Method for measuring cholesterol in high-density lipoprotein
Provided is a method for measuring cholesterol in high-density lipoprotein (HDL) simply and accurately. A method for measuring cholesterol in high-density lipoprotein in a specimen, comprising reacting the specimen with i) a cholesterol ester hydrolase and a cholesterol oxidase, or ii) a cholesterol ester hydrolase, an oxidized coenzyme, and a cholesterol dehydrogenase, in an aqueous medium comprising at least one substance selected from the group consisting of pyridinium salts and quaternary ammonium salts each having a specific structure, and a polyanion to form hydrogen peroxide or reduced coenzyme and measuring the formed hydrogen peroxide or reduced coenzyme.
1. A method for measuring cholesterol in high-density lipoprotein in a specimen, comprising
(1) reacting the specimen with i) a cholesterol ester hydrolase and a cholesterol oxidase, or ii) a cholesterol ester hydrolase, an oxidized coenzyme, and a cholesterol dehydrogenase, in an aqueous medium comprising a polyanion, and at least one substance selected from the group consisting of a substance represented by formula (I):
wherein R 1 represents a substituted or unsubstituted alkyl or alkenyl having 8 to 14 carbon atoms; R a represents a hydrogen atom, a substituted or unsubstituted alkyl, or a substituted or unsubstituted alkenyl; n represents an integer of 1 to 5; and X − represents a monovalent anion, and a substance represented by formula (II):
wherein R 2 represents a substituted or unsubstituted alkyl or alkenyl having 6 to 30 carbon atoms; R 3 represents a substituted or unsubstituted alkyl having 1 to 6 carbon atoms or alkenyl having 2 to 6 carbon atoms; R 4 represents a hydrogen atom, substituted or unsubstituted aryl, or substituted or unsubstituted alkyl; and Y − represents a monovalent anion, to form hydrogen peroxide or a reduced coenzyme;
(2) measuring the formed hydrogen peroxide or reduced coenzyme; and
(3) calculating the concentration of HDL cholesterol in the specimen from the value measured in (2) and a previously-prepared calibration curve showing the relationship between HDL cholesterol concentrations and measured values of hydrogen peroxide or reduced coenzyme.
2. The method according to claim 1 , wherein the aqueous medium further comprises albumin.
3. The method according to claim 2 , wherein the polyanion is dextran sulfate or a salt thereof.
4. The method according to claim 1 , wherein the polyanion is dextran sulfate or a salt thereof.
5. A reagent for measuring cholesterol in high-density lipoprotein, comprising a polyanion, a cholesterol ester hydrolase, a cholesterol oxidase, a reagent for measuring hydrogen peroxide, and at least one substance selected from the group consisting of a substance represented by formula (I):
wherein R 1 represents a substituted or unsubstituted alkyl or alkenyl having 8 to 14 carbon atoms; R a represents a hydrogen atom, a substituted or unsubstituted alkyl, or a substituted or unsubstituted alkenyl; n represents an integer of 1 to 5; and X − represents a monovalent anion, and a substance represented by formula (II):
wherein R 2 represents a substituted or unsubstituted alkyl or alkenyl having 6 to 30 carbon atoms; R 3 represents a substituted or unsubstituted alkyl having 1 to 6 carbon atoms or alkenyl having 2 to 6 carbon atoms; R 4 represents a hydrogen atom, a substituted or unsubstituted aryl, or a substituted or unsubstituted alkyl; and Y − represents a monovalent anion.
6. The reagent according to claim 5 , further comprising albumin.
7. The reagent according to claim 6 , wherein the polyanion is dextran sulfate or a salt thereof.
8. The reagent according to claim 5 , wherein the polyanion is dextran sulfate or a salt thereof.
9. A reagent for measuring cholesterol in high-density lipoprotein, comprising a polyanion, a cholesterol ester hydrolase, a cholesterol dehydrogenase, an oxidized coenzyme, and at least one substance selected from the group consisting of a substance represented by formula (I):
wherein R 1 represents a substituted or unsubstituted alkyl or alkenyl having 8 to 14 carbon atoms; R a represents a hydrogen atom, a substituted or unsubstituted alkyl, or a substituted or unsubstituted alkenyl; n represents an integer of 1 to 5; and X − represents a monovalent anion, and a substance represented by formula (II):
wherein R 2 represents a substituted or unsubstituted alkyl or alkenyl having 6 to 30 carbon atoms; R 3 represents a substituted or unsubstituted alkyl having 1 to 6 carbon atoms or alkenyl having 2 to 6 carbon atoms; R 4 represents a hydrogen atom, a substituted or unsubstituted aryl, or a substituted or unsubstituted alkyl; and Y − represents a monovalent anion.
