Magnetic and inductive heating properties of Fe3O4/polyethylene glycol composite nanoparticles with core–shell structure

The magnetite (Fe3O4) nanoparticles were prepared by coprecipitation of Fe3+ and Fe2+ using ammonium hydroxide (NH4OH) as a precipitating agent. The Fe3O4/polyethylene glycol (PEG) magnetic composite nanoparticles with a core–shell structure with a diameter of 10–40 nm were prepared by two step additions of the primary and the secondary surfactants, respectively. The inductive heat property of Fe3O4/PEG composite nanoparticles in an alternating current (AC) magnetic field was investigated. The potential of Fe3O4/PEG nanoparticles was evaluated for localized hyperthermia treatment of cancers. The saturation magnetization, Ms, and coercivity, Hc, are 67.06 emu g−1 and 7 Oe for Fe3O4 nanoparticles and 64.11 emu g−1 and 14 Oe for Fe3O4/PEG composite nanoparticles, respectively. Exposed in the AC magnetic field for 100 s, the temperatures of physiological saline suspensions containing Fe3O4 nanoparticles or Fe3O4/PEG composite nanoparticles are 89.2 °C and 72.2 °C, respectively. The Fe3O4/PEG composite nanoparticles will be useful as good thermoseeds for localized hyperthermia treatment of cancers.