Surface functionalization modification of ultra-hydrophilic magnetic spheres with mesoporous silica for specific identification of glycopeptides in serum exosomes

Protein glycosylation of human serum exosomes can reveal significant physiological information, and the development of large-scale identification strategies is crucial for the in-depth investigation of the serum exosome glycoproteome. In this study, using surface functionalization techniques, an ultra-hydrophilic mesoporous silica magnetic nanosphere (denoted as Fe3O4-CG@mSiO(2)) was synthesized for the quick and accurate detection of glycopeptides from HRP digests. The Fe3O4-CG@mSiO(2) nanospheres demonstrated outstanding enrichment capability, high sensitivity (5 amol/mu L), good size exclusion effect (HRP digests/BSA proteins, 1:10,000), stable reusability (at least 10 times), and an excellent recovery rate (108.6 +/- 5.5%). Additionally, after enrichment by Fe3O4-CG@mSiO(2), 156 glycopeptides assigned to 64 proteins derived from human serum exosomes were successfully identified, which demonstrates that the nanospheres have great potential for the research of the large-scale serum exosome glycoproteome.