Hydrophilic probe in mesoporous pore for selective enrichment of endogenous glycopeptides in biological samples

As one of the most important post-translational modifications (PTMs) of peptidome, glycopeptidome is closely related to serious disease, especially to cancer. In order to specifically discover and analyze glycopeptidome biomarkers for clinical diagnosis of cancer on early-stage, it is crucial to develop efficient technique to analyze low-abundance of endogenous glycopeptides in biological samples. In this report, a hydrophilic probe in mesoporous pore (denoted as Fe3O4@mSiO2@G6P) was designed and prepared. By taking advantage of the excellent hydrophilicity and size-exclusion ability, we applied Fe3O4@mSiO2@G6P to capture glycopeptides from both horseradish peroxidase (HRP) and immunoglobulin (IgG) digests successfully. Moreover, a total of 39 and 25 endogenous glycopeptides were identified from healthy saliva and gastric saliva, respectively, indicating the great potential of this probe for the exploration of glycopeptidome biomarkers. [Display omitted] •Profiling of glycopeptidome is significant toward the discovery of disease biomarkers.•The Fe3O4@mSiO2@G6P probe with excellent hydrophilicity and size-exclusion effect was synthesized facilely.•The hydrophilic probe exhibited excellent enrichment performance for endogenous glycopeptides.•The probe was successfully employed to capture endogenous glycopeptides from bio-samples of human saliva.