Surface modification of magnetic nanoparticles with oleylamine and gum Arabic

Magnetic nanoparticles (MNP) were synthesized under acidic conditions in the presence of oleylamine (OLA) and gum Arabic (GA) to study the influence of surface modification on MNP characteristics and cellular level bioactivity. Highly dispersed MNPs were formed from acidic solutions of ferric and ferrous chloride in the absence and presence of OLA. The MNP synthesized in the presence of GA formed large particle aggregates that exhibited rapid coagulation. The three types of MNP were characterized via thermogravimetric analysis (TGA), and dynamic and electrophoretic light scattering to determine particle size and zeta potential. Cytotoxicity and cell interactions were assessed for each of the three MNP samples using L929 fibroblast cells. OLA modified MNPs exhibited the highest level of cytotoxity. Approximately 27% of L929 fibroblast cells died after exposure to OLA modified MNP in comparison to 10% cell death for untreated, GA treated, and control cells. Cells that were exposed to MNPs could be translated in magnetic fields. The OLA and untreated MNPs could be detected in the cell cytoplasm while the GA-modified MNP clusters were located at the cell membrane based on light microscopy.