Method for Improving Measurement Accuracy and Devices and Systems Related Thereto

• US 20140178909A1
• Filed: 12/19/2013
• Published: 06/26/2014
• Est. Priority Date: 12/21/2012
• Status: Active Grant

• Current Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories)
• Original Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories)
• Inventors: Tonks, Simon X.
• Granted Patent: US 9,273,337 B2
• Time in Patent Office: Days
• US Class Current: 435/14
• CPC Class Codes: C12Q 1/006 for glucose
• CPC Class Codes: C12Q 1/26 involving oxidoreductase
• CPC Class Codes: C12Q 1/32 involving dehydrogenase
• CPC Class Codes: G01N 27/12 of a solid body in dependence upon absorption of a fluid; of a solid body in dependence upon reaction with a fluid , for detecting components in the fluid
• CPC Class Codes: G01N 27/226 Construction of measuring vessels; Electrodes therefor
• 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 present disclosure relates to methods and devices for providing accurate measurement of a property of a sample. The method comprises obtaining a plurality of independent measurements of the property. The plurality of values of the property of the sample obtained by the plurality of independent measurements is compared to determine whether one or more of the values is an outlier.

Claims

1. A method for measuring a property of a sample, the method comprising:

obtaining a first measurement of the property;

obtaining a second measurement of the property;

obtaining a third measurement of the property;

deriving a first value, a second value and a third value of the property using the first, second, and third measurements, respectively, wherein the first, second, and third measurements are obtained by different methods;

comparing the first, second, and third values to determine whether one of the values is an outlier.

2. The method of claim 1, wherein when two of the first, second, and third values are in agreement, the method comprises providing a single value of the property based on two of the first, second, and third values that are in agreement.

3. The method of claim 1, wherein when the first, second, and third values are in agreement, the method comprises obtaining a single value from the first, second, and third values.

4. The method of claim 1, wherein the property of the sample is selected from the group consisting of concentration of an analyte, hematocrit, temperature, and viscosity.

5. The method of claim 1, wherein the method comprises contacting the sample with a sensor prior to the obtaining the first, second, and third measurements, the sensor comprising a first electrode, a second electrode, and a third electrode, wherein the sample contacts the first and the second electrode prior to contacting the third electrode.

6. The method of claim 5, wherein the property is hematocrit and obtaining the first measurement comprises determining fill-time of the sample by measuring time elapsed between detecting a signal between the first electrode and the second electrode and another signal between the first electrode and the third electrode;

obtaining the second measurement comprises measuring a first signal at the second electrode after the sample chamber is substantially filled with the sample; and

obtaining the third measurement comprises measuring a second signal at the third electrode, and wherein the method comprises deriving a first value, a second value and a third value of the hematocrit using the first, second, and third measurements, respectively, and comparing the first, second, and third values to determine whether one of the hematocrit values is an outlier.

7. The method of claim 6, wherein the sensor comprises an enzyme responsive to an analyte and a redox mediator, the method further comprising measuring an analyte related signal at the second electrode after measuring the first signal and determining concentration of the analyte using the analyte related signal.

8. The method of claim 7, wherein determining concentration of the analyte comprises correcting the concentration of the analyte using a value of the property.

9. The method of claim 6, wherein the first and second signals are selected from the group consisting of voltage, current, resistance, capacitance, charge, conductivity, or combination thereof.

10. The method of claim 5, wherein the analyte is glucose.

11. The method of claim 5, wherein the enzyme comprises glucose dehydrogenase or glucose oxidase.

12. The method of claims 11, wherein the glucose dehydrogenase is nicotinamide dinucleotide glucose dehydrogenase (NAD-GDH), or pyrrole quinoline quinone glucose dehydrogenase (PQQ-GDH), or flavin-adenine dinucleotide glucose dehydrogenase (FAD-GDH).

13. The method of claim 5, wherein the analyte is β

-hyroxybutyrate.

