Magnetic Nanorings for Biomedical Applications

In this work we investigate the characteristics and feasibility of a new class of magnetic particles that are optimized for possible biological applications as magnetic hyperthermia. These new nanostructures have the nanoring shape, being composed of iron oxides (magnetite or hematite). Such morphology gives the nanoparticles a peculiar magnetic behavior due to their magnetic vortex state. The iron oxide nanorings were obtained using hydrothermal synthesis. X-ray Diffraction confirmed the existence of the desired crystal structure and Scanning Electron Microscopy shows that the magnetite particles had nanometric dimensions with annular morphology (diameter ~250 nm). The nanorings also show intensified magnetic properties and a transition to a vortex state. This study showed that it is possible to obtain magnetic nanorings with properties that can be used in nanotechnological applications (mainly biotechnological ones aimed at the treatment and diagnosis of cancer), in large quantities in a simple synthesis route.