Ultracentrifugal subfractionation of high-density lipoprotein

Knowledge of the structure, function and metabolism of the plasma lipoproteins has been greatly facilitated by refinement of the high-performance ultracentrifuge. Techniques based on anglehead rotors are widely used to isolate different fractions by increasing in a stepwise fashion the plasma solvent density. This simple approach may, for various reasons, result in the selection of inappropriate density intervals and so alternative zonal procedures have been developed that yield a continuous lipoprotein spectral distribution. However, the limited analytical capacity of this kind of system has highlighted the need for more rapid microcomputer-controlled ultracentrifugation techniques. The merits of each of these approaches are discussed with reference to the subfractionation of high-density lipoproteins.