Fabrication of strontium and simvastatin loaded hydroxyapatite microspheres by one-step approach

Abstract The development of multi-functional strontium (Sr) and simvastatin (SIM) loaded biomaterials to promote angiogenesis and osteogenesis is a promising therapeutic strategy. In order to overcome the complex synthesis process, low drug loading and burst release of drug-loaded biomaterials, in this study, we developed a microwave-assisted hydrothermal one-step approach to prepare Sr- and SIM-loaded hydroxyapatite microspheres for achieving long-term sustained-release of Sr and SIM. The developed one-step preparation method can maintain the chemical structure of simvastatin, and the drug loading rate of simvastatin can reach more than 30 wt%. The prepared double-loaded hydroxyapatite microspheres could sustainable release Sr and SIM for more than 35 days. The prepared hydroxyapatite microspheres containing Sr and SIM have a good application prospect in promoting bone formation. This simple and feasible one-step method can also provide reference for the preparation of other drug-loading microspheres.