Preparation and bioactivity of biodegradable β-tricalcium phosphate / calcium carbonate / phosphate bioactive glass composite porous ceramic

Abstract

Background: At present, scaffold biomaterials with great biodegradation and biocompatibility are attracting more and more attention. Phosphate bioactive glass (PBG) without Si has been prepared successfully, with a glass transition temperature below 600°C. Calcium carbonate (CC)-based bioceramics with PBG as binder were sintered rapidly at a lower temperature. β-Tricalcium phosphate (β-TCP) has always been used to synthesize clinical ceramics due to its wonderful biocompatibility. Here, we combined the advantages of these raw materials to obtain a novel β-TCP/CC/PBG composite porous ceramic. Method: The preparation process of β-TCP/CC/PBG was optimized by controlling PBG content, NaCl ratio, sintering temperature, and holding time. Ceramic biodegradability was evaluated by soaking in a Tris-HCl buffer in vitro, and biocompatibility of the new material was indicated using CCK-8 tests and a live/dead fluorescence assay. Results: The best mechanical properties of β-TCP/CC/PBG composite porous ceramics were obtained with a PBG content of 60%, at which point the proportion of NaCl exerted the most significant influence on the density, porosity, and mechanical properties of the materials. The weight loss rate of the composite ceramics was 11.30%, which was much higher than that of β-TCP (1.41%) and hydroxyapatite (0.83%) ceramics. CCK-8 test and live/dead fluorescence assay indicated that the composite porous ceramics showed a biocompatibility similar to that of β-TCP ceramics. Conclusion: β-TCP/CC/PBG composite porous ceramics have potential applications in bone regeneration. It is hoped that the novel biomaterial developed in this study will prove useful for the repair of bone defects.