Separation and Quantification of Phospholipid and Neutral Lipid Classes by HPLC–CAD: Application to Egg Yolk Lipids

In this paper the methods of different lipid classes analysis using high performance liquid chromatography (HPLC) with charged aerosol detector (CAD) are presented. The methods allowed base-line separation of all investigated egg yolk phospholipids (phosphatidylcholine, PC; phosphatidylethanolamine, PE; sphingomyelin, SM; and their lyso forms) and neutral lipid classes (triacylglycerol, TAG; cholesterol, Chol). Total lipids extraction was carried out by the Folch method. The polar and neutral lipid classes were separated by using normal-phase (silica) SPE cartridges. Two different HPLC methodologies (one for polar and one for neutral lipids) for the separation and quantification of lipid classes on a diol column were applied. The methods were optimized and the response and sensitivity of CAD was studied. In terms of linearity, precision, and sensitivity the methods were validated.