Efficiency of Heating Magnetite Nanoparticles with Different Surface Morphologies for the Purpose of Magnetic Hyperthermia

The magnetic and hyperthermia characteristics and the efficiency of heating (in an alternating magnetic field) magnetite nanoparticles with different surface morphologies are investigated. Spherical, cubic and elongated nanoparticles are synthesized by the solvothermal method using various precursors and stabilizers. The physical-chemical and hyperthermia characteristics of the obtained nanoparticles are studied by transmission electron microscopy, X-ray diffraction, vibration magnetometry, and magnetic hyperthermia. The average sizes of the spherical, cubic, and elongated nanoparticles are 18.5, 51.6, and 34.7 nm according to X-ray diffraction data and 23, 51.6, and 46.5 x 7.3 nm according to transmission electron microscopy data, respectively. The saturation magnetization varies from 51.5 emu/g for the spherical nanoparticles up to 84 emu/g for the cubic nanoparticles; the coercive force varies from 7.8 to 52.5 Oe, respectively. The hyperthermia characteristics of magnetite nanoparticles of different morphology are determined; the intrinsic loss power is found to be ILP = 2.72 nH m(2)/kg for the cubic nanoparticles and 1.54 nH m(2)/kg for the spherical ones. The obtained magnetic nanoparticles of magnetite of different morphologies can be considered as potential candidates for heat mediators for local magnetic hyperthermia.