Superparamagnetic iron oxide nanoparticles (SPIONs): Green preparation, characterization and their cytotoxicity effects

Superparamagnetic iron oxide nanoparticles (SPIONs; Fe3O4) were prepared by the covalent binding of starch onto the surface of magnetic Fe3O4 nanoparticles, by a “green” co–precipitation method. The scanning electron microscopy (SEM) illustrated the regular spheres of Fe3O4 particles that were coated by starch molecules to be regular spheres with a mean diameter of about 40nm. Powder X–ray diffraction patterns (PXRD) indicated that the prepared samples were pure Fe3O4 with a spinel structure while the coating of starch did not result in a phase change. The starch coating onto the Fe3O4 nanoparticles was also demonstrated by Fourier transform infrared (FTIR) spectra. Magnetic measurements revealed that the saturated magnetization of the starch–SPIONs reached 42.1emu/g, having nanoparticles with the characteristics of superparamagnetism, while a dose dependent toxicity with non–toxic effect of concentration below 62.5µg/mL was observed in the studies of in vitro cytotoxicity on neuro2A cells.