Cytotoxicity of polystyrene nanospheres internalization in mouse fibroblast cells

With development of nanotechnology application, industry and government regulators notice that nanomaterials, especially nanoparticles, have some potential intimidation for human health and environmental safety. In this work, the cytotoxicity of 20 nm and 200 nm polystyrene nanospheres was investigated in cultured L929 fibroblast cells. There was an obvious difference of cytotoxicity between 20 and 200 nm polystyrene nanospheres because of their size effect. With increase concentration of 20 nm polystyrene nanospheres, L929 cells became round, even shrinkage in shape, whereas cells cultured with 200 nm polystyrene nanospheres were well spreading at these concentrations. With exposure to 20 nm polystyrene nanospheres, TEM image showed that lysosomes were enhanced and cytoplasm organelles were damaged. There was a significant increase exceeding oxidative stress for different concentration of 20 nm polystyrene nanospheres, with increasing of lactate dehydrogenase (LDH) and decreasing of methyl tetrazolium cytotoxicity (MTT). Possible mechanisms involved in the cytotoxicity of polystyrene nanospheres were also discussed.