Synthesis of baghdadite using modified sol–gel route and investigation of its properties for bone treatment applications

The requirement for biomaterials with superior properties, used in bone treatment applications, is inevitable due to escalated bone tissue defects. Baghdadite (BAG) is a calcium silicate that benefits from the presence of zirconium (Zr) in its structure and has attracted huge attention in recent years. In this study, a modified sol–gel route was proposed to synthesize BAG by dissolving Zr precursor separately and using optimum amounts of solvent and chelating agent. Due to thermal gravimetric analysis and differential thermal analysis (TGA–DTA), X-ray diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR) results, the BAG nanoparticles were successfully synthesized using this modified approach for the first time, and they were comprehensively characterized in terms of physicochemical, mechanical, and biological properties. During synthesis, a transparent sol without any insoluble Ca or Zr precursors and/or no premature gelation was observed, unlike samples that we produced using the conventional sol–gel method in the literature. The crystalline BAG nanoparticles with semi-spherical shapes demonstrated ~ 20% weight loss after 28 days during the biodegradability test, extensive bioactivity, and enhanced mechanical strength (~4 MPa). Moreover, BAG powder was biocompatible with no cytotoxic effect and osteoinductive in the absence of an osteogenic medium. We believe that the synthesized BAG nanoparticles through this modified sol–gel route could serve as a promising biomaterial for cancellous bone defect treatment applications.