Magnetic drug-loaded osteoinductive Fe 3 O 4 /CaCO 3 hybrid microspheres system: efficient for sustained release of antibiotics

A novel magnetic drug-loaded osteoinductive Fe 3 O 4 /CaCO 3 hybrid microspheres system (MDHMs) with excellent drug delivery property has been fabricated by a modified coprecipitation method. The MDHMs are uniform vaterite microspheres with well-defined mesoporous nanostructures. The formation of vaterite is based on the templating effect of casein micelles, which is promising in bone tissue engineering. Cyclodextrins (CDs) increase the porosity of the microspheres with a pore size of about 7.3 nm and a surface area of about 50.73 m 2 g −1 . The mesoporous structure gives the MDHMs great drug loading efficiency of about 80.75–88.74% and the minocycline-loaded MDHMs display a sustained drug release property (about 95% in 5 d). Moreover, the MDHMs also possess stable magnetic property with a saturation magnetization of about 4.41 emu g −1 and a remarkable magnetism-responsive behavior. These results demonstrate that with superior drug delivery property, osteoinductive potential and magnetic property, the MDHMs have a great potential in the treatment of peri-implantitis.