Self-Assembling Glutamate-Functionalized Cyclodextrin Molecular Tube for Specific Enrichment of N-Linked Glycopeptides

Cyclodextrin molecular tube (CDMT), a new comer of cyclodextrin family, possesses large and hydrophilic outer area and stable structure. Its development and applications remain highly desired, especially in the field of separation and enrichment. Herein, we developed a CDMT-based enrichment platform focusing on the specific capture of glycopeptides. To enhance the hydrophilicity of CDMT, it was functionalized with glutamate (glu). The prepared gluCDMT exhibited large hydrophilic surface, high stability, and good acidic/alkalic resistance. A solid monolithic support was employed to immobilize gluCDMT by a host–guest self-assembly synthetic strategy, which did not occupy the surface hydrophilic sites. The gluCDMT-based monolith exhibited high binding capacity (∼50 mg g–1), good ability to capture glycopeptides (23 HRP glycopeptides and 28 IgG glycopeptides), and high selectivity (horseradish peroxidase/bovine serum albumin = 1:10 000). Moreover, the developed platform was successfully applied to analyze glycopetides in acute myelogenous leukemia cell lysate and human serum samples.