Fabrication and characterization of a porous composite scaffold based on gelatin and hydroxyapatite for bone tissue engineering

Gelatin is a natural protein derived from the organic constituent of bone (collagen type 1). Therefore its combination with the natural mineral constituent of bone (HA) is supposed to provide closer properties to the natural bone. In this study, porous scaffolds based on gelatin-hydroxyapatite composite were fabricated by solvent casting method. To increase the biocompatibility of the composite, its fabrication was carried out without using any organic solvent and the porosities of these scaffolds were obtained without using any porogen. The fabrication of porous scaffolds with 6 different compositions (0, 10, 20, 30, 40 and 50 wt% of HA in gelatin, respectively), was fallowed by characterizing and determinig their pore size, morphology, and bending modulus. Cell seeding procedure was carried out using mouse fibroblasts to evaluate the scaffolds' biocompatibility. The scaffolds exhibited pore size range from 50 to 200 micrometers with the good interconnectivity. The obtained bending moduli (above 35 GPa) were higher than those of any other biodegradable scaffolds such as SR-PGA and PLLA/HA that have been reported earlier in the literature. The experiments showed that not only the amount of porosity but also the interconnectivity of pores decreases with increasing HA content. It was also demonstrated that the addition of HA would increase the bending modulus. Cell seeding experiments showed appropriate cell attachments for all the samples.