Laremore Tatiana N, Zhang Fuming, Linhardt Robert J
Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, New York 12180, USA.
Anal Chem. 2007 Feb 15;79(4):1604-10. doi: 10.1021/ac061688m.
Polyanionic oligosaccharides such as dermatan sulfate (DS) and chondroitin sulfate (CS) exhibit poor ionization efficiencies and tend to undergo thermal fragmentation through the loss of SO(3) under conventional ultraviolet matrix-assisted laser desorption/ionization (UV-MALDI) conditions. A new ionic liquid matrix (ILM), a guanidinium salt of alpha-cyano-4-hydroxycinnamic acid, facilitates direct UV-MALDI mass spectrometric (MS) analysis of underivatized DS and CS oligosaccharides up to a decasaccharide in their common form as sodium salts. The resulting mass spectra show very low extent of fragmentation through an SO(3) loss. The new ILM is suitable for MALDI-MS analysis of mixtures containing oligosaccharides with different numbers of sulfo groups.
诸如硫酸皮肤素(DS)和硫酸软骨素(CS)之类的聚阴离子寡糖在传统的紫外基质辅助激光解吸/电离(UV-MALDI)条件下表现出较差的电离效率,并且倾向于通过失去SO(3)而发生热裂解。一种新型离子液体基质(ILM),即α-氰基-4-羟基肉桂酸的胍盐,有助于对未衍生化的DS和CS寡糖(以其常见的钠盐形式,直至十糖)进行直接UV-MALDI质谱(MS)分析。所得质谱显示通过失去SO(3)的裂解程度非常低。这种新型ILM适用于对含有不同磺酸基团数量的寡糖混合物进行MALDI-MS分析。