Facile synthesis of superparamagnetic manganese ferrite nanoparticles as a novel T2 MRI contrast agent

With co-precipitation method we successfully synthesized an aqueous dispersible, superparamagnetic manganese ferrite nanoparticles at relatively low temperature (190 ​°C). This material shows potential application as T 2 MRI contrast agent. Cost-effective and less toxic manganese (II) chloride (MnCl 2 ·4H 2 O) and iron (III) chloride hexahydrate (FeCl 3 ·6H 2 O) were used as precursors and 2-[2-(2-Hydroxyethoxy)ethoxy] ethanol (TEG) were utilized as solvent which served as stabilizer and provided a reduction system. The mean diameter of these nanoparticles is about 7 ​nm. Its saturation magnetization (Ms) and relaxivity value (r 2 ) are as high as 46 emu/g and 593.9 ​mM −1 s −1 respectively. In vitro cell study demonstrated pancreatic cancer cells could keep viable when the manganese ferrite nanoparticles concentration reached up to 50 ​μg/mL.