XANES and EXAFS characterization of zinc-doped magnetite nanoparticles for hyperthermia applications

G. A. PASQUEVICH; S. STEWART; F. H. SÁNCHEZ; B. PIANCIOLA; P. MENDOZA ZÉLIS; M. B. FERNÁNDEZ VAN RAAP; S. JACOBO; J. APHESTEGUY

Activity Report 2010: LNLS ISNN1518-0204

Ministry of Science and Technology / Brazilian Association for Synchrotron Light Technology

Año: 2011; p. 200 - 202

Magnetic hyperthermia therapy appears as a promising technique for low invasive elimination of tumors, or as a way to improve the efficiency of chemo or radio therapy. Magnetite is one of the best candidates to be used in effective treatments, even though presents an undesirable high ordering temperature (TN ). Here we present a detailed study of zinc-doped magnetite in a search for better materials for hyperthermia applications. Mean sizes lower than 40 nm and compositions were envisaged to produce high specific loss power (SLP). To this end, Zn concentration was varied to optimize the saturation magnetization and lower the order temperature. To achieve a complete knowledge of their structural, microstructural and magnetic properties, an exhaustive characterization of the samples was performed with several techniques like XRD, Mössbauer Effect Spectroscopy (MES), magnetometry and XAS.