Electrospray ionization and collision-induced dissociation time-of-flight mass spectrometry of neutral glycosphingolipids

✍ Scribed by Anne Olling; Michael E. Breimer; Erik Peltomaa; Bo E. Samuelsson; Sohbat Ghardashkhani

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 310 KB
• Volume: 12
• Category: Article
• ISSN: 0951-4198
• DOI: 10.1002/(sici)1097-0231(19980529)12:10<637::aid-rcm207>3.0.co;2-d

✦ Synopsis

A series of native naturally occurring neutral glycosphingolipids has been analysed by electrospray ionization tandem mass spectrometry using a hybrid magnetic sector-TOF instrument. The collisioninduced dissociation products of precursor ions were detected by an orthogonal acceleration time-of-flight mass spectrometer as the second analyser. Glycosphingolipids, with mono-to hexa-saccharide chain lengths with different ceramide constituents, were studied. The result of electrospray ionization in the positive ion mode generally showed singly charged molecular ions with Na as adduct, [MNa] . The sensitivity of the electrospray ionization was greatly enhanced by addition of NaCl, LiCl (forming [MLi] ) or KCl (yielding [MK] ) to the sample. A comparison between the collision-induced dissociation of precursor molecular ions of monoglycosylceramides, using Na , Li and K as adducting species, showed that the intensity of the fragment ions and the extent of the daughter ion fragmentation of the molecular ions, are dependent on the type of adduct used. The daughter ion spectra of Li adduct ions showed intense sequence fragment ions, both of the saccharide chain and the ceramide moiety, and were superior to those obtained using Na or K . The collision-induced dissociation spectra of the [MLi] ions, of glycosphingolipids containing di-to hexasaccharides, are also presented. Proposed possible fragments, resulting from the CID of the molecular ions [MLi] of monoglycosylceramides, are shown.