Gd-Si Oxide Nanoparticles as Contrast Agents in Magnetic Resonance Imaging.

We describe the synthesis, characterization and application as contrast agents in magnetic resonance imaging of a novel type of magnetic nanoparticle based on Gd-Si oxide, which presents high Gd(3+) atom density. For this purpose, we have used a Prussian Blue analogue as the sacrificial template by reacting with soluble silicate, obtaining particles with nanorod morphology and of small size (75 nm). These nanoparticles present good biocompatibility and higher longitudinal and transversal relaxivity values than commercial Gd(3+) solutions, which significantly improves the sensitivity of in vivo magnetic resonance images.