Chitosan/calcium phosphate composites scaffolds prepared by membrane diffusion process

Abstract

Hydroxyapatite (Ca₁₀(PO₄)6(OH)₂, HAp) and Dicalcium phosphate dihydrate (CaHPO₄.H₂O, DCPD) were homogeneously hybridized into chitosan solution by membrane diffusion process. The three-dimensional scaffolds were obtained by freeze-drying process.The organic and inorganic contents of scaffold were determined by using thermogravimetry analysis (TGA). The surface morphology of the scaffold and characteristic of calcium phosphate were investigated by scanning electron microscope (SEM), energy dispersive X-ray spectrometer (EDX), and X-ray diffraction (XRD), respectively. Compressive modulus was also determined by dynamic mechanical analysis (DMA). The hybridized inorganic content ranges from 35-45%.Both chitosan/HAp and chitosan/DCPD scaffolds showed interconnected porous structure. The calcium to phosphorus ratios of chitosan/calcium phosphate composite scaffolds obtaining from SEM-EDX followed to the theoretical ratios of HAp and DCPC for chitosan/HAp composite and chitosan/DCPD composite, respectively. XRD pattern showed that the products of composite scaffold were HAp and DCPD. These results suggest that calcium phosphate can be hybridized into chitosan solution through membrane diffusion process, followed by forming the porous scaffolds by freeze-drying. Therefore, as prepared porous chitosan/calcium phosphate composite scaffolds can be considered as potential materials for tissue engineering.