Some observations on the chromatographic behaviour of phosphatidylserine

Abstract

An indication is given of the nature of the material corresponding to the three peaks occurring when most samples of phosphatidylserine (fraction ELI, Folch, 1942) are chromatographed on silicic acid [long dash] Hyflo Super-Cel columns. Exchange of lipid sodium or potassium for another cation, presumably H+ ions, occurs on the columns causing the elution of lipid with chloroform-methanol (4:1, v/v). This can be prevented by treatment of the adsorbent with hydrochloric acid followed by sodium hydrogen carbonate. Exchange of lipid potassium for sodium occurs on the columns. The chromatographic mobility of phosphatidylserine depends upon the metal ion combined with the lipid. Application of the calcium and magnesium forms to the column results in the elution of the lipid with chloroform-methanol (4:1, v/v). When the sodium or potassium forms are applied, the bulk of the lipid is eluted with chloroform-methanol (3:2, v/v).