Abstract: To provide a method for simply and precisely measuring cholesterol (LDL-C) in low-density lipoprotein in a sample without use of any surfactant having an alkylphenol structure, in terms of environmental friendliness. A method for measuring LDL-C in a sample, the method comprising: reacting the sample with (i) a combination of cholesterol ester hydrolase and cholesterol oxidase or (ii) a combination of cholesterol ester hydrolase, an oxidized coenzyme and cholesterol dehydrogenase, in an aqueous solvent which comprises: [a] one or more surfactants selected from the group consisting of a polyoxyethylene alkyl ether and a polyoxyethylene polyoxypropylene alkyl ether; and [b] a polyoxyethylene polyoxypropylene copolymer; and which does not comprise any surfactant having an alkylphenol structure; and measuring a substance formed or consumed in the reaction.

Abstract: The present invention provides a method for stabilizing a cholesterol oxidase, a method for preserving a cholesterol oxidase, and a stabilized composition of cholesterol oxidase. A method for stabilizing a cholesterol oxidase and a method for preserving a cholesterol oxidase which comprises allowing the cholesterol oxidase to coexist with an ?-keto acid in an aqueous medium, and, a stabilized composition of cholesterol oxidase which comprises the cholesterol oxidase being allowed to coexist with an ?-keto acid in an aqueous medium. The method for stabilizing a cholesterol oxidase, the method for preserving a cholesterol oxidase, and a stabilized composition of cholesterol oxidase according to the present invention are useful for clinical diagnosis such as metabolic syndrome.

Abstract: Provided is a measuring method of a component to be measured in a specimen while suppressing an influence of bilirubin. A measuring method of a component to be measured, comprising converting the component to be measured in the specimen to hydrogen peroxide through an enzymatic reaction, reacting the formed hydrogen peroxide with an oxidative-coloring chromogen in the presence of a peroxidase, and measuring an absorbance of the colored reaction solution to thereby determine the component to be measured, wherein a fatty acid or a salt thereof coexists. The measuring method of a component to be measured in a specimen according to the present invention is useful in clinical diagnosis.

Abstract: Provided are: a method for stabilizing an ascorbic acid oxidase; a method for preserving an ascorbic acid oxidase; and a stabilized composition of an ascorbic acid oxidase. A method for stabilizing an ascorbic acid oxidase and a method for preserving an ascorbic acid oxidase, each of the methods comprising allowing an ascorbic acid oxidase to coexist with nitrous acid or a salt thereof, or a nitrous acid ester in an aqueous medium; and a stabilized composition of an ascorbic acid oxidase, which comprises an ascorbic acid oxidase being allowed to coexist with nitrous acid or a salt thereof, or a nitrous acid ester in an aqueous medium. The method for stabilizing an ascorbic acid oxidase, the method for preserving an ascorbic acid oxidase, and the stabilized composition of an ascorbic acid oxidase according to the present invention are useful for clinical diagnosis and the like.

Abstract: Provided are: a method for stabilizing an ascorbic acid oxidase; a method for preserving an ascorbic acid oxidase; and a stabilized composition of an ascorbic acid oxidase. A method for stabilizing an ascorbic acid oxidase and a method for preserving an ascorbic acid oxidase, each of the methods comprising allowing an ascorbic acid oxidase to coexist with nitrous acid or a salt thereof, or a nitrous acid ester in an aqueous medium; and a stabilized composition of an ascorbic acid oxidase, which comprises an ascorbic acid oxidase being allowed to coexist with nitrous acid or a salt thereof, or a nitrous acid ester in an aqueous medium. The method for stabilizing an ascorbic acid oxidase, the method for preserving an ascorbic acid oxidase, and the stabilized composition of an ascorbic acid oxidase according to the present invention are useful for clinical diagnosis and the like.

Abstract: The present invention provides a method for stabilizing a cholesterol oxidase, a method for preserving a cholesterol oxidase, and a stabilized composition of cholesterol oxidase. A method for stabilizing a cholesterol oxidase and a method for preserving a cholesterol oxidase which comprises allowing the cholesterol oxidase to coexist with an ?-keto acid in an aqueous medium, and, a stabilized composition of cholesterol oxidase which comprises the cholesterol oxidase being allowed to coexist with an ?-keto acid in an aqueous medium. The method for stabilizing a cholesterol oxidase, the method for preserving a cholesterol oxidase, and a stabilized composition of cholesterol oxidase according to the present invention are useful for clinical diagnosis such as metabolic syndrome.

Abstract: Provided is a measuring method of a component to be measured in a specimen while suppressing an influence of bilirubin. A measuring method of a component to be measured, comprising converting the component to be measured in the specimen to hydrogen peroxide through an enzymatic reaction, reacting the formed hydrogen peroxide with an oxidative-coloring chromogen in the presence of a peroxidase, and measuring an absorbance of the colored reaction solution to thereby determine the component to be measured, wherein a fatty acid or a salt thereof coexists. The measuring method of a component to be measured in a specimen according to the present invention is useful in clinical diagnosis.