Preparation and characterization of Sr-hardystonite (Sr2ZnSi2O7) for bone repair applications

In this work, the potential of Sr-hardystonite (Sr₂ZnSi₂O₇) ceramics for biomedical use was first detected. First, pure Sr₂ZnSi₂O₇ powders were successfully synthesized by sol-gel method, and then Sr₂ZnSi₂O₇ ceramics were prepared by sintering the powder compacts. The mechanical test showed that the bending strength and Young's modulus of Sr₂ZnSi₂O₇ ceramics could reach 82 MPa and 44 GPa, respectively, which were close to the values for human cortical bone. Degradation test in Tris-HCl buffer solution showed that Sr₂ZnSi₂O₇ ceramics had a low degradation rate with less than 3% weight loss after soaking for 28 days. Furthermore, the in vitro biocompatibility of the ceramics was evaluated by rabbit bone marrow stem cells (rBMSCs) adhesion and proliferation assay. The results showed that the ceramics supported the cells adhesion and proliferation. Taken together, Sr₂ZnSi₂O₇ might be a potential candidate for preparation of bone implants.