Magnetic properties of bioactive glass-ceramics containing nanocrystalline zinc ferrite

Glass-ceramics with finely dispersed zinc ferrite (ZnFe2O4) nanocrystallites were obtained by heat treatment of x(ZnO, Fe2O3)(65-x)SiO(2)20( CaO, P2O5)15Na(2)O (6 <= x <= 21 mole%) glasses. X-ray diffraction patterns of the glass-ceramic samples revealed the presence of calcium sodium phosphate [NaCaPO4] and zinc ferrite [ZnFe2O4] as major crystalline phases. Zinc ferrite present in nanocrystalline form contributes to the magnetic properties of the glass-ceramic samples. Magnetic hysteresis cycles of the glass-ceramic samples were obtained with applied magnetic field sweeps of +/- 20 kOe and +/- 500 Oe, in order to evaluate the potential of these glass-ceramics for hyperthermia treatment of cancer. The evolution of magnetic properties in these samples, viz., from a partially paramagnetic to fully ferrimagnetic nature has been explored using magnetometry and X-ray diffraction studies. (C) 2010 Elsevier B.V. All rights reserved.