Ferromagnetic Gd5Si4 Nanoparticles as T2 Contrast Agents for Magnetic Resonance Imaging

Room temperature ferromagnetic Gd 5 Si 4 nanoparticles were synthesized using arc-melting and high-energy ball milling. We demonstrate that these particles can be used as potential T2 contrast agents for magnetic resonance imaging (MRI). The ball-milled Gd 5 Si 4 nanostructured material shows a ferromagnetic-to-paramagnetic transition at 320 K, revealing long-range magnetic order of the Gd 5 Si 4 phase. Echo time was measured in a 7 T magnetic resonance imaging system and shows significant reduction compared to that reported for superparamagnetic iron oxide nanoparticles. These results show the potential of Gd 5 Si 4 ferromagnetic nanoparticles as T2 contrast agents for MRI.