Glucose sensor measurement

• US 5,215,887 A
• Filed: 12/02/1991
• Issued: 06/01/1993
• Est. Priority Date: 11/30/1990
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Saito, Atsushi
• Primary Examiner(s): Wityshyn, Michael G.
• Assistant Examiner(s): Leary, Louise N.
• Application Number:
  US07/801,657
• Time in Patent Office: 547 Days
• Field of Search: 435/14, 435/4, 435/25, 435/174, 435/182, 204/403, 204/412, 204/418, 204/817, 204/195
• US Class Current: 435/14
• CPC Class Codes: C12N 11/02 Enzymes or microbial cells immobilised on or in an organic carrier
• CPC Class Codes: C12Q 1/006 for glucose

Abstract

Disclosed is a method of measuring glucose concentration of a sample solution using a glucose sensor having an ion-sensitive field-effect transistor which can detect pH change in the sample solution provided with a glucose oxidase-immobilized film formed on the ion-sensing section thereof, which comprise a step of measuring the output of the glucose sensor under a low level of dissolved oxygen in the enzyme-immobilized film; a step of measuring the output of the glucose sensor under a high level of dissolved oxygen in the enzyme-immobilized film; and a step of determining the glucose concentration of the sample solution from the difference between said two output values. The measuring system can be simplified and working efficiency can be improved since the present measuring method requires neither a buffer nor correct measuring of the sample solution or buffer.

Claims

1. A method of measuring glucose concentration of a sample solution using a glucose sensor having an ion-sensitive field-effect transistor which can detect pH change in the sample solution and is provided with a glucose oxidase-immobilized film formed on an ion-sensing section thereof, which comprises:

a step of measuring the output of the glucose sensor under a low level of dissolved oxygen in the glucose oxidase immobilized film;

a step of measuring the output of the glucose sensor under a high level of dissolved oxygen in the glucose oxidase immobilized film; and

a step of determining the glucose concentration of the sample solution from the difference between the two measured outputs.

2. A method of measuring glucose concentration of a sample solution using a glucose sensor having an ion-sensitive field-effect transistor which can detect pH change in the sample solution and is provided with a glucose oxidase-immobilized film formed on an ion-sensing section thereof, which comprises;

a step of measuring the output of the glucose sensor under a low level of dissolved oxygen in the glucose oxidase immobilized film by exposing the sample solution to a gaseous atmosphere having an oxygen content lower than in air;

a step of measuring the output of the glucose sensor under a high level of dissolved oxygen in the glucose enzyme-immobilized film by exposing the sample solution to air; and

a step of determining the glucose concentration of the sample solution from the difference between the two measured outputs.

3. A method of measuring glucose concentration of a sample solution using a glucose sensor having an ion-sensitive field-effect transistor which can detect pH change in the sample solution and is provided with a glucose oxidase-immobilized film formed on an ion-sensing section thereof, which comprises:

a step of measuring the output of the glucose sensor under a low level of dissolved oxygen in the glucose oxidase immobilized film by exposing the sample solution to air;

a step of measuring the output of the glucose sensor under a high level of dissolved oxygen in the glucose oxidase immobilized film by exposing the sample solution to a gaseous atmosphere having an oxygen content higher than in air; and

a step of determining the glucose concentration of the sample solution from the difference between the two measured outputs.

4. A method of measuring glucose concentration of a sample solution using a glucose sensor having an ion-sensitive field-effect transistor which can detect pH change in the sample solution and is provided with a glucose oxidase-immobilized film formed on an ion-sensing section thereof, which comprises:

a step of measuring the output of the glucose sensor by dipping the glucose sensor in the sample solution under a low level of dissolved oxygen in the glucose oxidase immobilized film;

a step of measuring the output of the glucose under a high level of dissolved oxygen in the glucose oxidase immobilized film by exposing the glucose sensor to a gaseous atmosphere containing oxygen; and

a step of determining the glucose concentration of the sample solution from the difference between the two measured outputs.