ANALYTE TEST STRIP WITH IMPROVED REAGENT DEPOSITION

• US 20090057146A1
• Filed: 09/04/2007
• Published: 03/05/2009
• Est. Priority Date: 09/04/2007
• Status: Active Grant

• Current Assignee: Cilag Gmbh International (Johnson & Johnson)
• Original Assignee: Lifescan Incorporated (Duv Holding Corporation)
• Inventors: Dato, Remedios, Teodorczyk, Maria, Leong, Koon-wah
• Granted Patent: US 7,943,022 B2
• Time in Patent Office: Days
• US Class Current: 204/403.10
• CPC Class Codes: C12Q 1/001 Enzyme electrodes
• CPC Class Codes: G01N 27/3272 Test elements therefor, i.e. disposable laminated substrates with electrodes, reagent and channels optical biosensors G01N33/52
• CPC Class Codes: G01N 33/521 Single-layer analytical elements

Abstract

An analyte, system, strip and method are described. In one example, an analyte test strip is provided that includes a substrate, electrically conductive material and an isolated portion of the electrically conductive material. The substrate has a generally planar surface that extends from a first end to a second end. The electrically conductive material is disposed on the generally planar surface to define a plurality of electrodes spaced apart from each other. The isolated portion of the electrically conductive material is disposed between at least two electrodes so that the isolated portion is not in electrical communication with the plurality of electrodes.

Claims

1. An analyte test strip comprising:

a substrate having a generally planar surface that extends from a first end to a second end;

an electrically conductive material disposed on the generally planar surface to define a plurality of electrodes spaced apart from each other; and

an isolated portion of the electrically conductive material disposed between at least two electrodes so that the isolated portion is not in electrical communication with the plurality of electrodes.

2. The test strip of claim 1, in which the width of the isolated portion is from about 120 microns to about 200 microns.

3. The test strip of claim 1, in which the distance between one electrode and the isolated portion and the distance between the isolated portion and another electrode is from about 2 microns to about 50 microns.

4. The test strip of claim 1, in which less than 10% of the conductive material is removed to form the plurality of electrodes.

5. The test strip of claim 1, further including another isolated portion of electrically conductive material distal to both the first end and one of the electrodes so that capillary action is assisted during filling of the test strip with a fluid sample deposited on the test strip.

6. The test strip of claim 1, in which the electrodes and the isolated portion of electrically conductive material is coated with a hydrophilic material.

7. An analyte measurement system for measuring a concentration of an analyte in a fluid sample, the system comprising:

a meter comprising;

an electronic circuit for applying a test voltage between the reference electrode and the working electrode;

a signal processor; and

a test strip comprising a substrate having a reference electrode and a working electrode that are separated by an isolated portion of electrically conductive material so that capillary action is assisted during filling of the test strip with the fluid sample.

8. The system of claim 7, in which the width of the isolated portion is from about 120 microns to about 200 microns, and in which the distance between the reference electrode and the isolated portion and the distance between the isolated portion and the working electrode is from about 2 microns to about 50 microns.

9. The system of claim 7, in which less than 10% of the conductive material is removed to form the reference and working electrode.

10. A test strip for measuring a concentration of an analyte in a fluid sample, the test strip comprising:

a substrate material;

a reference electrode disposed on the substrate;

a first working electrode disposed on the substrate proximate the reference electrode;

a second working electrode disposed on the substrate proximate the first working electrode; and

an isolated portion of electrically conductive material is located proximal to one of the first and second working electrodes and distal to the reference electrode.

11. The test strip of claim 10, further comprising a first isolated portion between the reference electrode and the first working electrode and a second isolated portion between the first working electrode and the second working electrode, and in which the reference electrode, the first working electrode, the second working electrode and the isolated portion of electrically conductive material are coated with a hydrophilic material.

12. The test strip of claim 11, in which the hydrophilic material comprises 2-mercaptoethanesulfonic acid sodium salt.

13. The test strip of claim 10, in which the isolated portion comprises a substantially triangular shape portion.

14. The test strip of claim 10, further comprising a vent opening through the isolated portion of electrically conductive material and through the substrate.

15. The test strip of claim 10, in which less than 10% of the conductive material is removed to form the reference and working electrode.

16. The test strip of claim 10, in which the width of the isolated portion from about 120 microns to about 200 microns.

17. The test strip of claim 10, in which the distance between the reference electrode and the first isolated portion and the distance between the first isolated portion and the working electrode is from about 2 microns to about 50 microns.

18. A method of making an analyte test strip, the method comprising:

depositing a layer of a conductive material on a substrate; and

removing selective portions of the layer of conductive material to define a plurality of electrodes with at least an electrically isolated island of conductive material separated from any of the electrodes at a distance of about 50 microns or less to electrically isolate the island from the electrodes.

19. The method of claim 18, in which the removing comprises broad field laser ablating the layer of conductive material over a duration of less than 100 nanoseconds.

20. The method of claim 18, further comprising coating the electrodes and the at least one electrically isolated island with a layer of material to render such surfaces hydrophilic.

21. The method of claim 18, further comprising depositing a reagent layer over at least two electrodes and the at least one island.

22. The method of claim 21, further comprising attaching a cover layer to the conductive layer.

23. The method of claim 22, further comprising forming a chamber defined by a surface of the reagent layer, a wall of the cover layer and a top cover over the chamber.

24. The method of claim 23, in which the removing comprises ablating the conductive layer to form first and second electrode with a first island interposed therebetween, a second island between a third electrode and the second electrode, and a third island proximate the third electrode.

25. The method of claim 24, further comprising puncturing an orifice through the substrate and the conductive layer.