On-line liquid chromatography/thermospray mass spectrometry in the analysis of oligosaccharides.

The analysis of intact neutral oligosaccharides by on-line liquid chromatography/thermospray mass spectrometry is described. Molecular-weight information on oligomers up to a degree of polymerization of 10 is obtained using an aqueous mobile phase containing 10(-4) mol/L sodium acetate, which was found to be compatible with thermospray interfacing and ionization. Ions due to sodiated and disodiated oligosaccharides are observed under these conditions without fragmentation. The aqueous 10(-4) mol/L sodium acetate mobile phase is demonstrated to be applicable in the separation of mixtures of oligosaccharides on a reversed-phase octadecyl-modified silica column.