La/Sr Dual-Substituted Hydroxyapatite Nanoparticles as Bone Substitutes: Synthesis, Characterization, Bioactivity and Cytocompatibility.

The present study aims to synthesize biocompatible and bioactive lanthanum (La)/strontium (Sr) dual ion doped hydroxyapatite (HA) nanomaterials by sol-gel method. The discrete substitution of La and Sr in pure HA enhances the osteoconductivity. The co-substitution of various La concentrations (0.03, 0.06 and 0.1 M) regulates the physical and properties. The study also investigates the effect of La/Sr substituents on the crystalline property, microstructure, photoluminescence and bioactivity of HA samples. La/Sr co-substitution decreases the crystallite size of HA without any significant distortion of the crystal structure. In addition, the dual ions doping influences nanoparticles morphology by reducing the particle size from 75 to 20 nm. The bioactivity tests for the La/Sr co-substituted HA confirm the osteoconductive boneapatite generating capacity. Bactericidal tests against and stains show better resistivity of La/Sr-HA samples. To authenticate the biocompatibility and antimicrobial activity of the synthesized La/Sr dual doped HA nanoparticles for bone implant applications, different tests like cell viability and toxicity were conducted using human lung A549 cells.