Heated electrochemical cell

• US 20030079987A1
• Filed: 09/16/2002
• Published: 05/01/2003
• Est. Priority Date: 03/12/1998
• Status: Abandoned Application

• Current Assignee: Lifescan Incorporated (Duv Holding Corporation)
• Original Assignee: Lifescan Incorporated (Duv Holding Corporation)
• Inventors: Hodges, Alastair, Beck, Thomas W.
• Application Number:
  US10/246,371
• Publication Number:
  US 20030079987A1
• Time in Patent Office: Days
• US Class Current: 204/409
• CPC Class Codes: G01N 27/3272 Test elements therefor, i.e. disposable laminated substrates with electrodes, reagent and channels optical biosensors G01N33/52

Abstract

The invention provides a method for determining the concentration of an analyte in a sample comprising the steps of heating the sample and measuring the concentration of the analyte or the concentration of a species representative thereof in the sample at a predetermined point on a reaction profile by means that are substantially independent of temperature. Also provided is an electrochemical cell comprising a spacer pierced by an aperture which defines a cell wall, a first metal electrode on one side of the spacer extending over one side of the aperture, a second metal electrode on the other side of the spacer extending over the side of the aperture opposite the first electrode, means for admitting a sample to the cell volume defined between the electrodes and the cell wall, and means for heating a sample contained within the cell.

Claims

1. A method of heating an electrochemical cell, the electrochemical cell comprising a spacer pierced by an aperture which defines a cell wall, a first metal electrode on one side of the spacer extending over one side of the aperture, a second metal electrode on the other side of the spacer extending over the side of the aperture opposite the first electrode, an ingress for admitting a sample to a cell volume defined between the electrodes and the cell wall, and a resistive element for heating a sample contained within the cell, the method comprising:

applying a potential across the resistive element to generate an amount of heat;

interrupting a potential across the resistive element; and

applying a potential between the first electrode and the second electrode to perform an electrochemical assay of an analyte.

2. The method according to claim 1, wherein a potential across the resistive element is maintained during the assay of the analyte at an initial level or at a lower level sufficient to substantially maintain a sample temperature.

3. The method according to claim 1, wherein a current flowing through the resistive element is monitored and the potential automatically adjusted so as to maintain a power output.

4. The method according to claim 3, wherein the power output is adjusted on a basis of an ambient temperature measured by a separate sensor.

5. The method according to claim 1, wherein the electrochemical cell further comprises means of measuring a concentration of the analyte or a concentration of a species representative of the analyte in a sample at a predetermined point on a reaction profile by means that are substantially independent of a temperature of the sample in the electrochemical cell.

6. The method according to claim 1, wherein the electrochemical cell further comprises a mediator, wherein the mediator comprises a species representative of a concentration of the analyte.

7. The method according to claim 6, wherein the mediator is an enzyme mediator.

8. The method according to claim 1, wherein the step of applying a potential across the resistive element to generate an amount of heat raises an analyte temperature by from 5 to 15°

C.

9. The method according to claim 1, wherein the step of applying a potential across the resistive element to generate an amount of heat raises an analyte temperature to a final temperature within a period of 2 to 10 seconds.

10. The method according to claim 1, wherein the step of applying a potential across the resistive element to generate an amount of heat raises an analyte temperature to a peak temperature within 2 to 5 seconds.

11. The method according to claim 1, wherein the electrochemical cell comprises a glucose sensor.

12. The method according to claim 1, wherein the electrochemical cell comprises a glucose sensor capable of measuring a concentration of glucose in a blood sample.

13. The method according to claim 1, wherein the electrochemical cell comprises an enzyme.

14. The method according to claim 13, wherein the enzyme comprises glucose dehydrogenase.

15. The method according to claim 14, wherein the electrochemical cell further comprises an oxidizing mediator.

16. The method according to claim 15, wherein the oxidizing mediator comprises ferricyanide.

17. The method according to claim 1, wherein the electrochemical cell comprises means for applying a potential to the resistive element that is capable of measuring a current flowing through the resistive element and automatically adjusting the potential so as to maintain a power output.

18. The method according to claim 17, wherein the power output is capable of being adjusted on a basis of an ambient temperature measured by a separate sensor.

19. The method according to claim 1, wherein the analyte comprises glucose.