Biosensor, thin film electrode forming method, quantification apparatus, and quantification method

• US 8,741,124 B2
• Filed: 02/27/2013
• Issued: 06/03/2014
• Est. Priority Date: 11/15/1999
• Status: Expired due to Fees

• Current Assignee: PHC Holdings Corporation
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Miyazaki, Shoji, Tokunaga, Hiroyuki, Fujiwara, Masaki, Yamanishi, Eriko, Tokuno, Yoshinobu
• Primary Examiner(s): Noguerola, Alex
• Application Number:
  US13/778,738
• Publication Number:
  US 20130306494A1
• Time in Patent Office: 461 Days
• Field of Search: 20440301-40315, 205/777.5, 205/78, 205/792, 205/775
• US Class Current: 205/775
• CPC Class Codes: C12Q 1/001 Enzyme electrodes
• 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 33/48771 Coding of information, e.g. calibration data, lot number
• CPC Class Codes: Y10T 29/49002 Electrical device making

Abstract

A biosensor is disclosed comprising a support; a conductive layer composed of an electrical conductive material such as a noble metal, for example gold or palladium, and carbon; slits parallel to and perpendicular to the side of the support; working, counter, and detecting electrodes; a spacer which covers the working, counter, and detecting electrodes on the support; a rectangular cutout in the spacer forming a specimen supply path; an inlet to the specimen supply path; a reagent layer formed by applying a reagent containing an enzyme to the working, counter, and detecting electrodes, which are exposed through the cutout in the spacer; and a cover over the spacer. The biosensor can be formed by a simple method, and provides a uniform reagent layer on the electrodes regardless of the reagent composition.

Claims

1. A method of quantifying an analyte in a liquid sample, comprising the steps of:

providing a sensor comprising;

a working electrode;

a terminal associated with the working electrode;

a counter electrode;

a terminal associated with the counter electrode;

a detection electrode; and

a terminal associated with the detection electrode;

identifying the sensor type by applying a first voltage between two points on the same electrode; and

quantifying the analyte in the liquid sample by applying a second voltage between the working electrode and the counter electrode;

wherein the sensor remains in the same position in the identifying and quantifying steps.

2. The method of claim 1, wherein each of the electrodes and the terminals comprises a noble metal selected from the group consisting of palladium, platinum, gold, ruthenium, and a combination thereof.

3. The method of claim 1, wherein the sensor further comprises:

an insulating support on which the electrodes and the terminals are formed;

a reagent layer formed on the electrodes;

a spacer layer provided on the reagent layer where the spacer layer defines a supply path for bringing the sample liquid into contact with the reagent layer; and

a cover provided on the spacer layer.

4. The method of claim 1, wherein each of the electrodes and the terminals has a thickness from 3 nm to 1000 nm.

5. The method of claim 1, wherein each of the electrodes is separated by 0.005 mm to 0.3 mm.

6. The method of claim 1, wherein the working electrode is surrounded by the counter electrode.

7. The method of claim 1, wherein the sensor further comprises:

a first insulating support,

a second insulating support, and

a supply path comprising an inlet for introducing the liquid sample;

wherein the electrodes and the supply path comprising the inlet are situated between the first insulating support and the second insulating support.

8. The method of claim 7, wherein the sensor further comprises:

a reagent layer for quantifying the analyte in the liquid sample,

wherein the reagent layer is positioned on at least a portion of the electrodes, and

wherein the supply path brings the liquid sample into contact with the reagent layer.

9. The method of claim 1, wherein the sensor further comprises:

an insulating support,

a cover, and

a spacer layer comprising an inlet situated between the insulating support and the cover;

wherein the spacer layer defines a supply path for introducing the liquid sample.

10. The method of claim 9, wherein the sensor further comprises:

a reagent layer for quantifying the analyte in the liquid sample,

wherein the reagent layer is positioned on at least a portion of the electrodes, and

wherein the supply path brings the liquid sample into contact with the reagent layer.