Synthesis of Magnetic Novel Hybrid Nanocomposite (Fe3O4@SiO2/Activated Carbon( by a Green Method and Evaluation of Its Antibacterial Potential

Inorganic antibacterial nanoagents have more advantages compared to popularly organic agents due to chemical stability, thermal resistance, immunity, and long-term activity. In this study, a magnetically hybrid nanocomposite was prepared from the Nigella sativa oil waste as an organic matrix in a green approach. The homogeneous distribution of core-shell Fe3O4@SiO2 nanoparticles on the activated carbon surface was carried out with a simple chemical method. Characterization of the synthesized nanocomposite was performed by different analysis techniques such as scanning electron microscopy–energy dispersive spectroscopy, scanning electron microscopy, X-ray diffraction, and Brunauer-Emmett-Teller surface area analysis. The antibacterial activities of the prepared nanoparticles against gram-positive and gram-negative bacteria were investigated and the minimum inhibitory concentration and the minimum bactericidal concentration values were compared to imipenem as a standard antibiotic. The effects of temperature, time, and the ratio of the activated carbon to Fe3O4@SiO2 on the MIC and MBC values of the prepared nanocomposites were investigated. The obtained results reveal the substantial role of all of these parameters in the gram-positive antibacterial potential, especially for S. agalactiae bacteria. The results show that the new proposed nanocomposite could be an alternative for an effective filter against gram-positive bacteria alongside having magnetic properties.