Separation of Steroids by Gas Chromatography

Effects of Varying the Chemical Composition of the Stationary Phase on the Separation of Certain C19,and C21,and C27 Steroids by Gas Chromatography

“…At this stage of development, the use of capillary columns for the resolution of the indiyidual components of complex mixtures of steroids nil1 require more exacting techniques of uniformly and optimally coating these narrow bore tubes nith specific liquid phases. It would appear that this is essential since the analysis of steroids on packed columns n as made practical only by the use of thin eoab ings of stationary phase (12). Earlier studies (1, S ) performed with more conrentional concentrations (above 6%) of liquid phase required operating temperatures of 250" to 300" C. This range of temperatures imposed heavy restrictions upon the selection of the stationary phase, since very few polar polymers are thermally stable beyond 250' C.…”

Effects of Triparanol (Mer-29) on Cholesterol Biosynthesis and on Blood Sterol Levels in Man*

“…late the two specific radioactivities individually, even though the desmosterol was contaminated with a small amount of cholesterol and vice versa. Separation of sterols by gas-liquid chromatography was done according to vanden Heuvel, Sweeley and Horning (21). The column was packed with Chromosorb W, coated with silicone rubber (G.E.…”

Biosynthetic origin of serum cholesterol in the squirrel monkey: evidence for a contribution by the intestinal wall

“…First, the neutral sterol fractions from 21 different tissues were analyzed by gas-liquid chromatography with 6 ft columns containing 3% QF-1 (methyl fluoroalkyl silicone) on GasChrom Q at a column temperature of 230'C and an argon flow of 100 ml/minute (23). Under these conditions a peak corresponding to cholesterol was the only identifiable sterol peak in all tissues except for skin and hair, in which a second peak was present, corresponding to 0.73 and 0.14 out of 3.25 and 2.44 mg of total sterol/g of tissue; the second peak in these tissues had the chromatographic properties both in this system and on thin-layer chromatography (24) of A7-cholestenol.…”