Gas chromatography-mass spectrometry-based trimethylsilyl-alditol derivatives for quantitation and fingerprint analysis of Anemarrhena asphodeloides Bunge polysaccharides

Here we report a novel approach using gas chromatography mass spectrometry (GCeMS)-based trimethylsilylalditol (TMSA) derivatives for simultaneous baseline separation and detection of 8 neutral saccharides and 2 uronic acids within 25 min. Using mild alkaline conditions to dissolve the sample in advance significantly increased both the detection sensitivity and sample stability of uronic acids because of occurrence of de-lactonization, whereas no obvious effects were observed for neutral saccharides. Sodium borohydride reduction of the carbonyl group of aldoses and the subsequent formation of TMSA derivatives simplifies GCeMS chromatograms by producing a single peak for each derivatized sugar. The effects of both reaction temperatures and solvent ratios between HMDS and TMCS on formations of TMSA derivatives were also investigated. The established GCeMS method was successfully applied for quantitation and fingerprint analysis of polysaccharides from the plant Anemarrhena asphodeloides Bunge. A comparative analysis of A. asphodeloides polysaccharides was further performed between TMSA and other four types of derivatizations. The results showed that GCeMS analysis based on precolumn TMSA derivatization coupled with fingerprint analysis is a comprehensive and effective technique for qualitative and quantitative analysis of plant polysaccharides from traditional Chinese medicines.