Dextran-coated superparamagnetic amorphous Fe–Co nanoalloy for magnetic resonance imaging applications

• Amorphous Fe–Co nanoalloy was prepared via wet chemical reduction approach.
• The Fe–Co nanoalloy is water-soluble, stable, and biocompatible.
• The Fe–Co nanoalloy is superparamagnetic.
• The Fe–Co nanoalloy exhibits T2-weighted MR enhancement both in vitro and in vivo.

For magnetic resonance imaging applications, a facile approach for water-soluble dextran coated amorphous Fe–Co nanoalloy was developed. The as-synthesized nanoalloy had a diameter of 9 nm with a narrow size distribution and showed superparamagnetic property with a saturated magnetization (Ms) of 25 emu/g. In vitro cytotoxicity test revealed that it was biocompatible at a concentration below 120 μg/mL. It can be uptaken by HeLa cells effectively and resulted in the obvious T2 effect after internalization. Biodistribution studies in conjunction with inductively coupled plasma-atomic emission spectroscopy (ICP-AES) confirmed that Fe–Co nanoalloy was preferentially accumulated in lung and spleen after intravenous injection for 4 h. In vivo MRI, dextran-coated Fe–Co nanoalloy can serve as a sensitive contrast agent for MR imaging, especially in the spleen, so we believe that it maybe hold great promise for diagnosis of splenic disease by appropriately functionalizing their surface.

A dextran-coated Fe–Co nanoalloy was developed serving as a sensitive contrast agent for magnetic resonance imaging applications.Figure optionsDownload as PowerPoint slide