Patent ID: 8158375
Filing Date: 2012-04-17
Classification: C08F,G01N

Abstract:
1. A determination method of cholesterol in lipoprotein or lipoproteins (method (A)), which measures an amount of cholesterol in the lipoproteins other than a specific lipoprotein(s) in a biological sample and comprises: (a) contacting the biological sample in the presence of a polymer containing monomer units as constituents with a reagent group (1) comprising cholesterol esterase and cholesterol oxidase or a reagent group (2) comprising cholesterol esterase, cholesterol dehydrogenase, and NAD(P); (b) measuring absorbance at least at a time after substantial completion of a reaction of cholesterol in lipoproteins other than the specific lipoprotein(s) in the biological sample in the presence of the polymer and before substantial initiation of a reaction of the cholesterol in the specific lipoprotein(s) in the biological sample with the reagent (1) or (2) in the presence of the polymer; and (c) calculating the amount of cholesterol in the lipoproteins other than the specific lipoprotein(s) in the biological sample based on a value of the absorbance, wherein the monomer units as the constituents of the polymer comprise: a polyethylene glycol segment as the monomer unit represented by formula (1) (hereinafter abbreviated as PEG-Seg): wherein, k represents an integer of 10 to 250; a monomer unit represented by formula (2) (MU-A): wherein, R 1 represents a hydrogen atom or C 1 -C 3 alkyl group; and a monomer unit represented by formula (3) (MU-B); wherein, R 2 represents a hydrogen atom or C 1 -C 3 alkyl group, and R 3 represents a group of formula (4): wherein, R 4 represents an alkyl group, a haloalkyl group, a bornanyl group, an alkoxy group, an aralkyl group, or an alkylcarbamoyl group, wherein the specific lipoprotein is high density lipoprotein (HDL), low density lipoprotein (LDL), or a combination of HDL and LDL, wherein a) when the specific lipoprotein is HDL, a composition ratio by weight of an amount of the MU-A relative to an amount of the MU-B and a composition ratio by weight of a total amount of the MU-A and MU-B relative to an amount of the PEG-Seg in the polymer are: b) when the specific lipoprotein is LDL, the composition ratios in the polymer are: c) when the specific lipoproteins are a combination of HDL and LDL, the composition ratios in the polymer are: wherein the determination method does not include a step of separation or a step of isolation of the lipoprotein or the lipoproteins containing the cholesterol for which the amount is measured.