14. The method of claim 5, wherein the enzyme is hydroxybutyrate dehydrogenase.

15. The method of claim 4, wherein the first, second, and third electrodes are coplanar.

16. The method of claim 4, wherein one of the first, second, and third electrodes is in facing configuration with the other two electrodes.

17. The method of claim 4, wherein the electrodes are arranged such that the sample contacts the first electrode before contacting the third electrode.

18. The method of claim 4, wherein the electrodes are arranged such that the sample contacts the second electrode before contacting the third electrode.

19. A method for using an analyte sensor, the method comprising:

contacting a sample comprising an analyte with an analyte sensor comprising a sample chamber comprising a first electrode, a second electrode, and a third electrode;

an enzyme responsive to the analyte and a redox mediator;

determining fill-time by measuring time elapsed between detecting a signal between the first electrode and the second electrode and another signal between the first electrode and the third electrode, wherein the fill-time is related to hematocrit of the sample;

measuring a first signal at the second electrode after the sample chamber is substantially filled with the sample, wherein the first signal is substantially independent of the analyte concentration and is related to hematocrit of the sample;

measuring an analyte related signal at the second electrode after measuring the first signal;

measuring a second signal at the third electrode after measuring the analyte related signal, wherein the second signal is related to hematocrit of the sample;

determining concentration of the analyte.

20. The method of claim 19, wherein the method comprises deriving first, second, and third hematocrit values of the sample using the fill-time, the first signal, and the second signal.

21. The method of claim 20, wherein the method further comprises comparing the first, second, and third hematocrit values of the sample.

22. The method of claim 21, wherein the method comprises calculating a single hematocrit value based on the first, second and third hematocrit values when the first, second, and third hematocrit values of the sample are in agreement.

23. The method of claim 21, wherein the method comprises calculating a single hematocrit value based on two of the first, second, and third hematocrit values when only the two of the first, second, and third hematocrit values are in agreement.

24. The method of claim 22, wherein the method further comprises correcting the concentration of the analyte according to the single hematocrit value.

25. The method of claim 19, wherein the first and second signals are selected from the group consisting of voltage, current, resistance, impedance, capacitance, or combination thereof.

26. The method of claim 19, wherein the analyte is glucose.

27. The method of claim 19, wherein the enzyme comprises glucose dehydrogenase or glucose oxidase.

28. The method of claim 27, wherein the glucose dehydrogenase is nicotinamide dinucleotide glucose dehydrogenase (NAD-GDH), pyrrole quinoline quinone glucose dehydrogenase (PQQ-GDH), or flavin-adenine dinucleotide glucose dehydrogenase (FAD-GDH).

29. The method of claim 19, wherein the analyte is β

-hyroxybutyrate.

30. The method of claim 19, wherein the enzyme is hydroxybutyrate dehydrogenase.

31. The method of claim 19, wherein the first, second, and third electrodes are coplanar.

32. The method of claim 19, wherein one of the first, second, and third electrodes is in facing configuration with the other two electrodes.

33. The method of claim 19, wherein the electrodes are arranged such that the sample contacts the first electrode before contacting the third electrode.

34. The method of claim 19, wherein the electrodes are arranged such that the sample contacts the second electrode before contacting the third electrode.

35. A meter comprising a memory, a processor, and a display,

the memory operably coupled to the processor, wherein the memory comprises instructions stored therein to be executed by the processor, the instructions comprising:

instructions for obtaining a first measurement of a property of a sample applied to an analyte sensor inserted into the meter;

instructions for obtaining a second measurement of the property;

instructions for obtaining a third measurement of the property;

instructions for deriving a first value, a second value and a third value of the property using the first, second, and third measurements, respectively, wherein the first, second, and third measurements are performed using different methods;

instructions for comparing the first, second, and third values to determine whether one of the values is an outlier.

36. The meter of claim 35, wherein when two of the first, second, and third values are in agreement, the instructions comprises instructions for providing a single value of the property based on two of the first, second, and third values that are in agreement.