Design and in vitro assessment of curcumin-eluting bilayer nanofiber coatings for improved endothelialization and blood compatibility of vascular stents

Cardiovascular stent implantation remains a widely used intervention, yet its long-term success is often limited by thrombus formation, oxidative stress, and inadequate endothelialization. To address these challenges, a novel bilayer poly(lactic acid)/hyaluronic acid (PLA/HA) curcumin-eluting nanofiber coating was designed and fabricated, engineered to improve the biological performance of vascular stents. The physicochemical properties, wettability, and water absorption were characterized, while curcumin loading efficiency, degradation behavior, and antioxidant activity were assessed to validate the functional performance. Hemocompatibility was investigated to examine blood interactions and cytocompatibility was evaluated using L929 and HUVEC cell lines to verify cellular responses relevant to vascular healing. Anti-thrombotic activity was determined by monitoring hemoglobin release as an indicator of clot formation. The results showed that curcumin incorporation enhanced hydrophilicity and significantly increased water absorption capacity. Curcumin was efficiently loaded in all groups and showing minimal degradation (<1%) over 28 days. Human umbilical vein endothelial cells (HUVECs) displayed high viability and adherence to bilayer coatings, supported by fluorescence staining, confirming the favorable topography and biochemical cues. A significant reduction in ROS levels demonstrated improved antioxidant efficacy. Both curcumin-blended and curcumin-free PLA/HA nanofiber coatings exhibited excellent hemocompatibility, with hemolysis below 0.5%. Anti-thrombotic assays of curcumin-blended stents showed stable performance under simulated in-practice conditions. In conclusion, curcumin-blended PLA/HA bilayer nanofiber coatings provide a multifunctional platform that enhances antioxidant protection, blood compatibility, and anti-thrombotic activity while supporting endothelialization, underscoring their potential as advanced coatings for cardiovascular stents.