Maltol-Functionalized Fe3O4 Nanoparticles as T2 Magnetic Resonance Imaging Contrast Agents

We present the use of maltol (3-hydroxy-2-methyl-4H-pyran-4-one) as a capping ligand for iron oxide nanomaterials. Water-soluble maltol-coated Fe3O4 nanoparticles were synthesized by a reductive one-pot synthesis. The nanoparticles were found to be stable in water, and their superparamagnetic properties enabled their application as ultrahigh field T2 magnetic resonance imaging (MRI) contrast agents. High r2 relaxivity and r2/r1 ratios were determined at clinical (B0 = 3 T) and ultrahigh (B0 = 9.4 T) fields, making them on par or superior to current iron-oxide based commercial MRI contrast agents. A low cytotoxic response in three distinct cell types (HUVEC, KB, U343) indicate maltol-coated Fe3O4 nanoparticles are promising T2 MRI contrast agents.