Sustained H2S‑Releasing Glycocalyx-MimeticCoatings on Polydimethylsiloxane Surfaces for Balanced Anticoagulationand Vascular Cell Selectivity

Thrombosis and intimal hyperplasia are two major challenges leading to the failure of blood-contacting materials. To address these challenges, a hydrogen sulfide (H₂S)-releasing glycocalyx-mimetic “core-shell” composite coating was constructed on polydimethylsiloxane (PDMS). The “core” comprised a PDMS matrix embedded with an H₂S donor for sustained release. Following polydopamine/polyethylenimine interlayer deposition, a glycocalyx-mimetic “shell” of poly(sodium 4-vinylbenzenesulfonate-co-oligo(ethylene glycol) methyl ether methacrylate) was covalently grafted. The optimized coating, featuring a shell polymerized from 30 mol % sodium 4-vinylbenzenesulfonate and 70 mol % oligo(ethylene glycol) methyl ether methacrylate (designated as AT-PP2), achieved controlled 7-day H₂S release and maintained 15-day physiological stability. The synergy between released H₂S and the biomimetic shell conferred exceptional hemocompatibility and cell selectivity. Compared to unmodified PDMS, AT-PP2 reduced platelet adhesion by ∼93%, prolonged activated partial thromboplastin time and thrombin time by ∼67% and ∼119%, respectively, and enabled precise bidirectional regulationpromoting endothelial cell adhesion while inhibiting smooth muscle cell hyperplasia. This “Active Defense” anticoagulation with “Dynamic Modulation” regeneration strategy offers a promising endothelial-mimetic platform for next-generation blood-contacting materials.