A Simple and Reliable Synthesis of Superparamagnetic Magnetite Nanoparticles by Thermal Decomposition of Fe(acac)3

Magnetic nanoparticles have been largely proposed as means of technological tools due to its value in different fields, especially in biomedicine. Herein, we present a robust, highly reproducible and low-cost method to obtain superparamagnetic magnetite nanoparticles (MNP-II) of about 15 +/- 5 nm diameter by thermal decomposition of [Fe(acac)(3)] in a one-pot, two-step method. In the first step, magnetite nanoparticles (MNP-I) of lower size, 9 +/- 4 nm, with a saturation magnetization (MS) of 65 emu/g and a coercive field (Hc) of 1 Oe are obtained. In the second step, those particles MNP-I act as seeds for the final MNP-II which present a saturation magnetization of 70 emu/g and a coercive field of 12 Oe.