synthesis of coated iron oxide nanoparticles and feasibility study of their use in magnetic hyperthermia

The unique properties of magnetic nanoparticles have made them useful and important particles for use in various fields, especially in heat-based applications. this research presents a hopeful facet of magnetic hyperthermia by superparamagnetic fe3o4/alumina nanoparticles. we synthesized fe3o4/alumina nanoparticles of different sizes by sonochemical method and evaluated their ability to generate heat. we found by characterizations with field emission scanning electron microscopy (fe-sem), x-ray diffraction technique (xrd), and transmission electron microscopy (tem) the samples to be of spherical shapes and spinel structure whose diameter could be controlled in the range from 15 to 25 nm. the magnetic behavior of the samples determined using a vibration sample magnetometer (vsm) showed hysteresis loops with a coercivity (hc) close to zero, suggesting superparamagnetic behavior at room temperature. the saturation magnetization (ms) for sample 3 after synthesis is 23 emu/g. we also investigated the potential of the samples for magnetic hyperthermia using alternating magnetic fields at various frequencies. samples 1, 2, and 3 achieved heat production rates of 0.22 °c/min, 0.41 °c/min, and 0.62 °c/min respectively under an alternating magnetic field with an amplitude of 120 oe and a frequency of 250 khz.