Lactate sensor

• US 8,999,126 B2
• Filed: 09/24/2012
• Issued: 04/07/2015
• Est. Priority Date: 09/26/2011
• Status: Active Grant

• Current Assignee: ARKRAY, Inc
• Original Assignee: ARKRAY, Inc
• Inventors: Kaneda, Hisashi, Yamaguchi, Takehiro
• Primary Examiner(s): NOGUEROLA, ALEXANDER STEPHAN
• Application Number:
  US13/625,250
• Publication Number:
  US 20130075277A1
• Time in Patent Office: 925 Days
• US Class Current: 204/403.14
• CPC Class Codes: C12Q 1/004 mediator-assisted
• CPC Class Codes: C12Q 1/005 involving specific analytes or enzymes including groups of enzymes, e.g. oxydases; C12Q1/004 takes precedence
• CPC Class Codes: C12Q 1/26 involving oxidoreductase
• CPC Class Codes: G01N 2333/904 acting on CHOH groups as donors, e.g. glucose oxidase, lactate dehydrogenase (1.1)
• CPC Class Codes: G01N 27/3272 Test elements therefor, i.e. disposable laminated substrates with electrodes, reagent and channels optical biosensors G01N33/52

Abstract

A lactate sensor capable of accurately measuring a lactate concentration in a short period of time. The lactate sensor includes an insulating substrate, an electrode system including at least a working electrode and a counter electrode provided on the substrate, and a reagent layer provided on the electrode system. The reagent layer contains lactate oxidase, it mediator, and N-(2-acetamide)-2-aminoethanesulfonic acid.

Claims

1. A lactate sensor comprising an insulating substrate, an electrode system including at least a working electrode and a counter electrode provided on the substrate, and a reagent layer provided on the electrode system,

wherein the reagent layer contains lactate oxidase, at least two mediators, and N-(2-acetamide)-2-aminoethanesulfonic acid, and

wherein one of the at least two mediators contains a ruthenium compound, and the other mediator of the at least two mediators is a phenazine methosulfate and/or a derivative thereof.

2. The lactate sensor according to claim 1, wherein the reagent layer further contains a sugar selected from the group consisting of oligosaccharides and polysaccharides.

3. The lactate sensor according to claim 2, wherein the sugar is dextran.

4. The lactate sensor according to claim 1, wherein the reagent layer further contains a layered inorganic compound and/or a surfactant.

5. The lactate sensor according to claim 1, wherein the phenazine methosulfate derivative is 1-methoxy-5-methyl phenazinium methyl sulfate.

6. A lactate concentration measurement system for measuring a lactate concentration in a sample, the system comprising:

the lactate sensor of claim 1,

a means for applying voltage to the electrode system of the lactate sensor, and

a means for measuring a current in the electrode system.

7. A method for measuring a lactate concentration, comprising:

bringing a sample into contact with a reagent layer containing lactate oxidase and N-(2-acetamide)-2-aminoethanesulfonic acid, and

electrochemically measuring a reaction between lactate in the sample and the lactate oxidase via at least two mediators, and

wherein one of the at least two mediators contains a ruthenium compound, and the other mediator of the at least two mediators is a phenazine methosulfate and/or a derivative thereof.

8. The measurement method according to claim 7, carried out using the lactate sensor,

wherein the lactate sensor comprises an insulating substrate, an electrode system including at least a working electrode and a counter electrode provided on the substrate, and a reagent layer provided on the electrode system,

wherein the reagent layer contains lactate oxidase, at least two mediators, and N-(2-acetamide)-2-aminoethanesulfonic acid.

9. The measurement method according to claim 8, comprising:

applying voltage to the electrode system after the contact,

measuring a value of a response current discharged when the voltage is applied, and

calculating a lactate concentration in the sample based on the value of a response current.

10. A method for producing a lactate sensor, the method comprising forming a reagent layer containing lactate oxidase, at least two mediators, and N-(2-acetamide)-2-aminoethanesulfonic acid on an electrode system provided on an insulating substrate, the electrode system including at least a working electrode and a counter electrode, and

wherein one of the at least two mediators contains a ruthenium compound, and one other mediator of the at least two mediators is a phenazine methosulfate and/or a derivative thereof.