Cytotoxicity of thermoresponsive core/shell Ni x Co1− x Fe2O4/PEG nanoparticles synthesized by the sol–gel method

Abstract

Abstract These days, magnetic nanoparticles (MNPs), especially cobalt ferrite MNPs, have attracted the attention of many scientists in many applications, e.g. cancer treatment, due to their good magnetic properties. In this study, firstly the Ni x Co1−x Fe2O4 MNPs (x = 0, 0.25, 0.5, and 0.75) were prepared through the sol–gel technique. The resulting particles were then coated with polyethylene glycol (PEG) polymer to obtain a core/shell structure. The x-ray diffraction and Fourier-transform infrared spectroscopy results illustrated that CoFe2O4 MNPs were successfully synthesized. Vibrating-sample magnetometer and (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bro-mide) assay results illustrated that the Ni0.5Co0.5Fe2O4 sample had the best saturation magnetization (71.68 emu g−1) and coercivity (∼500 Oe) values. Subsequently, the appropriate amount of PEG was found to be 15% wt/vol. The toxicity test showed that a concentration of 100 μg ml−1 of particles kept 96% of the cells alive. The particle size of the core/shelled MNPs was obtained to be ∼25 nm via a transmission electron microscopy image. Finally, it was observed that the Ni0.5Co0.5Fe2O4 sample coated with 15% wt/vol. PEG can be potentially used for hyperthermia.