HIGH-MASS GAS-CHROMATOGRAPHY MASS-SPECTROMETRY OF PERMETHYLATED OLIGOSACCHARIDES

This chapter discusses high-mass gas chromatography-mass spectrometry of permethylated oligosaccharides. Capillary gas chromatography-mass spectrometry (GC/MS) is a fast, sensitive, and high-resolving method for the characterization of biomolecules. It has been used in glycoconjugate research for analyzing the partially methylated alditol acetates after degradation of the glycoconjugates and, in a few cases, for the analysis of oligosaccharides after permethylation or trifluoroacetolysis. The advent of high-temperature capillary GC using thin-film thermostable bonded stationary phases now allows the analysis of large permethylated oligosaccharides, an adaptation that should also be useful in other fields of biomedical research. Oligosaccharides released from neutral glycosphingolipids and gangliosides have been successfully analyzed, as well as similar oligosaccharides found in free form in, for example, milk. Oligosaccharides released from mucins and other glycoproteins by alkaline-NaBH4 treatment can be analyzed and the high resolution achieved is necessary for separating the complex mixtures found in nature. Permethylation using solid NaOH gives good yields for neutral oligosaccharides with a GalNAc-alditol, and neutral and sialic acid-containing oligosaccharides with a Glc-aldose. © 1990, Elsevier Inc. All rights reserved.