Hydroxyapatite/iron oxide nanocomposite prepared by high energy ball milling

Nanocomposites (HAp/iron oxide), made of hydroxyapatite (HAp) and ferrimagnetic iron oxide, were synthesized by high-energy ball milling a mixture consisting of iron oxide nanoparticles and the starting materials used for the HAp synthesis: calcium hydrogen phosphate anhydrous (CaHPO4), and calcium hydroxide (Ca(OH)(2)). Two HAp/iron oxide samples with the magnetic phase content of 12 and 30 wt. % were prepared and their microstructure, morphology and magnetic properties were analysed by X-ray diffraction and transmission electron microscopy. Furthermore, the measurement of particle size distribution was performed by laser scattering, and temperature/field dependence on magnetization was determined. X-ray diffraction data confirmed the formation of two phased samples (HAp and spinel iron oxide) without the presence of any other parasite phase. The shape of particles was nearly spherical in both samples, ranging from only a few to several tens of nanometres in diameter These particles formed agglomerates with the most common value of the number-based particle size distribution of 380 and 310 run for the sample with 12 and 30 wt.% of iron oxide, respectively. Magnetization data showed that both HAp/iron oxide composites had superparamagnetic behaviour at room temperature.