Abstract
Mass spectrometric analyses of glycoconjugates are most commonly performed by fast atom bombardment (FAB) or liquid matrix-assisted secondary ion mass spectrometry (SIMS). However, more recent ionization methods, such as electrospray (ESI) and matrix-assisted laser desorption (MALD), have made mass spectrometric analyses applicable to even larger, thermally labile biomolecules. ESI often produces multiply-charged ions, and a molecular weight is obtained by the deconvolution of those multiply-charged ions. On the other hand, MALD may produce intact molecular ions up to half a million daltons. Combination of high performance liquid chromatography with mass spectrometry (HPLC-MS) is often a strategy of choice for biological samples in which contamination of other chemical species is usually unavoidable. Tandem mass spectrometry (MS/MS) with collision-induced dissociation (CID) often provides structural information for unknown sample molecules. In particular, charge-remote fragmentation applying a high-energy collision sometimes gives detailed information about the locations of unsaturation and branchings of metal-cationated molecules.
