Extracted MRM chromatogram. The MRM transitions monitored
are provided
in Supporting Information Table S-1. Peaks
are labeled with corresponding structures. Structures in parentheses
mean they could not be specifically resolved or identified. (a) The
total dynamic MRM chromatogram monitored for a pooled human milk oligosaccharide
sample. Nine abundant HMO compounds can be readily identified and
annotated. (b) Lower abundant HMOs are identified and annotated: blue
circles, Glc (glucose); yellow circles, Gal (galactose); blue squares,
GlcNAc (N-acetylglucosamine); yellow squares, GalNAc
(N-acetylgalactosamine); red triangles, Fuc (fucose);
purple diamonds, Neu5Ac (N-acetylneuraminic acid).