Separation of lipid classes by chromatography on florisil

Abstract

Chromatography on Florisil® (activated magnesium silicate) was used to separate model compounds representative of hydrocarbons, cholesterol esters, triglycerides, free sterols, diglycerides, monoglycerides, and free fatty acids. The order of elution was the same as that observed in silicic-acid chromatography except that free fatty acids were eluted after monoglycerides. Recoveries were nearly quantitative and the positions of individual compounds on the chromatograms were highly reproducible. Phospholipids were not eluted under the conditions used for separating the above compounds, and were eluted less readily from Florisil than from silicic acid with methanol. Florisil had definite advantages over silicic acid for the separation of lipid classes by column chromatography. It required no prewashing or other pretreatment except deactivation with water. Columns were quickly and easily packed, and the relatively coarse mesh of the Florisil permitted rapid flow rates. Separations could be achieved in much shorter times with smaller volumes of eluting solvents. Preliminary experiments indicated that chromatography on Florisil gave good separations of lipid classes of naturally occurring lipids extracted from liver and blood.