A robust boronic acid-integrated olefin-linked covalent organic framework (BACOF) was synthesized via a straightforward one-step Knoevenagel condensation. The material combines exceptional structural stability, high surface area, inherent boronic acid affinity, and enhanced hydrophilicity, resulting in outstanding glycopeptide enrichment performance. It exhibits an ultra-low detection limit (0.05 fmol·µL⁻ 1 ), high selectivity (HRP: BSA = 1:500), large binding capacity (80 mg·g⁻¹), excellent reusability (7 cycles), and satisfactory recovery (92.5 ± 1.5%). In nano LC-MS/MS analysis of clinical serum samples, BACOF enabled the identification of 250 glycopeptides (from 91 glycoproteins and 212 N-glycosylation sites) in laryngeal cancer patients, and 268 glycopeptides (from 121 glycoproteins and covering 235 N-glycosylation sites) in healthy controls. Label-free quantitative proteomics further revealed that dysregulated glycoproteins were coordinately enriched in immune and vascular-related processes. Five hub glycoproteins, antithrombin-III (SERPINC1), beta-2-glycoprotein 1 (APOH), transthyretin (TTR), alpha-1-acid glycoprotein 1 (ORM1), and vitronectin (VTN), were identified as promising candidate biomarkers for laryngeal cancer. This study establishes olefin-linked COFs as a robust and versatile platform for advanced glycoproteomics and clinical biomarker discovery.
Meng et al. (Thu,) studied this question.