FIGURE 3.

GC-MS methylation linkage analysis of aq. HF-released glycans. The sample recovered from NMR analysis was reduced with NaBD₄ and converted to PMAAs for analysis by GC-MS. A, total ion chromatogram (TIC) of the PMAA derivatives of the monosaccharide constituents, annotated using descriptors that are explained in Table 5. The PMAA identities were inferred from their retention times and electron impact mass spectra. B, electron impact mass spectrum and spectrum assignment (inset) of the 3,4-disubstituted-GlcNAc-ol PMAA from A.