Approaches to Fabricating Multiple-Layered Vascular Scaffolds Using Hybrid Electrospinning and Thermally Induced Phase Separation Methods

Fabrication of small-diameter vascular scaffolds has been a challenge in recent years, especially scaffolds with multiple layers. In this study, two approaches were proposed to fabricate triple-layered vascular scaffolds based on the electrospinning method and the thermally induced phase separation (TIPS) method. It was found that the electrospun fibers had a compact fibrous structure that provided good mechanical properties. The porous TIPS layer had high porosity and pore interconnectivity to facilitate cell penetration; however, this structure alone could not ensure sufficient mechanical properties for surgical applications. The triple-layered scaffolds, which consisted of electrospun TPU, TIPS TPU, and electrospun PPC layers, showed the highest mechanical properties and best structure and dimensions for vascular graft applications. Preliminary endothelial cell culture results showed that the cells could attach to and proliferate on the inside surface of the scaffolds with >95% viability.