Bilayer porous scaffold based on poly-(ɛ-caprolactone) nanofibrous membrane and gelatin sponge for favoring cell proliferation

Electrospun poly-(ɛ-caprolactone) (PCL) nanofibers has been widely used in the medical prosthesis. However, poor hydrophilicity and the lack of natural recognition sites for covalent cell-recognition signal molecules to promote cell attachment have limited its utility as tissue scaffolds. In this study, Bilayer porous scaffolds based on PCL electrospun membranes and gelatin (GE) sponges were fabricated through soft hydrolysis of PCL electrospun followed by grafting gelatin onto the fiber surface, through crosslinking and freeze drying treatment of additional gelatin coat and grafted gelatin surface. GE sponges were stably anchored on PCL membrane surface with the aid of grafted GE molecules. The morphologies of bilayer porous scaffolds were observed through SEM. The contact angle of the scaffolds was 0°, the mechanical properties of scaffolds were measured by tensile test, Youngʹs moduli of PCL scaffolds before and after hydrolysis are 66–77.3 MPa and 62.3–75.4 MPa, respectively. Thus, the bilayer porous scaffolds showed excellent hydrophilic surface and desirable mechanical strength due to the soft hydrolysis and GE coat. The cell culture results showed that the adipose derived mesenchymal stem cells did more favor to adhere and grow on the bilayer porous scaffolds than on PCL electrospun membranes. The better cell affinity of the final bilayer scaffolds not only attributed to the surface chemistry but also the introduction of bilayer porous structure.