Identification of the individual molecular species of ceramides derived from human erythrocytes using HPLC/MS and HPLC/MS/MS

A preparative separation of total ceramide fraction from the crude extract of the erythrocytary lipids was done by means of normal-phase column chromatography. This was followed by comprehensive profiling of the molecular species in the obtained ceramide by means of HPLC/MS and HPLC/MS/MS. The MS/MS analysis displayed that human erythrocytes contain 19 molecular species of the ceramide of which 12 can be unambiguously identified; erythrocytary ceramides may contain not only sphingosine but also sphinganine as their building blocks; one of the species (namely Cer 24:2/S18) previously has managed to escape identification. We also obtained a quantitative profile of major ceramide species showing the prevalence of Cer 22:0/S18, 24:0/S18 and 24:1/S18.