A REVISION OF THE SCHOENHEIMER-SPERRY METHOD FOR CHOLESTEROL DETERMINATION

Abstract

A study of the precipitation of cholesterol by digitonin under various conditions within the framework of a revised Schoenheimer-Sperry method gave the following results: Precipitation for 16 to 18 hrs. at room temp. with solns. of digitonin in approx. 50% alcohol, or with freshly prepared aqueous solns., yielded max. values. Aqueous digitonin solns. may lose their ability to precipitate cholesterol quantitatively as they become older. Precipitation is not complete in 3 hours at 37[degree]. The rate of precipitation appears to be independent of the amt. of cholesterol present within the range of quantities encountered in this study. A revision of the Schoenheimer-Sperry method is described. Variations in the percentage of free and total cholesterol among healthy persons within the normal range are much larger than can be explained by the error of the detn.