Gas Chromatography-Mass Spectroscopy (GC-MS)
Gas Chromatography GC-MS is used for the quantification and accurate identification of monosaccharides originating from plant and microbial polysaccharides and glycoconjugates. The technique is also used for determining linkage positions in residues composing oligosaccharides or polysaccharides.
- For monosaccharide composition analysis, the sample is hydrolyzed with an acid to form methyl glycosides, which are subsequently derivatized for GC analysis by electron impact setting (EI).
- Uncommon or unidentified residues detected by EI setting are further evaluated through chemical ionization (CI) setting to obtain molecular weights, which are matched with the EI information to deduce possible glycosyl identification.
- Glycosyl linkage analysis is accomplished by subjecting the sample to permethylation procedure, hydrolysis, and acetylation of hydroxyls to form partially methylated alditol acetates (PMAAs).
- PMAAs are analyzed by GC-MS and a free access database is available at CCRC.
- The CCRC Analytical Services Laboratory has five (5) units of Agilent GC-MS with EI, one (1) Shimadzu GC-MS with CI setting and one (1) GC-FID.