Characteristics and Osteoconductivity of Bone Composite Scaffolds Made of Thai Silk Fibroin, Gelatin and Inorganic Compounds: A Comparative Study of β‐Tricalcium Phosphate and Hydroxyapatite

Abstract

We developed the composite scaffolds made of Thai silk fibroin, gelatin, and inorganic compounds e.g. b-tricalcium phosphate (b-TCP) and hydroxyapatite (HA). The organic component of Thai silk fibroin/gelatin (50/50) was mixed with the inorganic b -TCP or HA at different mixing ratios. It was found that all scaffolds possessed porous structure with uniform distribution of b-TCP and HA (pore size $56-150 mm, porosity $87-94%). The Thai silk fibroin/gelatin scaffolds incorporating b-TCP or HA showed higher compressive modulus but lower water absorption ability than the pure protein scaffolds. Human periosteum-derived stem cells were isolated and cultured in the scaffold under osteogenic differentiation induction. The cells showed the greater ability of osteogenic differentiation when cultured in the Thai silk fibroin/gelatin scaffolds incorporating b-TCP, comparing with those of the pure protein scaffolds and the scaffolds incorporating HA, as confirmed by alkaline phosphatase activity and calcium production. The scaffolds incorporating b-TCP also supported cell spreading and deposition of calcium phosphate nodules. The promoted osteogenic differentiation of human periosteum-derived stem cells could be explained by the bioresorbable property and the high osteoinductive potential of b-TCP itself. Therefore, the Thai silk fibroin/gelatin (50/50) scaffolds incorporating b-TCP would be novel candidates for bone tissue engineering applications.