Method and assembly for determining the temperature of a test sensor

• US 9,874,481 B2
• Filed: 06/30/2014
• Issued: 01/23/2018
• Est. Priority Date: 06/08/2009
• Status: Active Grant

• Current Assignee: Ascensia Diabetes Care Holdings AG (PHC Holdings Corporation)
• Original Assignee: Ascensia Diabetes Care Holdings AG (PHC Holdings Corporation)
• Inventors: Parasnis, Narasinha, Sun, Hoi-Cheong Steve, Wu, Mu
• Primary Examiner(s): Caputo, Lisa
• Assistant Examiner(s): Ahmed, Nasir U
• Application Number:
  US14/319,967
• Publication Number:
  US 20140314117A1
• Time in Patent Office: 1,303 Days
• CPC Class Codes: A61B 2560/0252 using ambient temperature
• CPC Class Codes: A61B 2562/0295 Strip shaped analyte sensors for apparatus classified in A61B5/145 or A61B5/157
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1495 Calibrating or testing of in-vivo probes
• CPC Class Codes: G01K 15/005 Calibration
• CPC Class Codes: G01N 21/8483 Investigating reagent band test-element handling not specific to a test method G01N33/4875; analytical elements specific to chemical analysis of biological material G01N33/52; autometer with reagent band G01N35/04
• CPC Class Codes: G01N 25/00 Investigating or analyzing materials by the use of thermal means G01N3/00 - G01N23/00 take precedence

Abstract

Methods and systems accurately determine an analyte concentration in a fluid sample. In an example embodiment, a receiving port receives a test sensor. The test sensor includes a fluid-receiving area for receiving a fluid sample. The fluid-receiving area contains a reagent that produces a measurable reaction with an analyte in the fluid sample. The test sensor has a test-sensor temperature and the reagent has a reagent temperature. A measurement system measures the reaction between the reagent and the analyte. A temperature-measuring system measures the test sensor temperature when the test sensor is received into the receiving port. A concentration of the analyte in the fluid sample is determined according to the measurement of the reaction and the measurement of the test sensor temperature. A diagnostic system determines an accuracy of the temperature-measuring system. The calculation of the analyte concentration may be adjusted according to the accuracy of temperature-measuring system.

Claims

1. A device for determining an analyte concentration in a fluid sample, comprising:

a receiving port configured to receive a test sensor, the test sensor including a fluid-receiving area for receiving a fluid sample, the fluid-receiving area containing a reagent that produces a measurable reaction with an analyte in the fluid sample, the test sensor having a test-sensor temperature;

a measurement system that measures the reaction between the reagent and the analyte, the measurement system at least partially disposed proximate the receiving port;

a temperature-measuring system at least partially disposed proximate the receiving port, the temperature-measuring system configured to measure the test-sensor temperature when the test sensor is received into the receiving port, a concentration of the analyte in the fluid sample being determined according to the measurement of the reaction and the measurement of the test-sensor temperature; and

a diagnostic system including a reference object at least partially disposed during temperature measurements proximate the receiving port, the reference object achieving a reference temperature, the temperature-measuring system being further configured to measure a plurality of test temperatures of the reference object, the diagnostic system configured to determine a test rate of temperature change of the reference object based on the plurality of test temperatures, and wherein the diagnostic system is further configured to determine an accuracy of the temperature-measuring system based on the plurality of test temperature measurements of the reference object measured by the temperature-measuring system by comparing the test rate of temperature change to an expected rate of temperature change for the reference object.

2. The device of claim 1, wherein the diagnostic system is configured to further determine the accuracy of the temperature-measuring system based on a comparison between at least one test temperature and a threshold value.

3. The device of claim 2, wherein the threshold value is the reference temperature.

4. The device of claim 1, wherein the reference object is disposed on a calibration device that is removably inserted into the receiving port.

5. The device of claim 1, wherein the reference object includes at least one of a resistor or a light emitting diode (LED).

6. The device of claim 1, further comprising a cooling element configured to cool the reference object to the reference temperature.

7. The device of claim 1, wherein the temperature-measuring system includes a plurality of temperature-measuring systems disposed at different locations within the device.

8. A method for testing a meter, the meter determining an analyte concentration in a fluid sample collected on a test sensor by measuring a reaction between the analyte and a reagent on the test sensor, the meter including a temperature-measuring system that determines a test-sensor temperature, the meter using the test-sensor temperature as a parameter in determining the analyte concentration, the method comprising:

changing a temperature of a reference object to a reference temperature, the reference object being positioned in the meter for measurement by the temperature-measuring system;

determining, via the temperature-measuring system, a plurality of test temperatures for the reference object during or after the changing the temperature of the reference object and determining a test rate of temperature change of the reference object based on the plurality of test temperatures; and

determining an accuracy of the temperature-measuring system based on the plurality of test temperatures by comparing the test rate of temperature change to an expected rate of temperature change for the reference object.

9. The method of claim 8, wherein the determining the accuracy further includes comparing the reference temperature to one or more of the plurality of test temperatures determined after the reference object achieves the reference temperature.

10. The method of claim 8, further comprising calibrating the temperature-measuring system based on determined accuracy of the temperature-measuring system.

11. The method of claim 10, wherein the calibrating occurs at a time after the manufacture and assembly of the meter.

12. The method of claim 10, wherein the determining the accuracy and the calibrating occur automatically on a periodic basis.

13. The method of claim 10, wherein the calibrating includes correcting for one or more offset or gain errors associated with a signal generated by a temperature sensor of the temperature-measuring system.

14. The method of claim 8, wherein the temperature-measuring system includes a temperature sensor, a pre-amplifier, and a memory as an integrated unit prior to installation of the temperature-measuring system into the meter.

15. The method of claim 8, further comprising receiving a calibration device in a receiving port of the meter, the calibration device including the reference object.

16. The method of claim 8, wherein the reference object is integral with the meter adjacent to a receiving port, the test sensor being configured to be removably inserted in the receiving port.

17. The method of claim 8, wherein the changing the temperature of the reference object includes heating a temperature sensor of the temperature-measuring system.

18. A device for determining an analyte concentration in a fluid sample, comprising:

a receiving port including a window, the receiving port configured to receive a test sensor, the test sensor including a fluid-receiving area for receiving a fluid sample, the fluid-receiving area containing a reagent that produces a measurable reaction with an analyte in the fluid sample, the test sensor having a test-sensor temperature;

a measurement system that measures the reaction between the reagent and the analyte, the measurement system at least partially disposed proximate the receiving port;

a temperature-measuring system at least partially disposed proximate the receiving port, the temperature-measuring system including a temperature sensor, the temperature-measuring system configured to measure the test-sensor temperature when the test sensor is received into the receiving port, a concentration of the analyte in the fluid sample being determined according to the measurement of the reaction and the measurement of the test-sensor temperature; and

a diagnostic system including a reference object at least partially disposed during temperature measurements proximate the receiving port, the reference object achieving a reference temperature, the temperature-measuring system further configured to measure at least one test temperature of the reference object, the diagnostic system configured to determine an accuracy of the temperature-measuring system based on the at least one test temperature measurement of the reference object measured by the temperature-measuring system,

wherein the receiving port, the temperature-measuring system, and the diagnostic system are configured to allow the temperature-measuring system to measure the test-sensor temperature when the test sensor is received in the receiving port and measure the at least one test temperature of the reference object when the test sensor is not received in the receiving port, the temperature sensor and the reference object being disposed on opposing sides of the window such that the temperature sensor is configured to measure the at least one test temperature of the reference object through the window when the test sensor is not received in the receiving port.