Methods for determing cholesterol oxidase activity in an aqueous test sample, determining whether a test compound is capable of inhibiting cholesterol oxidase activity and determining the degree of cholesterol oxidase inhibitory activity

摘要

The invention provides a method for measuring the activity of cholesterol oxidase. First, a monolayer including sterol, a phospholipid and fluorescent dye labeled phospholipid is formed on a surface of a cholesterol oxidase aqueous solution. Then, it is observed whether sterol domain fade-out occurs in the monolayer. The activity of the cholesterol oxidase can be determined on the basis of both the period of time during which the sterol domain fade-out has occurred and a concentration of sterol in a cholesterol oxidase aqueous solution. This process can be applied to a method for estimating the toxicity of chemical compounds.