An Enzymic Method for Determination of the Ratios of Esterified Cholesterol to total Cholesterol in Serum Lipoproteins

Abstract

An enzymic method is described for determination of the ratios of esterified cholesterol to total cholesterol in serum lipoproteins.
Human serum lipoproteins were separated by electrophoresis using an agarose gel plate with two sample troughs. After electrophoresis, the gel plate was cut in two parts, and these were separately stained by overlaying commercially available enzymic reagents for determination of total cholesterol and free cholesterol respectively, in order to recognize the positions of lipoproteins in the gels. Thereafter, each lipoprotein area was cut out of the gels and stained in tubeswhich contained the corresponding enzymic reagents.
After staining, the solutions in tubes were analyzed by photometer and the distribution ratios of these cholesterols to each lipoprotein were calculated from the ratios Chol of each lipoprotein to total lipoproteins in optical density. Then, the amount of T. Chol, F. and also the ratios of esterified cholesterol to total cholesterol in each lipoprotein were calculated by multiplying of these distribution ratios with these cholesterol concentrations in serum.
This method needs no special instrument and technique except those in conventional examination, so that it is simple to perform. It has sufficient reproducibility and sensitivity.