Synthesis, characterization and antibacterial effect of new magnetically core–shell nanocomposites

Abstract

A new magnetically responsive three-component nanocomposite consisting of NiFe₂O₄, Poly Acrylonitrile Co Maleic Anhydride (PAMA) and nanosilver was synthesized and characterized and then its antibacterial activities were tested. For the preparation of NiFe₂O₄@Ag, NiFe₂O₄ was coated by Ag and for the synthesis of NiFe₂O₄@PAMA@Ag, NiFe₂O₄ was first covered by PAMA and then silver nanoparticles were immobilized on the surface of the PAMA shell. The nanocomposites were studied using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM). The antibacterial activity of the synthesized nanocomposite against some gram positive and gram negative bacteria was studied and compared with that of naked NiFe₂O₄, NiFe₂O₄@Ag and NiFe₂O₄@PAMA. The NiFe₂O₄@PAMA@Ag had better antibacterial activity and could be readily isolated from the aqueous solution via magnetic decantation, thereby avoiding the contamination of the environment.