Analyte measurement method and system

Patent metadata

Field	Value
Publication number	US-9500618-B2
Application number	US-201514606317-A
Country	US
Kind code	B2
Filing date	Jan 27, 2015
Priority date	Mar 31, 2010
Publication date	Nov 22, 2016
Grant date	Nov 22, 2016

Abstract

Described and illustrated herein are systems and exemplary methods of operating an analyte measurement system having a meter and a test strip. In one embodiment, the method may be achieved by applying a first test voltage between a reference electrode and a second working electrode and applying a second test voltage between the reference electrode and a first working electrode; measuring a first test current, a second test current, a third test current and a fourth test current at the second working electrode after a blood sample containing an analyte is applied to the test strip; measuring a fifth test current at the first working electrode; estimating a hematocrit-corrected analyte concentration from the first, second, third, fourth and fifth test currents; and annunciating the hematocrit-corrected analyte concentration.

First claim

What is claimed is:

1. A method for determining a glucose concentration measurable with a system having a test strip and a meter, the method comprising:
applying a first test voltage between a reference electrode and a second working electrode coated with a reagent layer and applying a second test voltage between a reference electrode and a first working electrode coated with a reagent layer;
measuring a first test current, a second test current, a third test current and a fourth test current at the second working electrode after a blood sample containing glucose is applied to the test strip;
measuring a fifth test current at the first working electrode;
determining the glucose concentration from the first, second, third, fourth and fifth test currents with an equation of the form:

G
=

[

(

I
1

I
2

)

(

a
-

b
⁢

I
3

I
4

)

⁢

xI
5

]

-
intercept

slope

where:
G is the glucose concentration;
I 1 is the first test current;
I 2 is the second test current;
I 3 is the third test current;
I 4 is the fourth test current;
I 5 is the fifth test current;
a is a first tuning parameter and b is a second tuning parameter.

2. The method of claim 1 , in which first tuning parameter is from about 9.9 to about 10.2 and second tuning parameter is from about 10.8 to about 11.2.

3. A method for determining a hematocrit-corrected test current measurable with a system having a test strip and a meter, the method comprising:
applying a first test voltage between a reference electrode and a second working electrode coated with a reagent layer and applying a second test voltage between a reference electrode and a first working electrode coated with a reagent layer;
measuring a first test current, a second test current, a third test current and a fourth test current at the second working electrode after a blood sample containing glucose is applied to the test strip;
measuring a fifth test current at the first working electrode; and
determining the hematocrit-corrected test current by determining a ratio of the first test current to the second test current raised to a power term and multiplying the ratio by the fifth test current, where the power term is a function of a first tuning parameter and a second tuning parameter.

4. The method of claim 3 , in which first tuning parameter is from about 31 to 33 and second tuning parameter is from about 53 to about 55; the first test current comprises a current measured from about 0.9 to about 1.0 seconds after initiation of the measuring; the second current comprises a current measured from about 1.1 to about 2.0 seconds after initiation of the measuring; the third current comprises a current measured from about 2.4 to about 2.5 seconds after initiation of the measuring; the fourth current comprises a current measured from about four 2.61 to about 2.63 seconds after initiation of the measuring; the fifth current comprises a current measured from about 2.70 to about 2.72 seconds after initiation of the measuring.

5. The method of claim 3 , in which no test voltage is applied for a period of time after the deposition of the physiological fluid to provide for a reaction time before application of the test voltage.

6. The method of claim 5 , in which the first test current is measured from about 3.37 to about 3.39 seconds after a reaction period of time; the second current is measured from about 3.46 to about 3.48 seconds after a reaction period of time; the third current is measured from about 3.54 to about 3.56 seconds after a reaction period of time; the fourth current is measured from about 4.05 to about 4.07 seconds after a reaction period of time; the fifth current is measured from about 4.08 to about 4.10 seconds after a reaction period of time.

7. The method of claim 6 , in which the reference electrode, the first electrode and the second electrodes are disposed on one plane.

Assignees

• Lifescan Scotland Ltd

Inventors

• Malecha Michael
• Craggs Adam

Classifications

• G01N27/3272

  Test elements therefor, i.e. disposable laminated substrates with electrodes, reagent and channels (optical biosensors G01N33/52) · CPC title

• G01N27/416

  Systems (G01N27/27 takes precedence) · CPC title

• G01N27/3273 Primary

  Devices therefor, e.g. test element readers, circuitry (details not specific to biochemical electrodes G01N33/4875) · CPC title

• G01N27/3274 Primary

  Corrective measures, e.g. error detection, compensation for temperature or hematocrit, calibration (coding of calibration information G01N33/48771) · CPC title

• G01N33/49

  Blood {(chemical methods for determining blood cell populations G01N33/5094; chemical analysis of blood groups or blood types G01N33/80)} · CPC title