LC–MS/MS analysis of chitooligosaccharides Original Research Article

Chitooligosaccharides with degrees of polymerization (DPs) 2–12 were successfully separated and characterized using LC–MS/MS analysis with an amine column and a quadrupole ion trap analyzer. Major MS peaks for each chromatographic peak originated from deacetylated chitooligosaccharides while N-acetylated chitooligosaccharides were observed as minor peaks. The ratio of acetylation per glucosamine unit for each chitooligomer was higher for oligomers with higher DPs. The MS/MS spectra of chitooligosaccharides were used to characterize the chitooligosaccharide fragmentation patterns. To the best of our knowledge, this is the first report of on-line LC–MS/MS analysis of chitooligosaccharides with DP higher than 6.