Aqueous Synthesis of Polyhedral "Brick-Like" Iron Oxide Nanoparticles for Hyperthermia and T2 MRI Contrast Enhancement, and for Targeting Endothelial Cells for Therapeutic Delivery
A low temperature, aqueous synthesis of polyhedral iron oxide nanoparticles (IONPs) is presented. The modification of the co-precipitation hydrolysis method with Triton X surfactants results in the formation of crystalline polyhedral particles. The particles are herein termed iron oxide “nanobricks” (IONBs), as the varieties of particles made are all variations on a simple “brick-like”, polyhedral shape such as rhombohedral shape or parallelogram as evaluated by TEM. These IONBs can be easily coated with hydrophilic silane ligands, allowing them to be dispersed in aqueous media. The dispersed particles are investigated for potential applications as hyperthermia and T2 MRI contrast agents. The results demonstrate that the IONBs perform better than comparable spherical IONPs in both applications, and show r2 values amongst the highest for iron oxide based materials reported in the literature.