Separation of Polar Lipid Classes into Their Molecular Species Components by Planar and Column Liquid Chromatography

As a rule, polar glycerolipids * of biological membranes are represented by several classes. Each class includes substances (lipid molecular species) with identical hydrophilic headgroups but they differ from each other by the nature of their diacylglycerol (acy 2 Gro) radicals. Therefore, each individual molecular species within a given lipid class is characterized by a definite number of carbon atoms (m i ) and olefinic linkages (e i ) in acyl 2 Gro fatty acid residues. The molecular species composition (“fine structure”) of a lipid class is defined as the qualitative composition and quantitative content of individual molecular species. The quantitative content is expressed as a mole percent of the total concentration of all the lipid molecular species composing the given class [ 1 ].