Determining blood glucose in a small volume sample receiving cavity and in a short time period

• US 9,017,544 B2
• Filed: 06/27/2013
• Issued: 04/28/2015
• Est. Priority Date: 10/04/2002
• Status: Expired due to Fees

• Current Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Original Assignee: Roche Diagnostics Operations Incorporated (Roche Holding AG), Roche Operations Limited (Roche Holding AG)
• Inventors: Wilsey, Christopher D.
• Primary Examiner(s): Noguerola, Alex
• Application Number:
  US13/929,293
• Publication Number:
  US 20130284610A1
• Time in Patent Office: 670 Days
• Field of Search: 20440301-40315, 205/777.5, 205/78, 205/792
• US Class Current: 205/792
• CPC Class Codes: C12Q 1/006 for glucose
• 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 27/3275 Sensing specific biomolecules, e.g. nucleic acid strands, based on an electrode surface reaction

Abstract

The concentration of glucose in a blood sample is determined by methods utilizing test strips having a sample receiving cavity having a volume from about 0.3 μl to less than 1 μl and determining the glucose concentration within a time period from about 3.5 seconds to about 8 seconds.

Claims

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

providing a disposable, electrochemical biosensor test strip including a sample receiving cavity having a volume from about 0.3 μ

l to less than about 1 μ

l, and a reagent within the sample receiving cavity, the reagent including an enzyme and a mediator;

applying a blood sample containing glucose into the sample receiving cavity and into contact with the reagent to cause the blood sample to at least partially solubilize or hydrate the reagent, the glucose reacting with the reagent to produce an electroactive reaction product;

detecting the blood sample in the sample receiving cavity;

following said detecting, electrooxidizing the electroactive reaction product, said electrooxidizing producing an assay current;

within the time period from about 3.5 seconds to about 8 seconds after said detecting, measuring the assay current at one or more times and thereby obtaining one or more assay current measurements; and

within the time period from about 3.5 seconds to about 8 seconds after said detecting, determining the concentration of glucose in the blood sample using the one or more assay current measurements.

2. The method of claim 1, wherein said determining comprises determining the concentration of glucose in the blood sample for any glucose concentration in the range of 50-600 mg glucose/dL of blood.

3. The method of claim 1, wherein said determining comprises determining the concentration of glucose in the blood sample for any Hct level in the range of 20-70% Hct.

4. The method of claim 1, wherein the sample receiving cavity has a height of at least 100 μ

m.

5. The method of claim 1, wherein said determining comprises determining the concentration of glucose in the blood sample for any glucose concentration in the range of 50-600 mg glucose/dL of blood and for any Hct level in the range of 20-70% Hct.

6. The method of claim 5, wherein the sample receiving cavity has a height of at least 100 μ

m.

7. The method of claim 1, wherein the sample receiving cavity has a volume from about 0.3 μ

l to about 0.6 μ

l.

8. The method of claim 7, wherein said determining comprises determining the concentration of glucose in the blood sample for any glucose concentration in the range of 50-600 mg glucose/dL of blood and for any Hct level in the range of 20-70% Hct.

9. The method of claim 7, wherein the sample receiving cavity has a height of at least 100 μ

m.