Surface bio-engineering of melt electrowritten tubular scaffolds via plasma immersion ion implantation (PIII)

This study developed a plasma immersion ion implantation (PIII) method to biofunctionalize melt electrowritten (MEW) polycaprolactone (PCL) tubular scaffolds for vascularized tissue engineering. PIII generated stable radical-rich surfaces enabling uniform covalent immobilization of vascular endothelial growth factor (VEGF) without altering scaffold architecture or mechanics. Surface characterization confirmed homogeneous nitrogen implantation, oxidation, and carbonization across the 3D structure, producing highly hydrophilic, endothelial cell-instructive scaffolds. VEGF-functionalized MEW tubes promoted ciGEnC endothelial monolayer formation and maturation comparable to conventional VEGF supplementation, validating the system as a scalable bioinstructive platform for organ-on-chip and regenerative applications.