Fabrication of polycaprolactone tubular scaffolds with an orthogonal-bilayer structure for smooth muscle cells

In this study, we used electrospinning to prepare a bilayered polycaprolactone (PCL) tubular graft consisting of an internal layer comprising axial nanofibers and an external layer comprising circumferentially aligned nanofibers. Subsequently, the surfaces of the electrospun PCL tubular scaffolds were modified with 1,6-diaminohexane to introduce amino groups and were then chemically conjugated with gelatin (Gel). The amino groups and Gel were successfully immobilized on the PCL scaffolds according to a ninhydrin assay, attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopic analysis and contact angle analysis. Additionally, vascular smooth muscle cells (vSMCs, A7r5) were cultured on random and aligned Gel-PCL scaffolds to evaluate the effects of fiber orientation on cell behavior. The results of immunofluorescence analysis showed that vSMCs on the aligned Gel-PCL scaffolds exhibited a pro-contractile phenotype.