10. The reagent according to claim 9 , further comprising a reagent for measuring a reduced coenzyme.
11. The reagent according to claim 9 , further comprising albumin.
12. The reagent according to claim 11 , wherein the polyanion is dextran sulfate or a salt thereof.
13. The reagent according to claim 9 , wherein the polyanion is dextran sulfate or a salt thereof.
14. The reagent according to claim 10 , further comprising albumin.
15. The reagent according to claim 14 , wherein the polyanion is dextran sulfate or a salt thereof.
16. The reagent according to claim 10 , wherein the polyanion is dextran sulfate or a salt thereof.
17. A kit for measuring cholesterol in high-density lipoprotein comprising a first reagent and a second reagent, wherein a polyanion, and at least one substance selected from the group consisting of a substance represented by formula (I):
wherein R 1 represents a substituted or unsubstituted alkyl or alkenyl having 8 to 14 carbon atoms; R a represents a hydrogen atom, a substituted or unsubstituted alkyl, or a substituted or unsubstituted alkenyl; n represents an integer of 1 to 5; and X − represents a monovalent anion, and a substance represented by formula (II):
wherein R 2 represents a substituted or unsubstituted alkyl or alkenyl having 6 to 30 carbon atoms; R 3 represents a substituted or unsubstituted alkyl having 1 to 6 carbon atoms or alkenyl having 2 to 6 carbon atoms; R 4 represents a hydrogen atom, a substituted or unsubstituted aryl, or a substituted or unsubstituted alkyl; and Y − represents a monovalent anion are comprised in the first reagent, a cholesterol oxidase is comprised in the second reagent, a reagent for measuring hydrogen peroxide is comprised in either the first or second reagent, or in both of the first and second reagents, and a cholesterol ester hydrolase is comprised in either the first or second reagent, or in both of the first and second reagents.
18. The kit according to claim 17 , further comprising albumin in either the first or second reagent, or in both of the first and second reagents.
19. The kit according to claim 17 , wherein the polyanion is dextran sulfate or a salt thereof.
20. The kit according to claim 18 , wherein the polyanion is dextran sulfate or a salt thereof.
21. A kit for measuring cholesterol in high-density lipoprotein comprising a first reagent and a second reagent, wherein a polyanion, and at least one substance selected from the group consisting of a substance represented by formula (I):
wherein R 1 represents a substituted or unsubstituted alkyl or alkenyl having 8 to 14 carbon atoms; R a represents a hydrogen atom, a substituted or unsubstituted alkyl, or a substituted or unsubstituted alkenyl; n represents an integer of 1 to 5; and X − represents a monovalent anion, and a substance represented by formula (II):
wherein R 2 represents a substituted or unsubstituted alkyl or alkenyl having 6 to 30 carbon atoms; R 3 represents a substituted or unsubstituted alkyl having 1 to 6 carbon atoms or alkenyl having 2 to 6 carbon atoms; R 4 represents a hydrogen atom, a substituted or unsubstituted aryl, or a substituted or unsubstituted alkyl; and Y − represents a monovalent anion are comprised in the first reagent, a cholesterol dehydrogenase is comprised in the second reagent, an oxidized coenzyme is comprised in either the first or second reagent, or in both of the first and second reagents, and a cholesterol ester hydrolase is comprised in either the first or second reagent, or in both of the first and second reagents.
22. The kit according to claim 21 , further comprising a reagent for measuring a reduced coenzyme in either the first or second reagent, or in both of the first and second reagents.
23. The kit according to claim 21 , further comprising albumin in either the first or second reagent, or in both of the first and second reagents.
24. The kit according to claim 23 , wherein the polyanion is dextran sulfate or a salt thereof.
25. The kit according to claim 22 , further comprising albumin in either the first or second reagent, or in both of the first and second reagents.
26. The kit according to claim 25 , wherein the polyanion is dextran sulfate or a salt thereof.
27. The kit according to claim 21 , wherein the polyanion is dextran sulfate or a salt thereof.
28. The kit according to claim 22 , wherein the polyanion is dextran sulfate or a salt thereof.