Physicochemical evaluation of Chitosan-gelatin-Hydroxyapatite composite scaffold prepared by freez drying

Bone tissue engineering is an alternative strategy to generate bone utilizing a combination of biomaterials and cells. Bioactive porous three-dimensional scaffolds play important role in promotion of cellular proliferation and differentiation in tissue regeneration. In this study, in order to preparing of bone tissue engineering scaffold with good biocompatibility,bioactivity and physicochemical properties; we constructed porous three-dimensional chitosan-gelatin/hydroxyapatite and chitosan-gelatin/β-TCP composite scaffolds containing different amounts (0, 10, and 20wt.%) of gelatin through freeze-drying method. A novel bioactive ceramic/chitosan-gelatin network (HA- β-TCP /CS-Gel) was prepared as a three-dimensional biomimetic scaffold by freeze-drying method. Composite scaffolds of chitosan (CS)–gelatin (CG) with Hydroxyapatite and β-TCP were prepared by freez-drying of chitosan and gelatin(0%-10%-20%)- HA and β-TCP. The prepared Chitosan-gelatin/ceramic composite scaffolds were characterized using SEM and FTIR studies. The effect of gelatin and β-TCP in the scaffold matrix were evaluated in terms of scaffold properties.. In addition swelling ratio, porosity measurement of the composite scaffolds were studied. Our SEM results showed macroporous internal morphology in the scaffold with pore size ranging from 96to 206μm. Swelling behavior of the interconnected network showed the increasing of porosity with rising gelatin. The porosity decreased with increasing concentration of gelatin from 10% to 20%. Also due to the higher solubility rate of β-TCP, the porosity, pore size and swelling rate with the addition of β-TCP increased. FTIR studies showed the strong interaction between ceramic and chitosan-gelatin network. The results indicated that Chitosan-gel- HA scaffolds, fully interconnected with high porosity structure, thoroughly open pores and tailored pore size which prepared by freez-drying method is very similsr to bone structure, therefore it is suitable scaffold for bone tissue engineering.