Mass spectrometry for structural elucidation and sequencing of carbohydrates

Carbohydrates are the most abundant organic compounds in nature, widely distributed in animals, plants and microorganisms. In order to understanding their structure properties, the following critical aspects should be revealed: a) building blocks (compositional monosaccharide); b) glycosidic linkages and anomeric configuration; c) sequence of sugar residues; d) molecular mass or degree of polymerization; e) substitutions. Mass spectrometry (MS) is a powerful technology for carbohydrate analysis. The development of ionization sources and mass analysers, as well as the possibility in coupling with different separation methods, extend their potential to carbohydrates research. Therefore, in this review, the research progress of carbohydrates investigated by MS technologies was summarized, mainly emphasized on how their structural features were elucidated, and a brief description of their applications in characterizing herbal and food polysaccharides, as well as proposing some suggestion of future development prospects.