Biosensor for measuring gas and the manufacturing method thereof

• US 5,656,142 A
• Filed: 07/15/1994
• Issued: 08/12/1997
• Est. Priority Date: 07/16/1993
• Status: Expired due to Fees

• Current Assignee: Goldstar Jewellery LLC
• Original Assignee: Goldstar Jewellery LLC
• Inventors: Lee, Hee Jin, Park, Je Kyun
• Primary Examiner(s): Niebling, John
• Assistant Examiner(s): Bell, Bruce F.
• Application Number:
  US08/276,097
• Time in Patent Office: 1,124 Days
• Field of Search: 204/403, 204/412, 204/418, 204/415, 204/435, 204/414, 435/817, 435/291, 435/288
• US Class Current: 204/403.1
• CPC Class Codes: C12Q 1/002 Electrode membranes
• CPC Class Codes: Y10S 435/817 Enzyme or microbe electrode

Abstract

A biosensor for measuring gas-phase organic chemicals rapidly and accurately. The biosensor includes a thick film electrochemical device having an insulating substrate, electrodes formed on the substrate, connecting pads for the electrodes and an insulating layer, and a responsive membrane formed on the electrode portion of the electrochemical device. The responsive membrane is provided with a moisture-absorbing gel layer in which an enzyme for reacting with the gas-phase organic chemical is immobilized.

Claims

1. A biosensor for measuring gas, comprising:

a thick film electrochemical device having an insulating substrate, a plurality of electrodes formed on said substrate, a plurality of pads electrically connected to said electrodes, respectively, and an insulating layer; and

a continuous moisture-absorbing electrolyte gel layer formed on said electrodes and, on at least one of said electrodes, said gel electrolyte layer has an enzyme immobilized layer.

2. A biosensor as claimed in claim 1, wherein said plurality of electrodes comprises a working electrode, a counter electrode and a reference electrode.

3. A biosensor as claimed in claim 1, wherein said plurality of electrodes comprises first and second working electrodes and a reference electrode.

4. A biosensor as claimed in claim 3, wherein an enzyme layer is formed only on said first working electrode, and an enzyme-free moisture-absorbing electrolyte gel layer is formed on said enzyme layer, said second working electrode and said reference electrode.

5. A biosensor as claimed in claim 1, wherein said immobilized enzyme consists of an enzyme group of oxidoreductase or hydrolase.

6. A biosensor as claimed in claim 5, wherein said enzyme group is one of alcohol dehydrogenase, carbon monoxide dehydrogenase, formate dehydrogenase and alcohol oxidase.

7. A biosensor as claimed in claim 1, wherein said moisture-absorbing gel layer is made of one of gelatin, polyacrylamide, alginate and agarose.

8. A biosensor as claimed in claim 7, wherein said moisture-absorbing gel layer includes potassium chloride.

9. A method of manufacturing a gas biosensor, comprising the steps of:

preparing a thick film electrochemical device by forming on an insulating substrate a plurality of electrodes, a plurality of pads for electric connection with the electrodes, respectively, and an insulating layer; and

forming a moisture-absorbing gel layer on the thick film electrochemical device by dropping on an electrode portion of the thick film electrochemical device an enzyme-mixed solution in which a moisture-absorbing gel solution and an enzyme solution are mixed together, and drying the dropped enzyme-mixed solution.

10. A method as claimed in claim 9, wherein the enzyme solution is prepared by dissolving an enzyme and a co-enzyme in a buffer solution.

11. A method as claimed in claim 9, wherein the moisture-absorbing gel solution is prepared by dissolving a moisture-absorbing gel such as gelatin in a potassium chloride solution.