Multilayer analytical element for assaying fructosamine

• US 5,565,170 A
• Filed: 04/06/1995
• Issued: 10/15/1996
• Est. Priority Date: 08/30/1990
• Status: Expired due to Term

• Current Assignee: Kyoto Daiichi Kagaku Company Limited
• Original Assignee: Kyoto Daiichi Kagaku Company Limited
• Inventors: Sakamoto, Hisashi
• Primary Examiner(s): ALEXANDER, LYLE
• Application Number:
  US08/417,849
• Time in Patent Office: 558 Days
• Field of Search: 435/10, 435/25, 435/805, 436/87, 436/170, 422/56
• US Class Current: 422/422
• CPC Class Codes: G01N 33/66 involving blood sugars, e.g. galactose
• CPC Class Codes: Y10S 435/805 Test papers

Abstract

A multilayer analytical element for assaying fructosamine having a liquid-impermeable support, a dried buffer-containing layer which contains a buffer having pH of 8 to 12 formed on the support, and a tetrazolium salt-containing layer which is laminated on the buffer-containing layer, which element assays fructosamine in a short time with good accuracy.

Claims

1. A multilayer analytical element for assaying fructosamine, consisting essentially of a liquid-impermeable support, a dried buffer-containing layer which contains a buffer having a pH of 8 to 12 formed on said support, and a tetrazolium salt-containing layer which is independently prepared, dried, and laminated on said buffer-containing layer.

2. The multilayer analytical element according to claim 1, wherein said tetrazolium salt contained in said tetrazolium salt-containing layer is at least one compound selected from the group consisting of 3,3'"'"'-[3,3'"'"'-dimethoxy-(1,1'"'"'-biphenyl) -4,4'"'"'-diyl]-bis[2-(p-nitrophenyl)-5-phenyl-2H-tetrazolium chloride], 3,3'"'"'-[3,3'"'"'-dimethoxy-(1,1'"'"'-biphenyl) -4,4'"'"'-diyl]-bis[2,5-bis(p-nitrophenyl)-2H-tetrazolium chloride], 3,3'"'"'-(1,1'"'"'-biphneyl-4,4'"'"'-diyl)-bis(2,5-diphenyl-2H-tetrazolium chloride], 3-(p-iodophenyl)-2-(p-nitrophenyl)-5-phenyl-2H-tetrazolium chloride, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide and 2,5-diphenyl-3-(1-naphthyl)-2H-tetrazolium chloride.

3. The multilayer analytical element according to claim 1, wherein said buffer has a pH of 8.5 to 10.5.

4. The multilayer analytical element according to claim 1, wherein said liquid-impermeable support is a material selected from the group consisting of a plastic film, paper, and a metal foil.

5. The multilayer analytical element according to claim 1, wherein said liquid-impermeable support is a plastic film.

6. The multilayer analytical element according to claim 1, wherein said buffer is a carbonate buffer.

7. The multilayer analytical element according to claim 1, wherein said buffer-containing layer further comprises a binder.

8. The multilayer analytical element according to claim 7, wherein said binder is a hydrophilic polymer.

9. The multilayer analytical element according to claim 8, wherein said hydrophilic polymer is a member selected from the group consisting of polyvinylpyrrolidone, hydroxypropylcellulose, methylcellulose, polyacrylamide, and gelatin.

10. The multilayer analytical element according to claim 1, wherein said tetrazolium salt-containing layer is formed by impregnating a solution of said salt in a porous matrix.

11. The multilayer analytical element according to claim 10, wherein said porous matrix is a member selected from the group consisting of a filter paper, a woven fabric, a knit fabric, and a membrane filter.

12. The multilayer analytical element according to claim 1, wherein said buffer-containing layer has a wet thickness of 250 μ

m or less and said tetrazolium salt-containing layer has a thickness of 300 μ

m or less.

13. The multilayer analytical element according to claim 1, wherein said buffer-containing layer further contains uricase.

14. The multilayer analytical element according to claim 1, which is fixed on a base film using a mount or an adhesive tape.

15. The multilayer analytical element according to claim 12, wherein said buffer-containing layer has a wet thickness of about 200 μ

m, and said tetrazolium salt-containing layer has a thickness of about 250 μ

m.

16. A multilayer analytical element for assaying fructosamine, consisting essentially of a liquid-impermeable support, a dried buffer-containing layer which contains a binder, uricase, and a buffer having a pH of 8 to 12 formed on said support, and a tetrazolium salt-containing layer which is independently prepared, dried, and laminated on said buffer-containing layer.