SILVER ION HIGH-PRESSURE LIQUID-CHROMATOGRAPHY PROVIDES UNPRECEDENTEDSEPARATION OF STEROLS - APPLICATION TO THE ENZYMATIC FORMATION OF CHOLESTA-5,8-DIEN-3-BETA-OL

We report that silver ion HPLC provides remarkable separations of C-27 sterols differing only in the number or location of olefinic double b onds. This technique has been extended to LC-MS, analysis of purified components by GC, CC-MS, and H-1 NMR, and to its use on a semipreparat ive scale. The application of this methodology for the demonstration o f the catalysis, by rat liver microsomes, of the conversion of 7-dehyd rocholesterol to cholesta-5,8-dien-3 beta-ol is also presented.