perimeter is a plurality of portions of removed conductive material.

7 . The electrode according to any one of the previous claims, wherein the fluid barrier perimeter has a depth from 1 μm to 25 μm into the material.

8 . The electrode according to claim 7 , wherein the fluid barrier perimeter has a depth of 10 μm.

9 . The electrode according to any one of the previous claims, wherein the conductive layer comprises a material selected from the group consisting of silver, indium tin oxide, gold, platinum, copper, nickel, rhodium, ruthenium, ruthenium dioxide, cobalt, zinc, titanium, palladium, carbon, platinum-carbon and conductive polymer.

10 . The electrode according to claim 9 , wherein the conductive layer comprises gold.

11 . The electrode according to any one of the previous claims, wherein the conductive layer has a thickness of from 50 μm to 200 μm.

12 . The electrode according to claim 11 , wherein the conductive layer has a thickness of 180 μm.

13 . The electrode according to claim 1 , wherein the removed portion of conductive material spans an entire thickness of the conductive material.

14 . The electrode according to claim 1 , wherein the removed portion of conductive material is less than an entire thickness of the conductive material.

15 . The electrode according to claim 14 , wherein the array comprises two or more individual sensing structures.

16 . The electrode according to claim 14 or claim 15 , wherein the array comprises 100 or more individual sensing structures.

17 . The electrode according to any of claims 14 - 16 , wherein the electrode comprises sensing structures at a density of from 2 to 1000 sensing structures per mm 2 .

18 . The electrode according to any one of claims 14 - 17 , wherein the array comprises inter-sensing structure areas between sensing structures.

19 . The electrode according to claim 18 , wherein the inter-sensing structure areas surround the sensing structures.

20 . The electrode according to claim 18 or claim 19 , wherein the inter-sensing structure areas are free of reagent.

21 . The electrode according to any one of claims 18 - 20 , wherein the distance between sensing structures is from 1 μm to 500 μm.

22 . The electrode according to any one of the previous claims, wherein the sensing structures have an average diameter of 200 μm or less.

23 . The electrode according to any one of the previous claims, further comprising a membrane disposed over conductive layer.

24 . The electrode according to any one of the previous claims, wherein the analyte-responsive enzyme comprises a glucose-responsive enzyme.

25 . The electrode according to any one of the previous claims, wherein the reagent further comprises a redox mediator.

26 . The electrode according to claim 25 , wherein the redox mediator comprises a ruthenium-containing complex or an osmium-containing complex.

27 . A method for monitoring a level of an analyte in a subject, the method comprising:
positioning at least a portion of an analyte sensor into a skin of a subject, wherein the analyte sensor comprises:
a working electrode; and
a counter electrode,
wherein the working electrode comprises:
a non-conductive material;
a conductive layer disposed on the material; and
a sensing structures on the conductive layer comprising a removed portion of conductive material forming a fluid barrier perimeter; and

reagent comprising analyte responsive enzyme positioned within the sensing structure; and
determining a level of an analyte over a period of time from signals generated by the analyte sensor,
wherein the determining over a period of time provides for monitoring the level of the analyte in the subject.

28 . The method according to claim 27 , wherein the fluid barrier perimeter surrounds the sensing structure.

29 . The method according to claim 27 , wherein the fluid barrier perimeter is an incomplete circle around the sensing structure.

30 . The method according to claim 29 , wherein the circle is incomplete by 50 μm or less.

31 . The method according to claim 27 , wherein the fluid barrier perimeter is a single portion of removed conductive material.

32 . The method according to claim 27 , wherein the fluid barrier perimeter is a plurality of portions of removed conductive material.

33 . The method according to any one of claims 27 - 32 , wherein the fluid barrier perimeter has a depth from 1 μm to 25 μm into the material.

34 . The method according to claim 33 , wherein the fluid barrier perimeter has a depth of 10 μm.

35 . The method according to any one of claims 27 - 34 , wherein the conductive layer comprises a material selected from the group consisting of silver, indium tin oxide, gold, platinum, copper, nickel, rhodium, ruthenium, ruthenium dioxide, cobalt, zinc, titanium, palladium, carbon, platinum-carbon and conductive polymer.

36 . The method according to claim 35 , wherein the conductive layer comprises gold.

37 . The method according to any one of claims 27 - 36 , wherein the conductive layer has a thickness of from 50 μm to 200 μm.

38 . The method according to claim 37 , wherein the conductive layer has a thickness of 180 μm.

39 . The method according to claim 27 , wherein the removed portion of conductive material spans an entire thickness of the conductive material.

40 . The method according to claim 27 , wherein the removed portion of conductive material is less than an entire thickness of the conductive material.

41 . The method according to claim 40 , wherein the array comprises two or more individual sensing structures.

42 . The method according to claim 40 or claim 41 , wherein the array comprises 100 or more individual sensing structures.

43 . The method according to any one of claims 40 - 42 , wherein the electrode comprises sensing structures at a density of from 2 to 1000 sensing structures per mm 2 .

44 . The method according to any one of claims 40 - 43 , wherein the array comprises inter-sensing structures areas between sensing structures.

45 . The method according to claim 44 , wherein the inter-sensing structures areas

Assignees

• Abbott Diabetes Care Inc

Inventors

• Hoss Udo
• Khan Tahir Sadik
• Le Phu X

Classifications

• G01N27/413

  Concentration cells using liquid electrolytes {measuring currents or voltages in voltaic cells} · CPC title

• A61B5/1486

  using enzyme electrodes, e.g. with immobilised oxidase · CPC title

• G01N27/3271 Primary

  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) · CPC title

• H01M4/02 Primary

  Electrodes composed of, or comprising, active material · CPC title