Method of measuring lipid in specific lipoprotein

1. A method for assaying HDL cholesterol in a sample, comprising:

determining the specificity of an assay for HDL cholesterol, and

assaying HDL cholesterol using said assay;

wherein a mixture of a plurality of polycyclic polyoxyalkylene derivatives is employed at least in the specificity determining step, said mixture having an HLB of 14.1 to 18, and

wherein the polycyclic polyoxyalkylene derivatives are nonionic surfactants selected from the group consisting of polyoxyalkylene polycyclic phenyl ether, polyoxyethylene tribenzylphenyl ether, polyoxyalkylene polystyrylphenyl ether, polyoxyalkylene phenylphenol ether, polyoxyalkylene polystyrylphenyl ether condensate, polyoxyalkylene alkylphenyl ether condensate, polyoxyalkylene styrylated phenyl ether, and polyoxyalkylene allylphenyl ether.

2. The method of claim 1 , wherein said mixture has an HLB of 14.3 to 18.

3. The method of claim 1 , wherein said mixture is in solution form.

4. A method for assaying HDL cholesterol in a sample, comprising:

determining the specificity of an assay for HDL cholesterol, and

assaying HDL cholesterol using said assay;

wherein at least one polycyclic polyoxyalkylene derivative having an HLB of 14.1 to 18 and being selected from the group consisting of polyoxyalkylene polycyclic phenyl ether, polyoxyethylene tribenzylphenyl ether, polyoxyalkylene polystyrylphenyl ether; polyoxyalkylene phenylphenol ether, polyoxyalkylene polystyrylphenyl ether condensate, polyoxyalkylene alkylphenyl ether condensate, polyoxyalkylene styrylated phenyl ether, and polyoxyalkylene allylphenyl ether is employed at least in the specificity determining step.

5. The method of claim 4 , wherein said polycyclic polyoxyalkylene derivative has an HLB of 14.3 to 18.

6. The method in accordance with claim 4 , wherein the polycyclic polyoxyalkylene derivative is in a solution form.

7. A method for determining the amount of HDL cholesterol in a sample, comprising:

determining the specificity of an assay for HDL cholesterol by pretreating lipids other than HDL cholesterol in a biological sample to obtain a pretreated reaction mixture containing HDL cholesterol,

reacting the HDL cholesterol in said pretreated reaction mixture with an enzyme that releases cholesterol from said HDL cholesterol, and

assaying the cholesterol,

thereby determining the amount of HDL cholesterol in said biological sample;

wherein at least the determining the specificity of the assay is performed in the presence of at least one nonionic polycyclic polyoxyalkylene surfactant having an HLB of 14.1 to 18 selected from the group consisting of polyoxyalkylene polycyclic phenyl ether, polyoxyethylene tribenzylphenyl ether, polyoxyalkylene polystyrylphenyl ether, polyoxyalkylene phenylphenol ether, polyoxyalkylene polystyrylphenyl ether condensate, polyoxyalkylene alkylphenyl ether condensate, polyoxyalkylene styrylated phenyl ether, and polyoxyalkylene allylphenyl ether.

8. The method of claim 7 , wherein a mixture of a plurality of the polycyclic polyoxyalkylene surfactants is employed at least in the specificity determining step, said mixture having an HLB of 14.1 to 18.

9. The method of claim 7 , wherein said polycyclic polyoxyalkylene surfactant is in a solution form.

10. The method of claim 7 , wherein said biological sample is blood, serum or plasma.

11. The method of claim 7 , wherein said pretreated reaction mixture containing HDL cholesterol is produced without centrifugation of said biological sample.

12. The method of claim 7 , wherein said enzyme that releases cholesterol from HDL cholesterol is an esterase.

13. The method of claim 12 , wherein said esterase is employed in combination with an enzyme other than the esterase, a coenzyme, or a color coupler to assay cholesterol.

14. The method of claim 13 , wherein said HDL cholesterol is assayed by measuring the amount of change in absorbance at 37° C. at secondary wavelength 700 nm/primary wavelength 600 nm.