Rapid isolation of large amount of plasma VLDL and LDL by a two step ultracentrifugation.

A rapid method to obtain large amount of VLDL and LDL by ultracentrifugation is described. The mixture of VLDL and LDL was isolated and concentrated from plasma by an ultracentrifugation at 265 000 g for 2 h. VLDL and LDL were separated and purified by a further ultracentrifugation at 265 000 g for 3 h. This method combines the advantages of both sequential flotation ultracentrifugation and density gradient ultracentrifugation. It can process a large volume of plasma in a short time. The purity of isolated VLDL and LDL was confirmed by the lipoprotein electrophoresis on agarose gel and PAGE and by the apolipoprotein electrophoresis on SDS-PAGE. This rapid economical method is of great value in practical application.