EQUILIBRIUM POTENTIAL ESTIMATING METHOD, EQUILIBRIUM POTENTIAL ESTIMATING DEVICE, CONCENTRATION ESTIMATING DEVICE, PROGRAM, MEDIUM AND BLOOD SUGAR ESTIMATING DEVICE

• US 20170248545A1
• Filed: 05/12/2017
• Published: 08/31/2017
• Est. Priority Date: 11/12/2014
• Status: Active Grant

• Current Assignee: Asahi Kasei Kabushiki Kaisha
• Original Assignee: Asahi Kasei Kabushiki Kaisha
• Inventors: AYABE, Masaaki, UDAGAWA, Ken
• Granted Patent: US 10,641,730 B2
• Time in Patent Office: Days
• CPC Class Codes: C02F 2201/46135 Voltage
• CPC Class Codes: C02F 2201/4614 Current
• CPC Class Codes: C02F 2209/04 Oxidation reduction potential [ORP]
• 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 27/3274 Corrective measures, e.g. error detection, compensation for temperature or hematocrit, calibration coding of calibration information G01N33/48771
• CPC Class Codes: G01N 27/4168 Oxidation-reduction potential, e.g. for chlorination of water water analysis G01N33/18

Abstract

An oxidation-reduction substance equilibrium potential estimating method is provided, the method including:

• • applying a voltage to an electrode contacting a sample containing an oxidation-reduction substance and sweeping the voltage;
  • measuring a current flowing through the electrode;
  • if an integrated value of the current becomes a value within a reference range, determining whether to sweep the voltage in an opposite direction to a sweep direction in the previous sweeping or to terminate sweeping of the voltage;
  • if it is determined to terminate sweeping of the voltage, estimating an oxidation-reduction substance equilibrium potential at a value of the voltage; and
  • if it is determined to sweep the voltage, sweeping the voltage in an opposite direction to a sweep direction in the previous sweeping.

Claims

1. An oxidation-reduction substance equilibrium potential estimating method, comprising:

applying a voltage to an electrode contacting a sample containing an oxidation-reduction substance and sweeping the voltage;

measuring a current flowing through the electrode;

if an integrated value of the current becomes a value within a reference range, determining whether to sweep the voltage in an opposite direction to a sweep direction in the previous sweeping or to terminate sweeping of the voltage;

if it is determined to terminate sweeping of the voltage, estimating an oxidation-reduction substance equilibrium potential at a value of the voltage; and

if it is determined to sweep the voltage, sweeping the voltage in an opposite direction to a sweep direction in the previous sweeping.

2. The oxidation-reduction substance equilibrium potential estimating method according to claim 1, wherein

if an integrated value of the current becomes a value within the reference range, the determining has judging whether or not a sweep width of the voltage, a change amount between the currents corresponding to the sweep width or a change amount between the integrated values corresponding to the sweep width is within a tolerated range,

if it is judged that the value is within the tolerated range, the estimating has estimating the equilibrium potential at a voltage value within the tolerated range, and

if it is judged that the value is outside the tolerated range, the sweeping the voltage in an opposite direction has sweeping the voltage in an opposite direction to a sweep direction in the previous sweeping.

3. The oxidation-reduction substance equilibrium potential estimating method according to claim 1, wherein

the determining has:

determining to sweep the voltage in an opposite direction to a sweep direction in the previous sweeping if a number of times of the sweeping is less than N (N is a natural number. The same applies hereinafter.); and

determining to terminate sweeping of the voltage if the number of times of the sweeping is N,

if the number of times of the sweeping is N, the estimating has estimating the equilibrium potential at a value of the voltage, and

if the number of times of the sweeping is less than N, the sweeping the voltage in an opposite direction has sweeping the voltage in an opposite direction to a sweep direction in the previous sweeping.

4. The oxidation-reduction substance equilibrium potential estimating method according to claim 2, wherein the determining and the sweeping the voltage in an opposite direction are repeatedly executed until it is judged that the sweep width of the voltage, a change amount between the currents corresponding to the sweep width or a change amount between the integrated values corresponding to the sweep width is within the tolerated range.

5. The oxidation-reduction substance equilibrium potential estimating method according to claim 1, wherein a sweep speed for the voltage is adjusted such that time during which the voltage is being swept becomes constant since the integrated value of the current becomes a value within the reference range until the integrated value of the current next becomes a value within the reference range.

6. The oxidation-reduction substance equilibrium potential estimating method according to claim 1, wherein the sweeping the voltage in an opposite direction has sweeping the voltage at a sweep speed lower than a sweep speed in the previous sweeping.

7. The oxidation-reduction substance equilibrium potential estimating method according to claim 6, wherein the sweep speed at the sweeping the voltage in an opposite direction is 0.1 to 0.8 times a sweep speed in the previous sweeping.

