Released glycans, labeling

Figure 1.116 Released glycans can be labeled with small fluorescent compounds containing amines for subsequent detection upon chromatographic separation. In the presence of sodium cyanoborohydride these compounds react at the reducing end of glycans to form secondary amine derivatives with characteristic spectral properties.

Figure 11.20 BAP can be used to label the reducing end of released glycans by reductive amination in the presence of a reducing agent.

Labeling of the released glycans. To facilitate their detection in the subsequent procedures, the released ohgosaccharides with free reducing ends are labeled. Two methods that are commonly used to label oligosaccharides are reductive amination with a fluorescent compound, such as 2-aminobenzamide and reduction with alkaline NaB H4. 

Figure 8.7 Chromatographic profile of released glycans from a monoclonal antibody following fluorescent labeling. Sample was analyzed with a Waters BEH Glycan colunm (1.7 jim, 1.5 x 150 mm) and fluorescent detection. Reproduced with permission from Cook, K.S., et al. Biologicals. 2012.

Glycoprotein was digested using the peptide N-Glycosidase F (PNGase F) to release N-linked glycan, then labeled with 8-aminopyrene-l,3,6-trisulfonate (APTS). The detection used LIF with a argon-ion laser. 

The general form for oligosaccharide profiling is release of the glycans, derivatization (e. g. fluorescent labeling), then analysis by HPLC, CE, or MS. 

In a subsequent experiment, pH]Gal-labeled 0-glycans were released by... 

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