Separation and identification of ceramides in the human stratum corneum byhigh-performance liquid chromatography coupled with electrospray ionization mass spectrometry and electrospray multiple-stage mass spectrometry profiling

A sensitive. selective and rapid method is described for analysis of cerami des in the human stratum corneum by direct coupling of HPLC with an electro spray ion-trap mass spectrometry. Nonaqueous reversed-phase chromatography stabilizes the electrospray ionization, resulting in sensitivity that enabl es direct measurement of skin lipid extracts with no special sample prepara tion. Assignment of individual signals to the corresponding ceramide specie s is based on interpretation of the fragment spectra from MS-MS experiments . This enables much finer differentiation between ceramides than that achie vable by thin-layer chromatography.