Method for determining whether a disposable, dry regent, electrochemical test strip is unsuitable for use
View Patent ↗A method of measuring an analyte in a biological fluid comprises applying an excitation signal having a DC component and an AC component. The AC and DC responses are measured; a corrected DC response is determined using the AC response; and a concentration of the analyte is determined based upon the corrected DC response. Other methods and devices are disclosed.
1. A method for detecting whether a disposable, dry reagent, electrochemical test strip is unsuitable for use in determining a concentration of a medically significant component of a biological fluid, comprising:
a) applying a signal to the tests trip before dosing the test strip, the test strip including a pair of measurement electrodes and a dry reagent, the signal having an AC component, the signal being applied between the measurement electrodes of the test strip;
b) measuring an AC response to the signal; and
c) using the AC response to determine if the test strip is unsuitable for use.
2. The method of claim 1 , wherein the AC response comprises an admittance.
3. The method of claim 1 , wherein the signal is an AC signal.
4. The method of claim 1 , wherein the AC response comprises magnitude information.
5. The method of claim 1 , wherein the AC component of the signal has a frequency not less than 1 Hz and not greater than 20 kHz.
6. The method of claim 1 , wherein the biological fluid is blood.
7. The method of claim 1 , wherein the method is automatically performed at a predetermined time.
8. The method of claim 1 in which said using comprises calculating an impedance level and determining if the impedance value is characteristic of a test strip having a level of current leakage prior to dosing which indicates that the test strip is not suitable for testing for analyte.
9. The method of claim 8 in which said determining comprises determining if the impedance value is characteristic of a test strip which has been exposed to an excessive amount of water.