8. The oxidation-reduction substance equilibrium potential estimating method according to claim 7, wherein the sweep speed at the sweeping the voltage in an opposite direction is 0.2. to 0.7 times a sweep speed in the previous sweeping.

9. The oxidation-reduction substance equilibrium potential estimating method according to claim 8, wherein the sweep speed at the sweeping the voltage in an opposite direction is 0.4 to 0.6 times a sweep speed in the previous sweeping.

10. The oxidation-reduction substance equilibrium potential estimating method according to claim 2, wherein the determining has determining whether to terminate sweeping of the voltage if a symbol of the integrated value is reversed.

11. An oxidation-reduction substance concentration estimating method comprising:

the applying and sweeping to the sweeping the voltage in an opposite direction in the oxidation-reduction substance equilibrium potential estimating method according to claim 2; and

estimating a concentration of the oxidation-reduction substance based on the voltage value.

12. An oxidation-reduction substance equilibrium potential estimating device comprising:

a voltage applying unit that applies a voltage to an electrode contacting a sample containing an oxidation-reduction substance;

a current measuring unit that measures a current flowing through the electrode; and

a signal processing unit that instructs the voltage applying unit to sweep the voltage and, if an integrated value of the current becomes a value within a reference range, determines whether to sweep the voltage in an opposite direction to a sweep direction in the previous sweeping or to terminate sweeping of the voltage, wherein

the signal processing unit instructs the voltage applying unit to;

estimate an oxidation-reduction substance equilibrium potential at a value of the voltage if it is determined to terminate sweeping of the voltage; and

sweep the voltage in an opposite direction to a previous sweep direction if it is determined to sweep the voltage.

13. The oxidation-reduction substance equilibrium potential estimating device according to claim 12, wherein the signal processing unit:

judges whether or not a sweep width of the voltage, a change amount between the currents corresponding to the sweep width or a change amount between the integrated values corresponding to the sweep width is within a tolerated range if an integrated value of the current becomes a value within the reference range; and

estimates the equilibrium potential at a voltage value within the tolerated range if it is judged that the value is within the tolerated range, and sweeps the voltage in an opposite direction to a sweep direction in the previous sweeping if it is judged that the value is outside the tolerated range.

14. The oxidation-reduction substance equilibrium potential estimating device according to claim 12, wherein the signal processing unit:

sweeps the voltage in an opposite direction to a sweep direction in the previous sweeping if a number of times of the sweeping is less than N (N is a natural number. The same applies hereinafter.); and

terminates sweeping of the voltage and estimates the equilibrium potential at a value of the voltage if the number of times of the sweeping is N.

15. The oxidation-reduction substance equilibrium potential estimating device according to claim 13, wherein the signal processing unit repeats instructing the voltage applying unit to sweep the voltage in an opposite direction to a previous sweep direction until the sweep width of the voltage, a change amount between the currents corresponding to the sweep width or a change amount between the integrated values corresponding to the sweep width becomes a value within the tolerated range.

16. The oxidation-reduction substance equilibrium potential estimating device according to claim 13, wherein the signal processing unit adjusts a sweep speed for the voltage such that time during which the voltage is being swept becomes constant since the integrated value of the current becomes a value within the reference range until the integrated value of the current next becomes a value within the reference range.

17. The oxidation-reduction substance equilibrium potential estimating device according to claim 13, wherein the signal processing unit instructs the voltage applying unit to sweep the voltage at a sweep speed lower than a previous sweep speed if the sweep width of the voltage is not within the tolerated range.

18. The oxidation-reduction substance equilibrium potential estimating device according to claim 17, wherein the signal processing unit instructs the voltage applying unit to sweep the voltage at a rate which is 0.1 to 0.8 times a previous sweep speed if the sweep width of the voltage is not within the tolerated range.

19. The oxidation-reduction substance equilibrium potential estimating device according to claim 18, wherein the signal processing unit instructs the voltage applying unit to sweep the voltage at a rate which is 0.2 to 0.7 times a previous sweep speed if the sweep width of the voltage is not within the tolerated range.

20. The oxidation-reduction substance equilibrium potential estimating device according to claim 19, wherein the signal processing unit instructs the voltage applying unit to sweep the voltage at a rate which is 0.4 to 0.6 times a previous sweep speed if the sweep width of the voltage is not within the tolerated range.

21. The oxidation-reduction substance equilibrium potential estimating device according to claim 12, wherein the signal processing unit determines whether to terminate sweeping of the voltage if a symbol of the integrated value is reversed.

22. An oxidation-reduction substance concentration estimating device comprising:

the oxidation-reduction substance equilibrium potential estimating device according to claim 12; and

an estimating unit that estimates a concentration of the oxidation-reduction substance based on a value of the voltage.

23. A blood sugar estimating device comprising:

the oxidation-reduction substance concentration estimating device according to claim 22; and

the electrode.