Glycosphingolipids MALDI

Guittard, J. Hronowski, X.L. Costello, C.E. Direct MALDI Mass Spectrometric Analysis of Glycosphingolipids on Thin Layer Chromatographic Plates and Transfer Membranes. Rapid Commun. Mass Spectrom. 1999,13, 1838-1849. 

ESI, like MALDI is compatible with negative- and positive-mode analyses and for analysis of native or permethylated neutral glycosphingolipids. The most abundant signal is also often the singly sodiated ion [M + Na]+. In-source fragmentation can be tuned by varying the ion source temperature and skimmer voltage. 

Colsch B, Woods A (2010) Localization and imaging of sialylated glycosphingolipids in brain tissue sections by MALDI mass spectrometry. Glycobiology 20 661-667. doi 10.1093/glycob/ cwq031... 

Gold nanoparticles have also been used, by Nishimura and Tseng, as an assisted matrix for determining neutral small carbohydrates, employing MALDI-TOF MS. GNP-assisted MALDI-TOF MS enables an enrichment analysis of Uving-cell-surface glycosphingolipids. ... 

Structurally, glycosphingolipids and gangliosides are distinct from other classes of lipids they are made of a hydrophobic ceramide lipid tail to which an oligosaccharide head group is attached. Characterization of glycosphingolipids and gangliosides is achieved by CID-MS/MS of the FAB-, ESI-, and MALDI-produced [M - - H]+ and [M — H] ions. Structural information on ceramide and carbohydrate portions can be also derived. 

On-hne high-performance TLC (HPTLC) MALDI-FT-MS at elevated pressures was described in the direct analysis of gangliosides from TLC plates using soHd matrices [176]. Gangliosides are glycosphingolipids that contain one or more siahc... 

An excellent, timely review regarding applications of MALDI MS to characterize glycosphingolipids (GSL) has been recently published [34] and this is the reason why we will mention here only a few selected highlights. In an early MALDI attempt [35], native GSL were separated on a conventional (silica gel 60) TLC plate by using... 

Sphingolipids have been studied by soft-ionization methods, with FDl-MS, FAB-MS, ESI-MS, and MALDI-MS being the most widely used techniques. FDl-MS was applied for the characterization of glycosphingolipids with up to five saccharide units [213], Both FDI-MS and LSIMS-MS were apphed in the analysis of acidic glycosphingolipids, i.e., carrying asialo or sulfatide units [214]. In both cases, both [M+H]+ and [M+Na] was observed, whereas with the acidic compounds [(M-H+Na)+Na] -ion were observed as well. Similar observations have been made using other condensed-phase ionization methods [215, 216]. 

IM-MS is particularly useful for analysis of isobaric and isomeric lipid species, which possess different structures or configurations. For example, MALDI-IM MS has been used to analyze gangliosides, a class of complex glycosphingolipids... 

Figure 12.11. Imaging-mode MALDI-IM-MS of a thin tissue section (16 rm) of a rat brain, (a) Structures of glucosylceramide and galactosylceramide, the two major classes of cerebroside molecules. Both cerebrosides are glycosphingolipids, which are impmlant components in nerve cell membranes, (b) Integrated mass spectrum obtained at the specific IM-ATD for these cerebrosides directly from rat brain tissue, (c) False color image of signal intensity for where these cerebrosides occur spatially in the context of the thin tissue section. Imaging MALDI-IM-MS was perfimned at 349 nm using a 2-nm Au nanoparticle matrix, with an imaging spatial resolution of 200 pm.

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