Enzymic determination of cholesterol in serum lipoproteins separated by electrophoresis

We describe a reliable, straightforward procedure for measuring the cholesterol content of serum lipoproteins separated by electrophoresis on cellulose acetate. The lipoprotein fractions are made visible by use of an enzymic reagent and then quantitated by densitometry. Standard electrophoresis equipment is used and the procedure requires just over 1 h for completion. All major fractions except chylomicrons are detected readily. Accuracy and precision agree favorably with results reported for generally accepted methods. Concentration and color development are linearly related to cholesterol concentrations up to 1.5 g/liter in a given lipoprotein fraction. We recommend this method for use in assessing high-density lipoprotein cholesterol and as an aid in lipoprotein phenotyping.