Structural studies on ceramides by electrospray tandem mass spectrometry

A rapid and simple method for the characterization of different species of ceramides is presented. Electrospray MS/MS was used as a powerful tool for the identification of the acyl component as well as the long-chain sphingoid base. The MS/MS spectra obtained by positive ionization show only unspecific dehydrations. In contrast, the negative spectra provide detailed information. The instrumental conditions were optimized to obtain fingerprint spectra in one step. The probable structures of the fragments are shown in fragmentation schemes.