Liquid chromatography–electrospray mass spectrometry and tandem mass spectrometry of ceramides Original Research Article

A quantitative liquid chromatography–mass spectrometry (LC/MS) method designed for the rapid, sensitive and specific analytical determination of all kinds of ceramides is described. LC separation was carried out on a RP 18 column (2 mm i.d., 3 μm particle size) using an isocratic mobile phase (methanol/tetrahydrofuran 97 : 3) in less than 8 min. LC/MS and LC/MS/MS were performed on an ion trap instrument and were compared to results obtained using a single quadrupole instrument. In the negative ionization mode a limit of detection of approx. 500 pg/ml was reached. The quantification using external standards showed good linearity over three orders of magnitude and a relative standard deviation of 3%. The use of Tandem MS and MS3 for obtaining structural information was demonstrated on the ion trap instrument and compared to results achieved on a triple quadrupole instrument.