Green Capping Agents and Digestive Ripening for Size Control of Magnetite for Magnetic Fluid Hyperthermia

Magnetite is the most recognized iron oxide candidate used for various biological applications. This work is a complete study that addresses the synthesis of magnetic nanoparticles and investigates the feasibility of using green tea and ascorbic acid as capping agents. Synthesis of magnetite by two wet chemical methods namely: coprecipitation and solvothermal methods. The samples were characterized using X-ray diffraction (XRD), transmission electron microscope (TEM), and vibrating sample magnetometer (VSM). The results reveal the impact of coating on the size and morphology of the particles. The study also proves that autoclaving the samples prepared by coprecipitation results in smaller particle size and narrower size distribution due to digestive ripening. In addition, a novel and facile methodology for coating magnetite with polyethylene glycol is presented. The potential of the particles to be used for magnetic fluid hyperthermia is assessed by measuring the specific absorption rate (SAR) of the samples. The results show that all the prepared magnetite samples showed a promising capacity to be used as magnetic fluid hyperthermia agents.