Biosensor

• US 20110259741A1
• Filed: 04/21/2011
• Published: 10/27/2011
• Est. Priority Date: 04/22/2010
• Status: Active Grant

• Current Assignee: ARKRAY, Inc
• Original Assignee: ARKRAY, Inc
• Inventors: MURASE, Yosuke, KATSUKI, Koji
• Granted Patent: US 8,679,310 B2
• Time in Patent Office: Days
• US Class Current: 204/403.14
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14865 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors
• CPC Class Codes: A61B 5/7203 for noise prevention, reduction or removal
• CPC Class Codes: C12Q 1/001 Enzyme electrodes
• CPC Class Codes: G01N 27/3274 Corrective measures, e.g. error detection, compensation for temperature or hematocrit, calibration coding of calibration information G01N33/48771

Abstract

A biosensor includes a first working electrode that a biocatalyst, which has a property that reacts on a specified ground substance, is disposed, a second working electrode that the biocatalyst, which the property is lost, is disposed, and at least one counter electrode for respectively applying a voltage to the first working electrode and the second working electrode.

Claims

1. A biosensor comprising:

a first working electrode that a biocatalyst, which has a property that reacts on a specified ground substance, is disposed;

a second working electrode that the biocatalyst, which the property is lost, is disposed; and

at least one counter electrode for respectively applying a voltage to the first working electrode and the second working electrode.

2. The biosensor according to claim 1, wherein the biocatalyst haying the property reacting on the specified ground substance is disposed on the second working electrode, and the property of the biocatalyst is deactivated by providing energy to the second working electrode.

3. The biosensor according to claim 2, wherein the energy includes thermal energy.

4. The biosensor according to claim 2, wherein the energy includes electric energy.

5. The biosensor according to claim 1, wherein the biocatalyst having the property reacting on the specified ground substance is disposed on the second working electrode, and a material for making the biocatalyst lose the property or for inhibiting the property is added.

6. The biosensor according to according to claim 1, wherein the biocatalyst is an enzyme.

7. A biosensor comprising:

a first working electrode that a first biocatalyst, which has a property that reacts on a specified ground substance, is disposed;

a second working electrode that a second biocatalyst, which has the property, is disposed; and

at least one counter electrode for respectively applying a voltage to the first working electrode and the second working electrode,

wherein a reaction speed of the first biocatalyst with the ground substance is different from a reaction speed of the second biocatalyst with the ground substance.

8. The biosensor according to claim 7, wherein the first biocatalyst and said second biocatalyst are enzymes.

9. The biosensor according to claim 8, wherein the second biocatalyst is an enzyme obtained by genetic modification of the first biocatalyst.

10. A biosensor comprising:

a first working electrode that a first biocatalyst, which has a property that reacts on a specified ground substance, is disposed;

a second working electrode that a second biocatalyst, which has the property, is disposed; and

at least one counter electrode for respectively applying a voltage to the first working electrode and the second working electrode,

wherein a reaction area on the first working electrode is different from a reaction area on the second working electrode.

11. A biosensor comprising:

a first working electrode that a first biocatalyst, which has a property that reacts on a specified ground substance, is disposed;

a second working electrode that a second biocatalyst, which has the property, is disposed; and

at least one counter, electrode for respectively applying a voltage to the first working electrode and the second working electrode,

wherein a total reaction activity on the first working electrode is different from a total reaction activity on the second working electrode.

12. A monitoring apparatus comprising:

a first detection unit which detects a first signal value from a first working electrode obtained by applying a voltage to between the first working electrode and a counter electrode, wherein a biocatalyst having a property reacting on a specified ground substance is disposed on the first working electrode;

a second detection unit which detects a second signal value from a second, working electrode obtained, by applying a voltage to between the second working electrode and the counter electrode, wherein the biocatalyst that the property is lost is disposed on the second working electrode;

a correction unit which corrects a concentration of the specified ground substance that is calculated from the first signal value by the second signal value; and

an output unit which outputs the corrected concentration of the specified ground substance.

13. The monitoring apparatus, according to claim 12, wherein the correction unit calculates a value obtained by subtracting the second signal value from the first signal value as the corrected concentration of the specified ground substance.

14. A monitoring apparatus comprising:

a first detection unit, which detects a first signal value from a first working electrode obtained by applying a voltage to between the first working electrode and a counter electrode, wherein a first biocatalyst having a property reacting on a specified ground substance is disposed on the first working electrode;

a second detection unit which detects a second signal value from a second working electrode obtained by applying a voltage to between the second working electrode arid the counter electrode, wherein a second biocatalyst having the property and a reaction speed differing from the first biocatalyst is disposed on the second working electrode;

a correction unit which corrects a concentration of the specified ground substance that is calculated from the first signal value by the second signal value; and

an output-unit which outputs the corrected concentration of the specified ground substance.

15. The monitoring apparatus according to claim 14, wherein the correction unit obtains a concentration x(t) of the specified ground substance based on a following formula, and

wherein the formula is used under a premise that:

the first signal value y(t) at a certain point of time t is expressed by a linear function y(t)=ax(t)+c, where a is a calibration curve coefficient corresponding to the first biocatalyst, x is a concentration of the specified ground substance and c is a signal component based on a substance excluding the specified ground substance in a body fluid;

the second signal y′

(t) at the certain point of time t is expressed by a linear function y′

(t)=bx(t)+c, where b is a calibration curve coefficient corresponding to the second biocatalyst, x is the concentration of the specified ground substance and c is the signal component; and

a value of the signal component c in the first signal value y(t) is equal to a value of the signal component c of the second signal value y′

(t).

(Formula) x(t)=(y(t)−

y′

(t))/(a−

b)