Method and System for Providing Calibration of an Analyte Sensor in an Analyte Monitoring System

• US 20130231541A1
• Filed: 02/13/2013
• Published: 09/05/2013
• Est. Priority Date: 08/09/2006
• Status: Active Grant

• Current Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories Incorporated)
• Inventors: Hayter, Gary Alan, Doniger, Kenneth J., Budiman, Erwin Satrya, Zhang, Songbiao, Mazza, John Charles
• Granted Patent: US 9,408,566 B2
• Time in Patent Office: Days
• US Class Current: 600/345
• CPC Class Codes: A61B 2560/0223 of calibration, e.g. protocols for calibrating sensors
• CPC Class Codes: A61B 5/0004 characterised by the type of physiological signal transmitted
• CPC Class Codes: A61B 5/14503 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors A61B5/1459, A61B5/1464, A61B5/1473, A61B5/1482, A61B5/14865 take precedence
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/1468 using chemical or electrochemical methods, e.g. by polarographic means A61B5/1486 takes precedence
• CPC Class Codes: A61B 5/1473 invasive, e.g. introduced into the body by a catheter A61B5/1482 takes precedence
• CPC Class Codes: A61B 5/1495 Calibrating or testing of in-vivo probes
• 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

Method and apparatus for providing calibration of analyte sensor including applying a control signal, detecting a measured response to the control signal, determining a variance in the detected measured response, and estimating a sensor sensitivity based on the variance in the detected measured response is provided

Claims

1-20. -20. (canceled)

21. A method of measuring an analyte level, comprising:

calibrating an analyte sensor using an estimated sensor sensitivity, the estimated sensor sensitivity determined based on a variance in a measured response to a control signal applied to the analyte sensor;

receiving a sensor data signal from the analyte sensor; and

determining an analyte level based on the received sensor data signal.

22. The method of claim 21 wherein calibrating the analyte sensor includes applying the control signal that varies over time to the analyte sensor.

23. The method of claim 21 wherein applying the control signal includes opening and closing the current path to the analyte sensor.

24. The method of claim 21 wherein the measured response is determined based on determining one of a working electrode current signal, a counter electrode current signal or a reference electrode current signal.

25. The method of claim 21 wherein the variance in the measured response is determined based on comparing a difference between a beginning of a half duty cycle and an end of the half duty cycle of the measured response to the control signal.

26. The method of claim 21 wherein the estimated sensor sensitivity is determined using a predetermined relationship between sensor sensitivity and the variance in the measured response.

27. The method of claim 21 wherein the estimated sensor sensitivity is determined by retrieving a predetermined sensor sensitivity corresponding to the variance in the measured response.

28. The method of claim 21 further comprising determining if the estimated sensor sensitivity is with a valid range.

29. A system for monitoring analyte concentration, comprising:

an analyte sensor;

a processor operatively coupled to the analyte sensor; and

a memory coupled to the processor, the memory storing processor executable instructions to;

calibrate an analyte sensor using an estimated sensor sensitivity, the estimated sensor sensitivity determined based on a variance in a measured response to a control signal applied to the analyte sensor;

receive a sensor data signal from the analyte sensor; and

determine an analyte level based on the received sensor data signal.

30. The system of claim 29 wherein the instructions to calibrate the analyte sensor includes an instruction to apply the control signal that varies over time to the analyte sensor.

31. The system of claim 29 wherein the instruction to apply the control signal includes an instruction to open and close the current path to the analyte sensor.

32. The system of claim 29 wherein the variance in the measured response is determined by an instruction to compare a difference between a beginning of a half duty cycle and an end of the half duty cycle of the measured response to the control signal.

33. The system of claim 29 wherein the estimated sensor sensitivity is determined by an instruction that uses a predetermined relationship between sensor sensitivity and variance in the measured response.

34. The system of claim 29 wherein the estimated sensor sensitivity is determined by an instruction to retrieve a predetermined sensor sensitivity corresponding to the variance in the measured response.

35. The system of claim 29 wherein the instructions further include an instruction to determine if the estimated sensor sensitivity is within a valid range.

36. An analyte monitoring system comprising:

an on-body device including an analyte sensor and sensor electronics operatively coupled to the sensor; and

a receiver operative to receive sensor data from the on-body device;

wherein the sensor electronics is operative to apply a control signal to the analyte sensor, detect a measured response to the control signal, and transmit the measured response and sensor data to the receiver, and

wherein the receiver is operative to determine a variance in the detected measured response, estimate a sensitivity of the analyte sensor based on the variance in the detected measured response, and determine an analyte level based on the received sensor data.

37. The analyte monitoring system of claim 36, wherein the sensor electronics is configured to vary the level of the control signal over time applied to the sensor.

38. The analyte monitoring system of claim 36, wherein the sensor electronics is operative to apply the control signal by opening and closing the current path to the analyte sensor.

39. The analyte monitoring system of claim 36, wherein the receiver being operative to determine the variance in the detected measured response includes the receiver being operative to compare a difference between a beginning and an end of a half duty cycle of the measured response to the control signal.

40. The analyte monitoring system of claim 36, wherein the receiver being operative to estimate a sensitivity of the sensor includes the receiver being operative to use a predetermined relationship between sensor sensitivity and variance in the measured response.