SYSTEM AND METHOD OF PROCESSING A CURRENT SAMPLE FOR CALCULATING A GLUCOSE CONCENTRATION

• US 20090322341A1
• Filed: 06/30/2008
• Published: 12/31/2009
• Est. Priority Date: 10/17/2005
• Status: Active Grant

• Current Assignee: Cilag Gmbh International (Johnson & Johnson)
• Original Assignee: Lifescan Incorporated (Duv Holding Corporation)
• Inventors: Ebner, Manfred, Christol, James, Kraft, Ulrich
• Granted Patent: US 8,093,903 B2
• Time in Patent Office: Days
• US Class Current: 324/444
• CPC Class Codes: G01N 27/3274 Corrective measures, e.g. error detection, compensation for temperature or hematocrit, calibration coding of calibration information G01N33/48771

Abstract

A system and method of processing a test current for an analyte measurement in a fluid using a test strip and a test meter are disclosed. The method comprises sampling the test current at a pre-determined sampling rate to acquire a plurality of A/D conversions. The method also comprises filtering out at least a highest magnitude A/D conversion and a lowest magnitude A/D conversion leaving a plurality of accepted A/D conversions. Further, the method comprises calculating an average or a summation of the plurality of accepted A/D conversions and converting the average or the summation into a glucose concentration.

Claims

1-12. -12. (canceled)

13. A method of determining analyte concentration in a physiological fluid, comprising:

receiving, by a test meter, a sample of physiological fluid causing a current to run through the fluid sample;

sampling the magnitude of the current a plurality of times to form a plurality of analog to digital (A/D) conversions;

discarding a subset of the plurality of A/D conversion, based on the magnitudes; and

generating an analyte concentration based on the remaining A/D conversions.

14. The method of claim 13, further comprising:

determining the presence of the fluid in a position to be detectable by the meter.

15. The method of claim 13, further comprising:

identifying the presence of the fluid in apposition to be detectable by the meter; and

determining whether the identification is in error.

17. The method of claim 13, further comprising:

determining whether the initial current reading is greater than a predetermined threshold value in a fluid detection mode;

measuring the current during a check time interval; and

returning back to the fluid detection mode if the current drops below the threshold value during the check time interval.

21. The method of claim 13, wherein the step of discarding a subset of the plurality of A/D conversions comprises filtering Out at least a highest magnitude A/D conversion and a lowest magnitude A/D conversion leaving a plurality of accepted A/D conversions.

22. The method of claim 13, wherein the step of generating an analyte concentration based on the remaining A/D conversions comprises:

calculating an average or a summation of said plurality of accepted A/D) conversions; and

converting said average or said summation into an analyte concentration.

23. The method of claim 13, wherein the step of generating an analyte concentration based on the remaining A/D conversions comprises:

repeating the steps of sampling, discarding and generating more than once to calculate a total more than one current samples; and

summing together said more than one current samples to form a current reading.

24. The method of claim 23, further comprising:

repeating the steps of repeating and summing at least one more times to calculate a total at least two current readings;

summing together said at least two current readings to form a final Current value; and

calculating a glucose concentration based on said final current value.

25. The method of claim 13, wherein the analyte comprises glucose.

26. The method of claim 13, wherein the analyte comprises cholesterol.

27. The method of claim 13, wherein the sampling comprises sampling 16 analog-to-digital conversions during a current time sampling interval.

28. The method of claim 27, wherein the discarding comprises filtering out four highest analog-to-digital conversions and four lowest analog-to-digital conversions so as to provide eight analog-to-digital conversions for determination of analyte concentration.

29. The method of claim 28, further comprising summing the eight analog-to-digital conversions together.

30. The method of claim 28, further comprising averaging the eight analog-to-digital conversions.

16. (canceled)

18-20. -20. (canceled)

31. A method to determine analyte concentration in a fluid sample in contact with two electrodes, the method comprising:

applying a voltage to the electrodes;

sampling the magnitude of current generated in the fluid sample to provide a plurality of analog-to-digital conversions;

discarding a subset of the plurality of analog-to-digital conversions; and

generating an analyte concentration based on remaining analog-to-digital conversions.

32. The method of claim 31, further comprising:

determining a maximum current peak time;

determining a change in current after the maximum current peak time during a time interval; and

selectively indicating an error based on the change in current.