Analytical separation of nonlipid water soluble substances and gangliosides from other lipids by dextran gel column chromatography

A column chromatographic procedure is reported utilizing a dextran gel (Sephadex) for the complete separation of the major lipid classes from water-soluble nonlipids. Lipids other than gangliosides are eluted first with chloroform/methanol 19/1 saturated with water, gangliosides with chloroform/methanol/water containing acetic acid, and water-soluble nonlipids with methanol/water 1/1. Results for adult human whole brain, grey and white matter, and normal infant whole brain lipids are presented. With beef brain lipid as sample the ganglioside fraction is essentially pure, but with human brain lipid samples only about 70% of the second fraction is ganglioside. All ganglioside and water soluble nonlipid of a human spleen chloroform/methanol extract was separated from lipids with the procedure. Control studies with P³²O₄≡ and C₁₄ labelled glucose showed that all counts were present in fraction 3. Similar studies with C₁₄ labelled amino acids (glycine, serine, alanine, phenylalanine) showed that only phenylalanine counts were eluted in fraction 2 along with the gangliosides. The procedure was applied for removal of large amounts of ammonium acetate from DEAE cellulose column fractions and for complete removal of adsorbent and salts from lipids eluted from thin-layer chromatograms. After passage through the dextran gel columns, lipids eluted from thin-layer chromatograms were found to give infrared spectra identical to those of pure samples obtained by other procedures.