Analyte determination methods and devices

• US 8,080,153 B2
• Filed: 05/29/2008
• Issued: 12/20/2011
• Est. Priority Date: 05/31/2007
• Status: Expired due to Fees

• Current Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories Incorporated)
• Inventors: Feldman, Benjamin J., Wang, Yi, Chen, Ting, Tran, Lam
• Primary Examiner(s): Barton, Jeffrey T
• Assistant Examiner(s): ROSENWALD, STEVEN ERIC
• Application Number:
  US12/129,423
• Publication Number:
  US 20090000959A1
• Time in Patent Office: 1,300 Days
• Field of Search: 205/775, 205/777.5, 205/792, 204/403.01, 204/403.14, 204/403.04, 204/403.09, 204/403.11, 204/403.12
• US Class Current: 205/777.5
• CPC Class Codes: C12Q 1/006 for glucose
• CPC Class Codes: C12Q 1/54 involving glucose or galactose

Abstract

The present invention provides methods and apparatuses for analyte detection.

Claims

1. A method of determining a hematocrit-corrected value of an analyte in a sample, the method comprising:

contacting a test strip with a sample comprising an analyte;

determining an uncorrected value of the analyte R_r;

determining a fill time of the sample on the test strip; and

calculating a hematocrit-corrected value R_c of the analyte using the equation R_c=R_r+((fill time−

0.4 S)*R_r).

2. The method of claim 1, wherein said sample is a blood sample.

3. The method of claim 2, wherein said analyte is glucose.

4. The method of claim 1, wherein the fill time of the sample on the test strip is determined using a coulometric method.

5. The method of claim 1, wherein the fill time of the sample on the test strip is determined using an amperometric method.

6. The method of claim 1, wherein the test strip is configured to provide a result using about 1 microliter or less of sample.

7. The method of claim 1, wherein the test strip comprises a working electrode, and a counter-reference electrode, and wherein the working electrode or the counter-reference electrode comprises at least two sub-electrodes whose fill time can be measured independently.

8. The method of claim 7, wherein the fill time of the test strip is calculated by measuring the time for the sample to travel between the first sub-electrode and the second sub-electrode.

9. The method of claim 7, wherein the working electrode or the counter-reference electrode is divided into three independent sub-electrodes:

a first sub-electrode, a second sub-electrode, and a third sub-electrode.

10. The method of claim 9, wherein three different fill times are determined on the test strip, wherein a first fill time is determined between the first sub-electrode and the second sub-electrode, a second fill time is determined between the second sub-electrode and the third sub-electrode, and wherein a third fill time is determined between the first sub-electrode and the third sub-electrode.

11. A method for correcting the effect of hematocrit on a blood glucose measurement, the method comprising:

filling an electrochemical test strip with a blood sample, wherein the test strip is configured to determine a fill time using electrochemical current measurements;

measuring the fill time of the blood sample on the test strip;

determining an initial glucose concentration R_r of the blood sample; and

calculating a corrected glucose concentration R_c of the blood sample using the equation R_c=R_r+((fill time−

0.4 S)*R_f).

12. A system to determine a hematocrit-corrected value of an analyte, the system comprising:

a test strip for contacting a sample;

a meter configured to receive the test strip, wherein the meter is programmed to determine a fill time of the test strip, determine an uncorrected value of the analyte R_r, and determine a hematocrit-corrected value of the analyte R_c, using the equation R_c=R_r+((fill time−

0.4 S)*R_f).

13. The system of claim 12, wherein the analyte is glucose.

14. The system of claim 13, wherein the sample is a blood sample.

15. The system of claim 14, wherein the system is configured to provide a hematocrit-corrected value of the analyte using about 1 microliter or less of the sample.

16. The system of claim 12, wherein the meter uses a coulometric method to calculate the hematocrit-corrected value of the analyte.

17. The system of claim 12, wherein the meter uses an amperometric method to calculate the hematocrit-corrected value of the analyte.

18. The system of claim 17, wherein the test strip comprises a working electrode and a counter-reference electrode, and wherein the working electrode or the counter-reference electrode comprises two independent sub-electrodes.

19. The system of claim 18, wherein the two independent sub-electrodes are configured to measure the time required for a sample to move across the test strip from the first sub-electrode to the second sub-electrode, thereby determining a fill time.