Study On The Biocompatibility Between Nano-Ferroferric Oxide And HeLa Cell

With the rapid development of nano technology, nano-technology has been applied to all areas of our lives-industrial, food and medical. Magnetic nano-materials is an important part in nano-technology, because of their own with magnetic, they can accurately reach the target site with magnet out of the body, it has a very broad application prospects, such as building the drug targeting system,targeted gene therapy, cancer hyperthermia, intensifier for magnetic resonance image and so on. As the Fe3O4 is one of the material with highest value and widely use, we need to research their safety dose in vivo.We have two ways to study the biosafety of Fe3O4-oxidative damage and genotoxicity.Many studies have shown that the normal metabolism of the body can produce reactive oxygen species(ROS), which has strong oxidation, is the key of human diseases and aging. The ROS produced by mitochondrial in the body's can be removed by other mechanisms, such as glutathione, superoxide dismutase enzymes. So we choose to measure intracellular reactive oxygen species, glutathione, superoxide dismutase and malondialdehyde(MDA) as the biomarker evaluation of oxidative damage. In vivo, the role of reactive oxygen species produce peroxidation, the end product of lipid oxidation is malondialdehyde. MDA will lead proteins, nucleic acids and other biological macromolecules to polymerization and crosslinking, has a certain degree of cellular toxicity. So the level of MDA evaluation is widely used indicators.We has been found that oxygen ROS can cause oxidative damage to cells DNA strand breaks, also cause DNA chain cross-linking, including DNA-DNA cross-linking and DNA-protein crosslinks. DNA damage affects cell function and DNA self-repair, which will increase the human disease, especially the incidence of cancer. So we choose assayed for DNA-protein cross connection number and the comet assay to evaluate DNA damage and genetic toxicity.From the experimental results can be seen that the use of low dose does not cause obvious cell injury and genotoxicity. When the concentration of nano-Fe3O4 less than 100μg/ml, the seven biosafety evaluation methods were no significant differences, indicating that the material was applied to the body in the future is possible. However, in vitro, has its limitations:first, can not accurately simulate the human body environment, the experimental results obtained will have a certain bias; Second, the data can only be used in doses, can not know the material in the human metabolic process and discharge mode and estimate whether the side-effects on the human body; third, it needs to explore in vivo through the use of more appropriate dosage.