Description Application Functional shell formation with ceric ammonium nitrate (CAN, Ce-(NH4)2(NO3)6) on nanometer sized maghemite (γ-Fe2O3) particles has been shown to promote the binding of oxidized polyethyleneimine (PEI) to their surface, which mitigates their acute in vivo toxicity and enables the applications of cerium doped maghemite nanoparticles in high efficacy gene silencing. The addition of the alginic acid to the shell enables excellent biocompatibility and surface functionality (carboxylic acid) for facile functionalization of choice targeting ligands. In addition these nanoparticles find applications in magnetic resonance imaging (MRI) and drug delivery. Legal Information The Product is being introduced through Materials Transfer Agreement with ′Bar Ilan University, Israel′.