Biosensor and method for quantitating biochemical substrate using the same

• US 5,922,188 A
• Filed: 03/07/1997
• Issued: 07/13/1999
• Est. Priority Date: 03/12/1996
• Status: Expired due to Fees

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Yamamoto, Tomohiro, Ikeda, Shin, Joko, Shigeki, Yoshioka, Toshihiko, Nankai, Shiro, Iwata, Junko
• Primary Examiner(s): Warden, Robert
• Assistant Examiner(s): NOGUEROLA, ALEXANDER STEPHAN
• Application Number:
  US08/812,602
• Time in Patent Office: 858 Days
• Field of Search: 204/403, 205/777.5, 205/792, 435/817
• US Class Current: 205/777.5
• CPC Class Codes: C12Q 1/004 mediator-assisted
• CPC Class Codes: Y10S 435/817 Enzyme or microbe electrode

Abstract

A biosensor includes: an insulating substrate; an electrode system formed on the insulating substrate which has a working electrode and a counter electrode; and a reaction layer formed on the insulating substrate which contains an oxidoreductase and an electron acceptor. The electron acceptor is ferricinium ion derived from ferrocene electrolyte.

Claims

1. A biosensor comprising:

an insulating substrate;

an electrode system formed on the insulating substrate which comprises a working electrode and a counter electrode; and

a reaction layer formed on the insulating substrate which contains an oxidoreductase and a ferrocene electrolyte as an electron acceptor,

wherein the ferrocene electrolyte consists of a ferricinium ion and a mono-anion and the ferrocene electrolyte is selected from the group consisting of ferricinium hexafluorophosphate and ferricinium tetrafluoroborate.

2. A biosensor according to claim 1, wherein the reaction layer further comprises at least one surfactant.

3. A biosensor according to claim 1, wherein the reaction layer further comprises at least one hydrophilic polymer.

4. A biosensor according to claim 1, wherein the oxidoreductase is selected from the group consisting of glucose oxidase;

glucose dehydrogenase;

lactate oxidase;

lactate dehydrogenase;

uricase;

cholesterol oxidase;

a combination of cholesterol oxidase and cholesterol esterase;

a combination of glucose oxidase and invertase;

a combination of glucose oxidase, invertase and mutarotase; and

a combination of fructose dehydrogenase and invertase.

5. A method for quantitating the concentration of a biochemical substrate in a sample liquid by using a biosensor comprising an insulating substrate, an electrode system formed on the insulating substrate which has a working electrode and a counter electrode and a reaction layer provided on the insulating substrate which contains an oxidoreductase and a ferrocene electrolyte as an electron acceptor, comprising the steps of:

adding the sample liquid to the reaction layer; and

detecting a response current value by applying a voltage between the working electrode and the counter electrode, wherein

the ferrocene electrolyte consists of a ferricinium ion and a mono-anion and the ferrocene electrolyte is selected from the group consisting of ferricinium hexafluorophosphate and ferricinium tetrafluoroborate.

6. A method according to claim 5, wherein the reaction layer further comprises at least one surfactant.

7. A method according to claim 5, wherein the reaction layer further comprises at least one hydrophilic polymer.

8. A method according to claim 5, wherein the oxidoreductase is selected from the group consisting of glucose oxidase;

glucose dehydrogenase;

lactate oxidase;

lactate dehydrogenase;

uricase;

cholesterol oxidase;

a combination of cholesterol oxidase and cholesterol esterase;

a combination of glucose oxidase and invertase;

a combination of glucose oxidase, invertase and mutarotase; and

a combination of fructose dehydrogenase and invertase.

9. A method according to claim 5, wherein the biochemical substrate is selected from the group consisting of glucose, cholesterol, lactic acid, uric acid and sucrose.