Preparation of composite tubular grafts for vascular repair via electrospinning

A novel type of composite vascular graft was developed via electrospinning in the present investigation. Collagen and chitosan were blended to form the inner and outer layer. Poly(l-lactide-co-caprolactone) (P(LLA-CL)) was selected as a material for the middle layer of composite vascular graft. Both morphology and diameter of the composite grafts were studied by Scanning Electron Microscope (SEM). The results of mechanical tests showed that the composite scaffolds provided the whole grafts with better strength and flexibility compared with blended grafts, mainly due to the fact that the middle layer was P(LLA-CL). Cell viability studies with endothelial cells suggested a prompt adhesion and proliferation duo to the fact that the outer layer was collagen and chitosan. Confocal microscopy demonstrated that a monolayer of endothelial cells could be formed after 7 days of culture. The above results indicated that the composite fibrous scaffolds could be a good candidate for blood vessel repair by electrospinning method.