Amino covalent binding approach on iron oxide nanoparticle surface: Toward biological applications

We report on the synthesis and the surface modification of different types of magnetic iron oxide particles by developing an original process based on diazonium salts chemistry. Particles were first coated with amino groups and then subjected to polyethylene glycol (PEG) surface modification. They were subsequently characterized by transmission electron microscopy, infrared spectroscopy, diffraction light scattering and by Zeta potential. To show the efficiency of this surface modification method, the potential cytotoxicity and (pro-)inflammatory effect of the PEG magnetic particles were also analyzed in vitro. This covalently surface modification approach based on diazonium salts chemistry provides individually dispersed, PEG-modified magnetic nanoparticles suitable for biological applications.