Magnetic Hyperthermia Properties of Electrosynthesized Cobalt Ferrite Nanoparticles

Using the electrochemical route, cobalt ferrite nanoparticles (NPs) with two different sizes were synthesized and stabilized in water by coating with citric acid. The specific absorption rate (SAR) values of aqueous suspensions of magnetic nanoparticles with crystal sizes of 13 and 28 nm were investigated in the frequency range 32-101 kHz and up to 51 mT. SAR values were higher for the larger NPs and reached 133 W/g. Numerical simulations are used for a quantitative analysis of hyperthermia experiments and seem to indicate that the larger NPs are multidomain. Cytotoxicity analysis was also performed in HeLa tumor cells; a null cytotoxicity of these nanoparticles in cell tissues were obtained.