In vitro biocompatibility of novel biphasic calcium phosphate-mullite composites

In designing new calcium phosphate (CaP)-based composites, the improvement in physical properties (strength, toughness) without compromising the biocompatibility aspect is essential. In a recent study, it has been demonstrated that significant improvement in compressive strength as well as modest enhancement in toughness is achievable in biphasic calcium phosphate (BCP)-based composites with mullite addition (up to 30 wt%). Herein, we report the results of the in vitro cell adhesion, cell proliferation, alkaline phosphatase (ALP) activity, and osteocalcin (OC) production for a series of BCP-mullite (up to 30 wt%) composites. Mouse fibroblast (L929) cell lines were used to examine in vitro cell adhesion and cell proliferation; while osteoblast-like (osteosarcoma, MG63) cells were used for in vitro osteoblastic function study by ALP and OC expression. Much emphasis has been provided to discuss the cell viability and proliferation as well as osteoblastic differentiation marker on the investigated biocomposites in relation to the characteristics of the phase assemblage. On the basis of various observations using multiple biochemical assays, it has been suggested that BCP-mullite composites would be a candidate material for orthopedic applications.