Fabrication of Fe3O4@Polydopamine@Bovine Serum Ablumin (BSA) and Fe3O4@Polydopamine-Ag Core—Shell Nanoparticles and Their Catalytic and Antibacterial Properties

The submicron-sized Fe3O4 particles were synthesized by solvothermal method. Then polydopamine (PDA) was used to modify the surface of Fe3O4 particles. And then the core—shell Fe3O4@PDA@BSA (single layer and multilayer) microspheres were prepared by the layer by layer self-assembly method (SAM). In addition, Ag nanospheres were grafted onto the surface of Fe3O4@PDA particles to obtain Fe3O4@PDA-Ag core—shell nanoparticles using silver mirror reaction. The morphology and component of the obtained core—shell particles were characterized by transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The biocompatibility of the microspheres was researched in vitro by MTT method and its magnetic properties were also evaluated. The results showed that the microsphere has excellent magnetic properties and good biological safety. Then the catalytic performance of Fe3O4@PDA-Ag microspheres for methylene blue (MB) was studied. And the antimicrobial properties of Fe3O4@PDA-Ag microspheres for Escherichia coli and Bacillus subtilis were also be discussed. The results indicated good catalytic properties and antibacterial properties.