System and Methods for Determining an Analyte Concentration Incorporating a Hematocrit Correction

Abstract

Methods and devices for determining the concentration of a constituent in a physiological sample are provided. The blood sample is introduced into a test strip with portions of the blood sample being directed to both a first capillary and a second capillary. The first capillary configured to electrochemically determine a concentration of a first analyte in a blood sample by measuring a signal across a set of electrodes. The second capillary is configured to determine a hematocrit value of the blood sample by measuring a signal across a second set of electrodes.

Description

[0001] This application claims priority to U.S. Provisional Patent Application No. 60 / 842,032, filed Sep. 5, 2006, the content of which is incorporated herein by reference.DESCRIPTION OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to the field of diagnostic testing systems for measuring the concentration of an analyte in a blood sample and, more particularly, to methods for measuring an analyte concentration that incorporates a hematocrit correction. [0004] 2. Background of the Invention [0005] The present disclosure relates to a biosensor system for measuring an analyte in a bodily fluid, such as blood, wherein the system comprises a unique process and system for correcting inaccuracies in sample concentration measurements. For example, the present disclosure provides methods of correcting analyte concentration measurements of bodily fluids. [0006] Electrochemical sensors have long been used to detect and / or measure the presence of substances...

AI Technical Summary

Benefits of technology

[0019] Another embodiment of the invention is directed to a test card for quality control analysis of biosensors comprising a base layer, wherein the base layer includes a plurality of electrodes. Further, a plurality of partially formed test strips,

Problems solved by technology

Biosensors configured to measure a blood constituent may be affected by the presence of certain blood components that may undesirably affect the measurement and lead to inaccuracies in the detected signal.

This inaccuracy may result in an inaccurate glucose reading, leaving the patient unaware of a potentially dangerous blood sugar level, for example.

As one example, the particular blood hematocrit level (i.e., the percentage of the amount of blood that is occupied by red blood cells) can erroneously affect a resulting analyte concentration measurement.

At high hematocrits, for example, the red blood cells may impede the reaction of enzymes and electrochemical mediators, reduce the rate of chemistry dissolution since there less plasma volume to solvate the chemical reactants, and slow diffusion of the mediator.

These methods have the disadvantages of increasing the cost and complexity of test strips and may undesirably increase the time required to determine an accurate glucose measurement.

Such methods suffer from the increased cost and complexity of advanced meters required for signal filtering and analysis.

Data processing using this technique, however, is complicated because both a hematocrit correction factor and an estimated glucose concentration must be determined to establish the corrected glucose value.

In addition, the time duration of the first step greatly increases the overall test time of the biosensor, which is undesirable from the user's perspective.

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