Hydroxyapatite-Hardystonite nanocomposite scaffolds prepared by the replacing the polyurethane polymeric sponge technique for tissue engineering applications

Objective (s): Silicate bioceramics containing Zn and Ca like hardystonite (Hr) with chemical formula Ca2ZnSi2O7 has attracted the attention of researchers in biomedical field due to its remarkable biological and mechanical properties. The new generation of bioceramics can applied in bone tissue engineering to substitute with infected bone. However, these zirconium-silicate bioceramics have proper features; they can be used as additive with calcium phosphates (CaPs) like hydroxyapatite (HA). These composite may enhance the weak properties of pure HA powders. Materials and Methods: In the current study, the Hr powder with sol-gel method was synthesized. Then, hydroxyapatite-hardystonite (HA/Hr) scaffolds with various amount of Hr in HA (0, 5, 10, and 15 wt. % )  were prepared by the replacing the polyurethane polymeric sponge technique. Then, the ceramic scaffolds were sintered at 1150ºC for 3 hours. The result of the scaffold nanocomposite specimens were tested for compressive strength and bioactivity behaviour. The phase and morphology of the specimens were analysis with X-ray Diffraction (XRD) and Scan Electron Microscope (SEM) techniques. Results: The bioactivity, sinterability and compressive strength (CS) properties of HA-Hr scaffold nanocomposite has been developed by addition of 15 wt. % Hr in HA matrix. The results showed the scaffold nanocomposite containing 15 wt. % Hr have the highest value of CS which is equal 1.21 MPa. Our data indicate that Hr ceramics possess proper mechanical properties as compared to pure HA, and may possess good biocompatibility in biological analysis. Conclusion: The study indicates that scaffold containing 10 wt. % Hr had proper bioactivity behaviour which leads the scaffolds surface to form bone-like apatite on the surface of scaffolds.