Silk Fiber as the Support and Reductant for the Facile Synthesis of Ag–Fe3O4 Nanocomposites and Its Antibacterial Properties

We report a facile and environmentally friendly approach to prepare Ag–Fe3O4–silk fiber nanocomposites. The Ag–Fe3O4–silk fiber acts as: (i) a biocompatible support for the silver nanoparticles; and (ii) a reducing agent for the silver ions. Neither additional reducing agents nor toxic organic solvents were used during the preparation process. The Ag–Fe3O4–silk fiber nanocomposites can be actuated by a small household magnet and have high antibacterial activities against both Escherichia coli and Staphylococcus aureus. These nanocomposites could be easily recycled without a decrease in their antibacterial activities due to the synergistic effects between the Ag NPs and Fe3O4 NPs with large amounts of active sites.