“…10 Nonetheless, the low efficiency of ionization of N-glycopeptides and their low concentration from actual samples make it very hard to analyze them directly by MS. 11 Therefore, before performing MS analysis, it is crucial to create novel materials for effective N-glycopeptide enrichment. 12,13 Currently, the technologies for the enrichment of N-glycopeptides include the boric acid method, 14 lectin affinity chromatography, 15 hydrophilic interaction (HILIC) method, 16,17 and hydrazide chemistry. 18 Among them, the HILIC method has the advantages of unbiased enrichment ability, high sensitivity, and simple operation.…”