Heparin--magnesium chloride--albumin method for enzymic measurement of cholesterol in high-density lipoprotein.

We describe a new method for measuring high-density-lipoprotein cholesterol in sera, with use of heparin, MgCl2, and albumin to precipitate very-low- and low-density lipoproteins, Lipoprotein electrophoresis and immunochemical methods show that high-density lipoprotein is completely and specifically isolated in the supernate, the cholesterol concentration of which is estimated by the enzymic method of Allain et al. (Clin. Chem. 20, 470, 1974). The precision of the method is excellent (CV = 1%) and the response is linear. Values so obtained correlate well with those obtained with the heparin-Mn2+ (r = 0.98) or the phosphotungstate-Mg2+ (r = 0.98) procedures. The technique is appropriate for routine clinical laboratory use.