Test method and test device for analysing a body fluid

• US 10,244,970 B2
• Filed: 08/12/2016
• Issued: 04/02/2019
• Est. Priority Date: 02/18/2009
• Status: Active Grant

• Current Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Original Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Inventors: Miltner, Karl, Lorenz, Robert, Porsch, Ulrich, Knapp, Clemens
• Primary Examiner(s): Warden, Jill A
• Assistant Examiner(s): Handy, Dwayne K
• Application Number:
  US15/235,154
• Publication Number:
  US 20160349187A1
• Time in Patent Office: 963 Days
• Field of Search: 436164, 436169, 600365
• CPC Class Codes: A61B 2560/0223 of calibration, e.g. protocols for calibrating sensors
• 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 5/1455 using optical sensors, e.g. spectral photometrical oximeters
• CPC Class Codes: G01N 2021/8488 the band presenting reference patches
• CPC Class Codes: G01N 2021/8494 Measuring or storing parameters of the band
• CPC Class Codes: G01N 2035/0491 Position sensing, encoding; closed-loop control
• 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 2201/062 LED's
• CPC Class Codes: G01N 2201/13 Standards, constitution
• CPC Class Codes: G01N 35/00009 provided with a sample supporting tape, e.g. with absorbent zones

Abstract

There is provided a test method for analyzing a body fluid in which a test tape is used in a test device to successively provide analytical test fields stored on the test tape, wherein body fluid is applied by a user to the test field provided at a time and the said test field is photometrically scanned using a measuring unit of the device to record measurement signals. To increase the measurement reliability, it is proposed that a control value is determined from a time-dependent and/or wavelength-dependent change in the measurement signals and that the measurement signals are processed as valid or discarded as erroneous depending on the control value.

Claims

1. A method of detecting reagent layer failure on a test tape having a plurality of test fields, the method comprising the steps of:

providing an unused test field of the test tape to initiate a test, wherein the test tape is in a test device having a measuring unit comprising at least one radiation source to generate at least one wavelength of light and a photodiode for reflection-photometric signal detection of the at least one wavelength of light;

photometrically scanning the unused test field with the measuring unit and detecting relative remission measurement signals of the at least one wavelength of light generated by the at least one radiation source over a duration of a waiting time prior to applying a body fluid sample to the unused test field;

calculating a control value based upon a blank measurement signal difference between relative remissions detected at a beginning and at an end of the waiting time; and

detecting a reagent layer failure and discarding the test if the control value is above zero and below a preset threshold.

2. The method of claim 1, wherein the reagent layer failure results from environmental reagent layer deterioration due to at least one of heat, humidity and sunlight.