Melt Electrospinning-Based Polycaprolactone Small-Diameter Artificial Blood Vessels: Integrated Design and Performance Evaluation of Process, Structure and Function

The development of small-diameter artificial blood vessels for the treatment of cardiovascular disease faces critical challenges, including mismatches in mechanical properties, poor cellular compatibility, and a high propensity for thrombosis. In this study, we fabricated polycaprolactone (PCL)-based small-diameter vascular scaffolds by melt electrospinning technology. By optimizing processing parameters, we successfully constructed a vascular framework with a hierarchical fibrous network. Biomimetic vascular scaffolds with three distinct architectures (star, triangle, and square) were systematically compared in terms of their performance. Further surface multifunctionalization was achieved using NaOH-induced hydrophilization, Ethyldimethylaminopropyl carbodiimide/N-hydroxy succinimide (EDC/NHS)-mediated heparin grafting, and coating with a rutin-loaded gelatin methacryloyl (GelMA) hydrogel. Analysis demonstrated that the optimized structure of stars met the mechanical requirements of human coronary arteries, exhibiting a fracture elongation of 929.8% and a Young’s modulus exceeding 1.5 MPa. The 0.1% rutin-loaded coating enabled sustained drug release with <6% mass loss over 6 days while maintaining high cell viability. Furthermore, heparinization significantly enhanced anticoagulant properties, with hemolysis rates <5%. Overall, we present an integrated “process-structure-function” strategy to successfully engineer small-diameter artificial blood vessels with favorable mechanical performance, biocompatibility, and in vitro anticoagulant properties, thereby providing a reliable material platform and technical route for the in-depth fundamental research and further developmental exploration of small-diameter vascular substitutes.