In vitro cytotoxicity screening of water-dispersible metal oxide nanoparticles in human cell lines

In this study, we present in vitro cytotoxicity of iron oxide (Fe3O4) and manganese oxide (MnO) using live/dead cell assay, lactate dehydrogenase assay, and reactive oxygen species detection with variation of the concentration of nanoparticles (5-500 mu g/ml), incubation time (18-96 h), and different human cell lines (lung adenocarcinoma, breast cancer cells, and glioblastoma cells). The surface of nanoparticles is modified with polyethyleneglycol-derivatized phospholipid to enhance the biocompatibility, water-solubility, and stability under an aqueous media. While the cytotoxic effect was negligible for 18 h incubation even at highest concentration of 500 mu g/ml, MnO nanoparticle represented higher level of toxicity than those of Fe3O4 and the commercial medical contrast reagent, Feridex after 2 and 4 day incubation time. However, the cytotoxicity of Fe3O4 is equivalent or better than Feridex based on the live/dead cell viability assay. The engineered MnO and Fe3O4 exhibited excellent stability compared with Feridex for a prolonged incubation time.