Matrix-assisted laser desorption/ionization mass spectrometry of neutral and acidic oligosaccharides with collision-induced dissociation

Analysis of carbohydrates and glycoconjugates by matrix‐assisted laser desorption/ionization mass spectrometry: An update covering the period 1999–2000

“…The high velocity of ions in TOF instruments has been used to impart relatively high energy in collision with gas molecules as recently demonstrated by two reports (Mechref, Baker, & Novotny, 1998;Spina et al, 2000) with TOF instruments fitted with a collision cells. Helium gave prominent 1,5 X-type ions, similar to those seen with a sector instrument (Spina et al, 2000) (Fig.…”

“…4). These ions were not seen when argon was used as the collision gas (Mechref, Baker, & Novotny, 1998;Spina et al, 2000) and they are also absent from CID spectra recorded with Q-TOF instruments, presumably because of the lower velocity of the ion beam. Differences in the fragmentation patterns of the…”

Laser‐induced photofragmentation of neutral and acidic glycans inside an ion‐trap mass spectrometer

“…[3][4][5] Not surprisingly, different combinations of ionization techniques, ion activation and mass analyzers will yield results of different analytical utility. Examples of such combinations, over the years of research on the MS/MS of glycans, include fast atom bombardment (FAB)-MS, [7][8][9] infrared-laser desorption MS, 10,11 matrixassisted laser desorption/ionization (MALDI)/magnetic sector MS, [12][13][14] electrospray ionization (ESI)-MS, 15,16 MALDI/time-of-flight (TOF)-MS, [17][18][19] ESI ion-trap MS, 20,21 MALDI Fourier transform MS, 22 ESI-or MALDI-based quadrupole/TOF-MS, [23][24][25][26] and, more recently, MALDI-TOF/TOF-MS. [27][28][29][30][31] Extensive CID has particularly been demonstrated through the tandem time-of-flight (TOF/TOF) approach, [27][28][29][30][31] yielding numerous cross-ring product ions of analytical value, such as those distinguishing between different sialic acid linkages as well as their variable attachment to a glycan antenna. 28 Alternatively, a more selective cross-ring fragmentation might be achieved through irradiation with laser light (photofragmentation), as recently demonstrated in our preliminary communication 32 on linear oligosaccharides and glycans derived from human milk.…”

New hyphenated methodologies in high‐sensitivity glycoprotein analysis

“…As the low-energy CID in the IT analyzers [32,34,44] or the PSD in MALDI/TOF MS instruments [45] is generally insufficient to accomplish this fragmentation task, we have chosen a MALDI/TOF/TOF MS with high-energy CID capabilities to furnish extensive fragmentation of model neutral [46][47][48][49][50] and acidic [46,51] glycans. An alternative approach pursued elsewhere for extensive fragmentation of glycans involves Fourier transform ion cyclotron resonance MS used in conjunction with sustained offresonance irradiation (SORI) [52], CID [52,53], IR multiphoton dissociation (IRMPD) [54][55][56], or electron capture dissociation (ECD) [54,55].…”