Figure 5.

Determination of the fucosylation pattern based on HILIC-IM-MS. (A) Extracted ion chromatogram (EIC) of a doubly sialylated biantennary glycan with one fucose attached (m/z = 1295). Minor peaks marked with an asterisk are fragment ions generated from larger glycans. (B) MS/MS spectra of the precursor ions 5–8, which are almost identical and show the dominant B₃ trisaccharide fragment. One major difference stems from either Y₂ fragmentation (highlighted in blue) or B₃ fragmentation (highlighted in red). (C) Mobilograms of the B₃ + fucose fragment generated from precursor ion 7. Comparison with a synthetic standard (3′-Sialyl-Lewis-X) allows us to identify the fucose isoforms and confirm the native state of the fucosylation.