In-vitro and in-vivo studies of PLA/PCL/gelatin composite scaffold containing ascorbic acid for bone regeneration

Bone cells require solid support similar to the extracellular matrix networks for repairing damaged areas of the bone. Selecting materials and manufacturing process of scaffold is a fundamental challenge in tissue engineering which are always investigated. The current study is attempted to fabricate a scaffold that provides appropriate properties for bone tissue engineering. Due to the positive effect of ascorbic acid on bone healing, a highly porous 3-D Polylactic acid/Polycaprolactone/Gelatin (PLA/PCL/Gel) scaffold containing different concentration of ascorbic acid were prepared by combining electrospinning and freeze-drying techniques. A series of in vitro and in vivo studies such as assessing surface morphology, FTIR, porosity, compressive strength, water contact angle, degradation rate, releasing profile, PH alteration, hemolysis, alizarin red staining, cell proliferation, and cell attachment were performed to evaluate mechanical and biological properties of the fabricated scaffold. For further investigation, a rat calvaria defect model was used to evaluate its effect on bone regeneration. The results showed that scaffolds had porosity of about 80% which is sufficient for cell penetration and migration. Moreover, by adding ascorbic acid, compress strength and contact angle decreased while the scaffold degradation increased. All of the groups have in vitro and in vivo studies indicated that among different groups, PCL/PLA/Gel/AA5%-treated group had better effect on cell proliferation and bone healing. The obtained results indicate that prepared scaffolds play a positive role in osteogenesis and growth pattern of culture.