PEG-Iron Oxide Core-Shell Nanoparticles: In situ Synthesis and In vitro Biocompatibility Evaluation for Potential T 2 -MRI Applications

Several colloidal nanosystems have been developed aiming biomedical applications that include investigations related to magnetic resonance imaging (MRI) procedures. In this work, a core-shell structure consisting of iron oxide nanoparticles (IONPs) nucleus grafted with polyethylene glycol (PEG) 4000 was prepared and evaluated by physicochemical and magnetic characterization. The polymer was covalently immobilized over nanoparticles through a simple and rapid in situ chemical method. The resulting hybrid material was capable of inducing a relevant T 2 relaxation time in an average compared to marketed MRI formulations, revealing both physical characteristics and magnetic properties adequate for MRI applications. Furthermore, the in vitro biocompatibility profile was assessed by flow cytometry technique, using healthy human cell lineage (HEK-293). The results indicated good biocompatibility profile and non-anti-proliferative properties, and therefore, IONP-PEG can be considered as a new system candidate as a T 2 contrast agent for MRI applications.