Biosensor, biosensor chip and biosensor device

• US 8,496,794 B2
• Filed: 05/25/2012
• Issued: 07/30/2013
• Est. Priority Date: 07/02/2002
• Status: Expired due to Term

• Current Assignee: PHC Holdings Corporation
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Ueno, Hiroya, Nakatsuka, Junji
• Primary Examiner(s): Noguerola, Alex
• Application Number:
  US13/481,413
• Publication Number:
  US 20120234677A1
• Time in Patent Office: 431 Days
• Field of Search: 204/400, 20440301-40315, 204/406, 204/416, 204/424, 422 8201- 8203
• US Class Current: 204/403.02
• CPC Class Codes: C12Q 1/001 Enzyme electrodes
• CPC Class Codes: G01N 27/30 Electrodes, e.g. test electrodes; Half-cells G01N27/414 takes precedence
• CPC Class Codes: G01N 27/307 Disposable laminated or multilayered electrodes G01N27/3272 takes precedence
• CPC Class Codes: G01N 27/327 Biochemical electrodes , e.g. electrical or mechanical details for in vitro measurements
• CPC Class Codes: G01N 27/3271 Amperometric enzyme electrodes for analytes in body fluids, e.g. glucose in blood amperometry per se G01N27/49; aspects concerning the enzyme reagent C12Q1/001
• 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 27/3273 Devices therefor, e.g. test element readers, circuitry details not specific to biochemical electrodes G01N33/4875
• CPC Class Codes: G01N 27/416 Systems G01N27/27 takes precedence
• CPC Class Codes: G01R 19/0092 measuring current only all subgroups of G01R19/00 take precedence

Abstract

A biosensor includes a working electrode 101, a counter electrode 102 opposing the working electrode 101, a working electrode terminal 103 and a working electrode reference terminal 10 connected to the working electrode 101 by wires, and a counter electrode terminal 104 connected to the counter electrode 102 by a wire. By employing a structure with at least three electrodes, it is possible to assay a target substance without being influenced by the line resistance on the working electrode side.

Claims

1. A measurement circuit for assaying a concentration of an assayed substance, the measurement circuit comprising:

a voltage application circuit for generating an output voltage, the voltage application circuit comprising a first input for receiving a first voltage from external to the measurement circuit and a second input; and

a voltage source for supplying a second voltage to the second input of the voltage application circuit;

wherein the voltage application circuit generates the output voltage based on at least the first voltage and the second voltage.

2. The measurement circuit of claim 1, wherein the first voltage is substantially equal to the second voltage.

3. The measurement circuit of claim 1, wherein the first input of the voltage application circuit has a high input impedance.

4. The measurement circuit of claim 3, wherein the output voltage and the first input of the voltage application circuit are each coupled to a biosensor.

5. The measurement circuit of claim 4, wherein substantially no current flows from the biosensor to the first input of the voltage application circuit during an assay.

6. The measurement circuit of claim 4, wherein the measurement circuit further generates a current level signal that is representative of a level of a current that flows in the biosensor during an assay.

7. The measurement circuit of claim 6, further comprising a signal processing circuit for processing the current level signal.

8. A measurement circuit for assaying a concentration of an assayed substance, the measurement circuit comprising:

a voltage application circuit for generating an output voltage, the voltage application circuit comprising a first input for receiving a first voltage from external to the measurement circuit, wherein the first input has a high input impedance, and a second input; and

a voltage source for supplying a second voltage to the second input of the voltage application circuit;

wherein the voltage application circuit generates the output voltage such that the first voltage is substantially equal to the second voltage.

9. The measurement circuit of claim 8, wherein the output voltage and the first input of the voltage application circuit are each coupled to a biosensor.

10. The measurement circuit of claim 9, wherein substantially no current flows from the biosensor to the first input of the voltage application circuit during an assay.

11. The measurement circuit of claim 9, wherein the measurement circuit further generates a current level signal that is representative of a level of a current that flows in the biosensor during an assay.

12. The measurement circuit of claim 11, further comprising a signal processing circuit for processing the current level signal.