DETERMINATION OF HYDROGEN PEROXIDE CONCENTRATIONS

• US 20100258451A1
• Filed: 09/18/2007
• Published: 10/14/2010
• Est. Priority Date: 09/18/2006
• Status: Active Grant

• Current Assignee: Alexander Adlassnig
• Original Assignee: Alexander Adlassnig
• Inventors: Adlassnig, Alexander
• Granted Patent: US 9,938,555 B2
• Time in Patent Office: Days
• US Class Current: 205/777.500
• CPC Class Codes: C12Q 1/006 for glucose
• CPC Class Codes: G01N 27/3273 Devices therefor, e.g. test element readers, circuitry details not specific to biochemical electrodes G01N33/4875

Abstract

For amperometric determination of the hydrogen peroxide concentration in a fluid sample, different electrical voltage steps are applied to the electrodes. In this process, at least one voltage is suitable for measuring the hydrogen peroxide concentration in the fluid sample, and at least one additional voltage is suitable for measuring the concentration of a substance in the fluid sample that acts as an interfering substance during measurement of the hydrogen peroxide concentration.

Claims

1. Method for determining the glucose concentration in a fluid sample, in which the fluid sample is brought into contact with glucose oxidase and the amount of the hydrogen peroxide forming thereby is amperometrically measured with the aid of electrodes, to which different voltage steps are applied,

characterized in that the method is comprised of the following steps:

applying an activation voltage for lowering the voltage for the measurement of the hydrogen peroxide concentration;

measurement at a voltage that is suitable for measuring the hydrogen peroxide concentration in the fluid sample and which was lowered by previously applying the activation voltage;

measurement at least one voltage that is suitable for measuring the concentration of a substance in the fluid sample that acts as an interfering substance during measurement of the hydrogen peroxide concentration; and

estimating, with the aid of the result of the measurement at the voltage that is suitable for measuring the concentration of the interfering substance, the influence of this interfering substance on the result of the measurement at the voltage that is suitable for measuring the hydrogen peroxide concentration in the fluid sample.

2. Method according to claim 1, characterized in that, at the voltage suitable for measuring the hydrogen peroxide concentration in the fluid sample, the current flowing between the electrodes changes at most exponentially with the hydrogen peroxide concentration.

3. Method according to claim 2, characterized in that, at the voltage suitable for measuring the hydrogen peroxide concentration in the fluid sample, the current flowing between the electrodes changes essentially linearly with the hydrogen peroxide concentration.

4. Method according to claim 3, characterized in that, at a voltage suitable for measuring the concentration of an interfering substance in the fluid sample, the current flowing between the electrodes changes at most exponentially with the interfering substance concentration.

5. Method according to claim 4, characterized in that, at a voltage suitable for measuring the concentration of an interfering substance in the fluid sample, the current flowing between the electrodes changes essentially linearly with the interfering substance concentration.

7. Method according to claim 1, characterized in that, in order to estimate the influence of the interfering substances, the result of the measurement at voltages suitable for measuring the hydrogen peroxide concentration is corrected with the results of the measurements at the voltages suitable for measuring the interfering substances, each multiplied by a weighting factor empirically determined in advance.

8. Method according to claim 7, characterized in that the measurement result is a current value.

9. Method according to claim 1, characterized in that the measurements at the different voltages are carried out multiple times.

11. Method according to claim 1, characterized in that the activation voltage lies between −

200 and +700 mV.

12. Method according to claim 11, characterized in that the activation voltage is 0 V.

13. Method according to claim 1, characterized in that a maximum of 10 different voltages are applied.

14. Method according to claim 13, characterized in that precisely four different voltages are applied.

15. Method according to claim 14, characterized in that the four voltages lie in the ranges from −

1200 to −

800 mV, −

600 to 0 mV, −

200 to +700 mV and +200 to +1400 mV.

16. Method according to claim 1, characterized in that the fluid sample is blood, sweat, urine, or milk.

17. Method according to claim 1, characterized in that the interfering substances are urea, amino acids, ascorbic acid, or medications.

18. Method according to claim 1, characterized in that the hydrogen peroxide is the end product of an enzyme reaction.

19. Method according to claim 18, characterized in that at least one oxoreductase is used in the enzyme reaction.

20. Method according to claim 18, characterized in that the oxoreductase that is used is glucose oxidase, lactate oxidase, cholesterol oxidase, alcohol dehydrogenase, xanthine oxidase, amino acid oxidase, ascorbic acid oxidase, acyl-CoA oxidase, uricase, glutamate dehydrogenase, or fructose dehydrogenase.

21. Method according to claim 1, characterized in that the electrodes are gold electrodes.

22. Measurement device that has two or more electrodes, characterized in that it is set up to carry out the method according to claim 1.

23. Measurement device that can be connected to a measurement strip which has two or more electrodes, characterized in that it is set up to carry out the method according to claim 1 after connection to the measurement strip.

24. Measurement device according to claim 22, characterized in that the electrochemical voltage drops in the fluid sample are compensated through a control circuit.

25. Measurement device according to claim 22, characterized in that the voltage of the measurement electrode is held at a constant value during the entire measurement by a control circuit.

6. (canceled)

10. (canceled)