METHOD FOR MEASURING GLYCATED HEMOGLOBIN

• US 20130115646A1
• Filed: 08/09/2011
• Published: 05/09/2013
• Est. Priority Date: 08/11/2010
• Status: Active Grant

• Current Assignee: Kyowa Medex Co., Ltd. (Resonac Holdings Corp.)
• Original Assignee: Kyowa Medex Co., Ltd. (Resonac Holdings Corp.)
• Inventors: Murakami, Tomomi, Tsunoda, Haruki, Yoda, Ayako, Soya, Haruyo, Ohsugi, Yu, Matsushita, Masashi
• Granted Patent: US 9,090,931 B2
• Time in Patent Office: Days
• US Class Current: 435/23
• CPC Class Codes: C12Q 1/26 involving oxidoreductase
• CPC Class Codes: C12Q 1/28 involving peroxidase
• CPC Class Codes: C12Q 1/37 involving peptidase or proteinase
• CPC Class Codes: C12Q 1/54 involving glucose or galactose
• CPC Class Codes: G01N 21/78 producing a change of colour
• CPC Class Codes: G01N 33/723 Glycosylated haemoglobin

Abstract

It is to provide a method for measuring glycated hemoglobin in a hemoglobin-containing sample, comprising: reacting glycated hemoglobin in the hemoglobin-containing sample with a proteolytic enzyme in the presence of at least one salt selected from the group consisting of a pyridinium salt, a phosphonium salt, an imidazolium salt, and an isoquinolinium salt; reacting the obtained reaction product with fructosyl peptide oxidase; and measuring the generated hydrogen peroxide. The present invention provides a method for accurately measuring glycated hemoglobin in a hemoglobin-containing sample.

Claims

1. A method for measuring glycated hemoglobin in a hemoglobin-containing sample, comprising:

reacting glycated hemoglobin in the hemoglobin-containing sample with a proteolytic enzyme in the presence of at least one salt selected from the group consisting of a pyridinium salt represented by the following formula (I), a phosphonium salt represented by the following formula (II), an imidazolium salt represented by the following formula (III), and an isoquinolinium salt represented by the following formula (IV);

reacting the obtained reaction product with fructosyl peptide oxidase; and

measuring the generated hydrogen peroxide;

2. The method according to claim 1, wherein the measurement of the hydrogen peroxide is performed using a hydrogen peroxide measuring reagent.

3. The method according to claim 2, wherein the hydrogen peroxide measuring reagent is a reagent comprising peroxidase and a leuco chromogen.

4. The method according to claim 3, wherein the leuco chromogen is a phenothiazine chromogen.

5. The method according to claim 4, wherein the phenothiazine chromogen is 10-(carboxymethylaminocarbonyl)-3,7-bis(dimethylamino)phenothiazine.

6. A reagent for measuring glycated hemoglobin in a hemoglobin-containing sample, comprising a proteolytic enzyme, fructosyl peptide oxidase, and at least one salt selected from the group consisting of a pyridinium salt represented by the following formula (I), a phosphonium salt represented by the following formula (II), an imidazolium salt represented by the following formula (III), and an isoquinolinium salt represented by the following formula (IV):

7. The reagent according to claim 6, further comprising a hydrogen peroxide measuring reagent.

8. The reagent according to claim 7, wherein the hydrogen peroxide measuring reagent is a reagent comprising peroxidase and a leuco chromogen.

9. The reagent according to claim 8, wherein the leuco chromogen is a phenothiazine chromogen.

10. The reagent according to claim 9, wherein the phenothiazine chromogen is 10-(carboxymethylaminocarbonyl)-3,7-bis(dimethylamino)phenothiazine.

11. A kit for measuring glycated hemoglobin in a hemoglobin-containing sample comprising:

a first reagent comprising a proteolytic enzyme and at least one salt selected from the group consisting of a pyridinium salt represented by the following formula (I), a phosphonium salt represented by the following formula (II), an imidazolium salt represented by the following formula (III), and an isoquinolinium salt represented by the following formula (IV); and

a second reagent comprising fructosyl peptide oxidase;

12. The kit according to claim 11, wherein the first reagent and the second reagent or the second reagent and the first reagent further comprise peroxidase and a leuco chromogen, respectively.

13. The kit according to claim 12, wherein the leuco chromogen is a phenothiazine chromogen.

14. The kit according to claim 13, wherein the phenothiazine chromogen is 10-(carboxymethylaminocarbonyl)-3,7-bis(dimethylamino)phenothiazine.

15. A method for preserving an aqueous solution containing a leuco chromogen, comprising adding at least one salt selected from the group consisting of a pyridinium salt represented by the following formula (I), a phosphonium salt represented by the following formula (II), an imidazolium salt represented by the following formula (III), and an isoquinolinium salt represented by the following formula (IV) to the aqueous solution containing a leuco chromogen:

17. The method according to claim 15, wherein the leuco chromogen is a phenothiazine chromogen.

18. The method according to claim 17, wherein the phenothiazine chromogen is 10-(carboxymethylaminocarbonyl)-3,7-bis(dimethylamino)phenothiazine.

16. A method for stabilizing a leuco chromogen, comprising allowing the leuco chromogen to coexist in an aqueous solution comprising at least one salt selected from the group consisting of a pyridinium salt represented by the following formula (I), a phosphonium salt represented by the following formula (II), an imidazolium salt represented by the following formula (III), and an isoquinolinium salt represented by the following formula (IV):

19. The method according to claim 16, wherein the leuco chromogen is a phenothiazine chromogen.

20. The method according to claim 19, wherein the phenothiazine chromogen is 10-(carboxymethylaminocarbonyl)-3,7-bis(dimethylamino)phenothiazine.