Analysis of energy-resolved mass spectra at MSn in a pursuit to characterize structural isomers of oligosaccharides.

Analyses of energy-resolved mass spectra (ERMS) of structural isomeric oligosaccharides were carried out under collision-induced dissociation conditions at different stages of MSn. Quantitative analyses of energy-resolved curves revealed that these curves can be used to distinguish anomeric configurations and such analysis can be made regardless of the stages of MSn. Furthermore, parameters obtained from the sigmoidal shaped curves obtained for ERMS were found to be used as the structural descriptors after statistical analysis. An important finding is that analyses of these descriptors depend on neither the m/z values nor the height factors.