Test Sensor Reagent Having Cellulose Polymers

• US 20090152128A1
• Filed: 11/13/2006
• Published: 06/18/2009
• Est. Priority Date: 11/14/2005
• Status: Active Grant

• Current Assignee: Ascensia Diabetes Care Holdings AG (PHC Holdings Corporation)
• Original Assignee: Bayer Healthcare LLC (Bayer AG)
• Inventors: Chu, Amy H., Spradlin, Hope G., Edelbrock, Andrew J.
• Granted Patent: US 8,940,153 B2
• Time in Patent Office: Days
• US Class Current: 205/777.500
• CPC Class Codes: C12Q 1/006 for glucose
• CPC Class Codes: C12Q 1/26 involving oxidoreductase

Abstract

A test sensor reagent for measuring the concentration of analytes in body fluids includes cellulose polymers for improving the stability of the test sensor and reducing the total assay time. The test sensor reagent also includes an enzyme, an electron transfer mediator and a rheological additive.

Claims

1. A test sensor reagent composition adapted to assist in determining an analyte concentration of a fluid sample, the reagent comprising an enzyme, an electron transfer mediator, a cellulose polymer and a rheological additive.

2. The composition according to claim 1, wherein the reagent comprises from about 3.6 wt. % to about 6.0 wt. % of the cellulose polymer.

3. The composition according to claim 1, wherein the reagent comprises from about 1 wt. % to about 4 wt. % of the enzyme.

4. The composition according to claim 1, wherein the reagent comprises from about 15 wt. % to about 20 wt. % of the electron transfer mediator.

5. The composition according to claim 1, wherein the reagent comprises from about 0.2 wt. % to about 1.6 wt. % of the rheological additive.

6. The composition according to claim 1, wherein the reagent comprises from about 3.6 wt. % to about 6.0 wt. % of a hydroxyethyl cellulose polymer, from about 1 wt. % to about 4 wt. % of a glucose oxidase enzyme, from about 15 wt. % to about 20 wt. % of a ferricyanide mediator and from about 0.2 wt. % to about 1.6 wt. % of a smectite clay.

8. The composition according to claim 1, wherein the reagent further comprises about 10 mMolar to about 500 mMolar of a citrate buffer.

7. (canceled)

9-12. -12. (canceled)

13. A method of determining an analyte concentration of a fluid sample comprising the acts of:

providing an electrochemical test sensor adapted to assist in determining the analyte concentration, the electrochemical test sensor comprising a plurality of electrodes including a first electrode and a second electrode, a fluid receiving area and a test sensor reagent, the test sensor reagent including a cellulose polymer; and

determining the analyte concentration in an assay time of less than about 35 seconds.

14. The method according to claim 13, wherein the cellulose polymer comprises hydroxyethyl cellulose.

15. The method according to claim 13, wherein the test sensor reagent further comprises an enzyme, an electron transfer mediator and a rheological additive.

16. The method according to claim 15, wherein the electron transfer mediator comprises a ferricyanide mediator.

17. The method according to claim 15, wherein the rheological additive comprises a smectite clay.

19. The method according to claim 15, wherein the enzyme comprises a glucose oxidase enzyme.

20. The method according to claim 13, wherein the total assay time is reduced to less than about 25 seconds.

18. (canceled)

21. A method of determining an analyte concentration of a fluid sample, the method comprising the acts of:

providing a fluid sample;

contacting a test sensor with the fluid sample, the fluid sample having at least one analyte;

contacting the fluid sample with a reagent comprising a cellulose polymer, the cellulose polymer assisting in stabilizing the test sensor;

providing an electrical signal indicative of the analyte in the fluid sample; and

determining the analyte using the electrical signal.

22. The method according to claim 21, wherein the analyte concentration is determined in less than about 35 seconds.

23. The method according to claim 21, wherein the reagent comprises hydroxyethyl cellulose.

24. The method according to claim 23, wherein the reagent further comprises a glucose oxidase enzyme, a ferricyanide mediator and a smectite clay.

25. A method of determining an analyte concentration of a fluid sample, the method comprising the acts of:

providing the fluid sample;

contacting a test sensor with the fluid sample, the fluid sample having at least one analyte;

contacting the fluid sample with a reagent comprising a cellulose polymer, the cellulose polymer assisting in stabilizing the test sensor; and

determining the analyte concentration of the fluid sample.

26. The method according to claim 25, wherein the test sensor is an optical test sensor.

27. A method of screen printing on a substrate, the method comprising the acts of:

providing a screen that includes a first portion with a photosensitive emulsion and a second portion formed in the absence of a photosensitive emulsion;

supplying a reagent on the screen, the reagent comprising a solvent, a cellulose polymer and an enzyme to assist in determining an analyte concentration of a fluid sample; and

contacting the reagent onto the substrate via the second portion of the screen.

28. The method according to claim 27, wherein the reagent further comprises a rheological additive.

29. The method according to claim 28, wherein the Theological additive is a smectite clay.

31. The method according to claim 28, wherein the rheological additive is a thixotropic material.

32. The method according to claim 27, wherein the reagent further comprises an electron transfer mediator.

30. (canceled)