Fabrication of Fe 3 O 4 /Ag-TiO 2 magnetic nanocomposite for antibacterial applications

[摘要] Water pollution is a major cause of fatality in the less developed parts of the world. One of the major concerns in this regard is due to activities of both Gram-positive and Gram-negative bacteria. The Fe 3 O 4 /Ag-TiO 2 nanocomposite, stabilized in a matrix of TEOS–APTES, is prepared in this study via a facile chemical procedure as a potential magnetic antibacterial agent for treating pathogen-polluted aqueous media. The multifunctioning character of this nanocomposite provides photocatalytic effect of TiO 2 components combined with Ag nanoparticles (AgNPs), as well as separation capability by magnetic response of Fe 3 O 4 particles. To stabilize the nanocomposite formulation, a matrix of TEOS-APTES is employed as support to facilitate combination of Ag-TiO 2 nanoparticles with Fe 3 O 4 magnetic cores. When exposed to an external magnetic field, the undesirable release of Ag particles is prevented by the Fe 3 O 4 cores that enable the nanocomposite to be collected from the environment. The magnetic character of the nanocomposite was evidenced by VSM. The morphology of Ag-TiO 2 nanoparticles, the core–shell structure of Ag-TiO 2 /Fe 3 O 4 particles, the crystalline structure and hydrodynamic diameter of nanocomposite were investigated by FT-IR, FE-SEM, TEM, XRD and DLS analyses. The antibacterial activity of the samples was determined by agar disk diffusion. It was revealed that the Fe 3 O 4 /Ag-TiO 2 nanocomposite could produce a larger zone of inhibition than Ag + ions and Ag-TiO 2 , which could be related to the size distribution and synergistic antibacterial effects of Ag and TiO 2 components. The designed nanocomposite formulation could be considered as a promising candidate for antibacterial water treatment applications.

[学科分类] 计算机科学（综合）

[关键词] antibacterial activity;nanocomposites;nanomagnetics