Gas--liquid chromatography-mass spectrometry of synthetic ceramides.

Two series of ceramides with either sphingosine (sphing-4-enine) or sphinganine as base and with one of the saturated fatty acids C(16), C(18), C(20), C(22), C(24), C(26), or oleic acid were analyzed as the 1,3-di-O-trimethylsilyl ether derivatives by gas chromatography-mass spectrometry. The fragments formed on electron impact can be divided into three main groups, namely "molecular weight fragments," "long-chain base fragments," and "fatty acid fragments." The m/e values of these fragments can be used to determine unequivocally the structures of the long-chain base and fatty acid of a ceramide derived from a sphingolipid.