MS spectra of (a) CH2DI permethylated fucosylated glycan, (b)
13CH3I permethylated fucosylated glycan, (c) CH2DI permethylated trisialylated triantennary glycan, and (d)
13CH3I permethylated trisialylated triantennary glycan. The glycans were released from model glycoprotein mixture (RNaseB, fetuin, and IgG), 8-plex permethylated and mixing at a ratio of 1:1:1:1:1:1:1:1 before analysis on LC-MS. Peaks with astarlikes indicate impurity peaks influenced by isotopic labeling iodomethane reagents purity. Symbols as in Table 1.