A chromatographic and mass spectrometric strategy for the analysis of oligosaccharides: determination of the glycan structures in porcine thyroglobulin.

Oligosaccharides released from porcine thyroglobulin were first derivatised with 2-aminoacridone (2-AMAC) and analysed by capillary electrophoresis to determine the complexity of this glycan pool. The same glycan mixture was then subjected to either a sialidase digest or a sialidase and fucosidase digest prior to derivatisation with 2-AMAC and analysis by normal phase high pressure liquid chromatography (HPLC). Comparison of the three chromatographic profiles with known standards allowed an initial identification of the glycan structures. The 2-AMAC derivatised glycans were then collected from HPLC for matrix-assisted laser desorption/ionisation time-of-flight (MALDI-TOF) analysis and the molecular weights of predicted structures were confirmed. This study demonstrates that a two enzyme array and subsequent MALDI-TOF analysis can be used successfully to assign the major glycans present in a complex mixture.