HEMATOCRIT CORRECTED GLUCOSE MEASUREMENTS FOR ELECTROCHEMICAL TEST STRIP USING TIME DIFFERENTIAL OF THE SIGNALS

摘要

Various embodiments that allow for determination of hematocrit by a time differential between the input and output signals such that a glucose measurement for a blood sample can be corrected by the measured hematocrit of the blood sample.

主权项

1. A method to determine a glucose concentration in a blood sample, the method comprising:
depositing a blood sample in a test chamber of a test strip having at least first and second electrodes in contact with a reagent and third and fourth electrodes not in contact with the reagent; driving a non-oscillating signal to the at least first and second electrodes to cause a reaction with the glucose in the blood sample and the reagent; measuring a current output of the reaction to establish a preliminary glucose concentration; applying a first oscillating input signal at a first frequency to third and fourth electrodes; detecting a first oscillating output signal from the third and fourth electrodes; measuring a first time differential between the first input and output oscillating signals; applying a second oscillating input signal at a second frequency to the third and fourth electrodes; detecting a second oscillating output signal from the third and fourth electrodes; measuring a second time differential between the first input and output oscillating signals; estimating a hematocrit of the blood sample based on the first and second time differentials; and deriving a final glucose concentration based on the preliminary glucose concentration and the hematocrit from the estimating step.