A new chemical procedure for selective sequential separation of serum lipoproteins

A new chemical procedure for selective sequential separation of serum lipoproteins is described. Low density lipoproteins (LDL) were precipitated by polyvinylsulfate and the precipitates were redissolved in NaCl 0.45 mol/l. Very low density lipoproteins (VLDL) were precipitated from LDL-free supernatants by PEG-6000 at 100 g/l final concentration, pH 10, and the precipitates were redissolved in NaCl 0.15 mol/l. For the precipitation of high density lipoproteins (HDL), apolipoprotein B-free supernatants were treated by PEG-6000 at 266 g/l final concentration and the precipitates were redissolved in NaCl 0.15 mol/l. The procedure was effective up to a serum triglyceride concentration of 4.0 mmol/l as well as in serum samples without chylomicrons or remnants. The determination of cholesterol and triglyceride contents in separated lipoproteins allows the study of their chemical composition in normo- and moderately hypertriglyceridemic serum samples.