Colorimetric determination of total, free and ester cholesterol in tissue extracts

Abstract

A method is described for detn. of total, free and ester cholesterol in tissue extracts by precipitation with digitonin in acidified medium at room temp. The digi-tonide is separated by centrifuging and then decomposed by boiling with benzene. The digitonin, thus freed, is precipitated by light petroleum and is centrifuged off; the cholesterol remains dissolved in the light petroleum which is decanted and evaporated. The color, developed by the Liebermann-Burchard reaction on cholesterol samples obtained in this way, is indistinguishable from that of the standard when compared in a colorimeter.