Method of determining an analyte concentration

• US 10,150,981 B2
• Filed: 06/01/2016
• Issued: 12/11/2018
• Est. Priority Date: 12/10/2007
• Status: Active Grant

• Current Assignee: Ascensia Diabetes Care Holdings AG (PHC Holdings Corporation)
• Original Assignee: Ascensia Diabetes Care Holdings AG (PHC Holdings Corporation)
• Inventors: Zhu, Boru
• Primary Examiner(s): Yamasaki, Robert J
• Assistant Examiner(s): Constantine, Charles Zoltan
• Application Number:
  US15/170,368
• Publication Number:
  US 20160273019A1
• Time in Patent Office: 923 Days
• Field of Search: None
• CPC Class Codes: C12N 11/14 Enzymes or microbial cells immobilised on or in an inorganic carrier
• CPC Class Codes: C12Q 1/002 Electrode membranes
• CPC Class Codes: C12Q 1/004 mediator-assisted
• CPC Class Codes: C12Q 1/006 for glucose
• CPC Class Codes: C12Q 1/26 involving oxidoreductase
• CPC Class Codes: C12Q 1/54 involving glucose or galactose
• CPC Class Codes: G01N 27/3272 Test elements therefor, i.e. disposable laminated substrates with electrodes, reagent and channels optical biosensors G01N33/52
• CPC Class Codes: G01N 27/3273 Devices therefor, e.g. test element readers, circuitry details not specific to biochemical electrodes G01N33/4875
• CPC Class Codes: G01N 33/5438 Electrodes

Abstract

A reagent composition for a biosensor sensor strip is disclosed that provides for rapid rehydration after drying. The composition includes porous particles and is preferably formed as a colloidal suspension. The dried reagent composition including porous particles may provide analytically useful output from the sensor strip in a shorter time period than observed from dried reagent compositions using solid particles. The output signal from the porous particle compositions may be correlated to the analyte concentration of a sample within about two seconds. In this manner, an accurate concentration determination of an analyte concentration in a sample may be obtained in less time than from sensor strips including conventional compositions. The reagent composition including the porous particles also may allow for the redox reaction between the reagents and the analyte to reach a maximum kinetic performance in a shorter time period than observed from conventional sensor strips.

Claims

1. A method of determining the concentration of an analyte in a sample, the method comprising:

introducing the sample including the analyte to a reagent composition, the reagent composition comprising porous particles with a plurality of pores having an average diameter from 0.05 micrometer to 10 micrometer and a void volume of at least 20% (v/v), an electron transfer mediator and an enzyme;

applying an input signal to the sample that has been introduced to the reagent composition;

measuring at least one output signal current value within less than 3 seconds of introducing the sample to the reagent composition; and

determining the concentration of the analyte in the sample from the at least one output signal current value.

2. The method of claim 1, wherein measuring the at least one output signal current value is within about 1.7 to about 2.7 seconds of introducing the sample to the reagent composition.

3. The method of claim 1, wherein the analyte comprises glucose and wherein the sample comprises whole blood.

4. The method of claim 1, wherein the at least one output signal current value is at least two output signal current values.

5. The method of claim 1, wherein the input signal includes at least one pulse interval including an excitation and a relaxation.

6. The method of claim 1, further comprising measuring the at least one output signal current value using a maximum kinetic performance of a redox reaction between the reagent composition and the analyte, the maximum kinetic performance being determined with a gated amperometric pulse sequence having at least five duty cycles.

7. The method of claim 1, wherein the reagent composition further comprises at least one polymeric material.

8. The method of claim 1, wherein the porous particles have an average diameter from 0.1 to 5 micrometers (μ

m).

9. The method of claim 1, wherein the porous particles have a void volume of at least 40% (v/v).

10. The method of claim 1, wherein the plurality of pores is sized to exclude the enzyme.

11. The method of claim 1, wherein the plurality of pores is less than about 5 nanometers.

12. The method of claim 1, wherein the porous particles comprise silica or zeolite.

13. The method of claim 1, wherein the reagent composition includes from about 0.5 to about 10% (w/w) of the mediator.

14. The method of claim 1, wherein the enzyme is glucose dehydrogenase.

15. The method of claim 1, wherein the enzyme is glucose oxidase.

16. A method of determining the concentration of glucose in a sample, the method comprising:

introducing the sample including glucose to a reagent composition, the reagent composition comprising porous particles with a plurality of pores having an average diameter from 0.05 micrometer to 10 micrometer and a void volume of at least 20% (v/v), an electron transfer mediator, an enzyme and at least one polymeric material;

applying an input signal to the sample that has been introduced to the reagent composition;

measuring at least one output signal current value within less than 3 seconds of introducing the sample to the reagent composition; and

determining the concentration of the glucose in the sample from the at least one output signal current value.