Reversed-phase separations of nitrogenous phospholipids on an octadecanoyl poly(vinyl alcohol) phase

Molecular species of nitrogenous phospholipids (PLs) phosphatidylcholine (PC), phosphatidylethanolamine (PE), PE- derivatives and sphingomyelin (SP) were separated on an octadecanoyl poly(vinyl alcohol) (ODPVA) column by reversed-phase HPLC with UV and evaporative light scattering detection (ELSD). Mobile phases employed variable proportions of acetonitrile, methanol and water. HPLC–UV of the polar lipids yielded components with peak intensities somewhat different from those obtained by HPLC–ELSD despite discernible similarity in the peak profiles observed in the two detection systems. Incorporation of ammonium hydroxide in mobile phases resulted in a decrease in analyte retention. The mobile phase basicity effect on capacity factors of PE species was significantly greater than that of PC counterparts. The new ODPVA HPLC–ELSD technique was applied to the analysis of PC and PE molecular species in vegetable oils.