The influence of cross-linking methods on the mechanical and biocompatible properties of vascular scaffold

Electrospun scaffolds fabricated from poly(epsilon-caprolactone) (PCL)/collagen composite are promising candidates for vascular graft applications. In order to improve the biocompatibility and mechanical strength of PCL/collagen scaffolds, two different cross-linking methods were applied and compared: (1) 2.5% glutaraldehyde (GA) vapor cross-linking for 6 h and (2) genipin (GN) cross-linking for 3 days in 70% ethanol. Scaffolds cross-linked with GN demonstrated higher cross-linking degree, collagen content, tensile strength and a similar stiffness compared with GA cross-linked scaffolds. Scaffolds cross-linked with GA and GN both supported endothelial and smooth muscle cell attachment and growth. However, cells seeded on GN cross-linked scaffolds displayed a faster growth rate and deeper penetration into the scaffolds than those cross-linked with GA. These data suggest that the use of GN to cross-link PCL/collagen scaffolds may enhance the cellularization of vascular scaffolds resulting in a more rapid development of integrated functional vessels in vivo.