Abstract: Provided is a method for quantifying soluble LR11 in a biological sample such as serum by an immunological means conveniently and accurately without the need of carrying out any complicated separation manipulation. An immunological quantification method for soluble LR11 in a sample derived from a mammal, including a step of treating the sample with at least one surfactant selected from a group consisting of a polyoxyalkylene alkyl ether, a polyoxyalkylene alkyl phenyl ether, an alkyl glycoside, an alkylthio glycoside, an acyl-N-methylglucamide and a salt of cholic acid.

Abstract: A method of lipid assay characterized by assaying the lipids contained in a blood component in the presence of an organic silicon compound. The method can cause specific conditions for direct methods while satisfying requirements such as no influence on precision of assay, no burden on assay apparatus, and easy availability.