Excellent Antimicrobial Activity of Fe3O4/SiO2/Ag Nanocomposites

In this study, a new antimicrobial agent was developed through a synthesis of Fe 3 O 4 /SiO 2 /Ag double nanocomposites using the sol–gel method. The prepared samples were characterized using XRD, SEM, FTIR, UV-Vis, VSM, and antibacterial test. The data analysis results for the Fe 3 O 4 /SiO 2 /Ag composites showed that Fe 3 O 4 , SiO 2 , and Ag constructed respective spinel cubic, orthorhombic, and amorphous structures in nanometric size. The saturation magnetization of Fe 3 O 4 /SiO 2 /Ag nanocomposites decreased due to the increase in the Ag content. Interestingly, the Fe 3 O 4 /SiO 2 /Ag nanocomposites presented excellent microbial activity. Ag deposition on the Fe 3 O 4 /SiO 2 surface enhanced the antimicrobial activity of nanocomposites because Ag oxidized to Ag[Formula: see text] ion to produce a toxic effect in the cells of microorganisms. Furthermore, the Ag[Formula: see text] ion created the –S–Ag bond chain and deactivated the microorganism cells. Furthermore, surface plasmon resonance of Ag had an impact on the formation of photo-induced electrons, which produced superoxide radical anions, [Formula: see text] generating a collapsing force that causes the death of microorganisms.