A Diazirine/NHS Dual-Anchor Microarray Chip Enables Immobilization of Synthetic Oligosaccharides, Glycolipids, and Native Polysaccharides

Conventional microarray chemistries are generally optimized for amine-bearing probes, whereas native polysaccharides and glycolipids often require prior derivatization for immobilization, which risks altering key carbohydrate epitopes. Here, we developed a dual-anchor microarray platform ( DAMP ) by modifying commercially available poly-L-lysine-coated slides with NHS esters and diazirine photo-crosslinkers. The key innovation of this platform is the complementary dual-chemistry design on a high-loading 3D surface: NHS chemistry enables efficient immobilization of amine-bearing probes, whereas diazirine-mediated photo-crosslinking enables derivatization-free capture of underivatized native glycans. The resulting platform enabled rapid immobilization of native polysaccharides and glycolipids under mild UV irradiation and showed markedly enhanced sensitivity for amine-bearing glycans:10   pg/mL for a synthetic glycan and 0.32   ng/mL for purified pneumococcal cell wall polysaccharide. DAMP also supported the immobilization of 29 structurally distinct carbohydrates with retained lectin recognition, as well as direct analysis of 13 native capsular polysaccharides for pneumococcal serotyping and vaccine-response profiling. This work establishes a practical and sensitive surface platform for high-fidelity carbohydrate immobilization and expands the utility of microarrays in polysaccharide research and glycan-based vaccine studies.