RGDC Functionalized TitaniumDioxide Nanoparticles Induce Less Damage to Plasmid DNA but HigherCytotoxicity to HeLa Cells.

In this paper, nano-TiO2was functionalizedby different methods, and its genotoxicity and cytotoxicity were studiedin detail. The genotoxicity of nano-TiO2was evaluatedby observing its interactions with pUC19 plasmid DNA at a single moleculelevel using atomic force microscopy. The results show that with theassistance of UVA radiation, RGDC functionalized nano-TiO2induced less damage to plasmid DNA than unmodified ones. The HeLacell-specific PDT effect was investigated by cytotoxicity assay correspondingly.RGDC-functionalized nano-TiO2shows the highest killingeffect to HeLa cells with the assistance of UVA radiation. The reasonsthat cause the contradiction between genotoxicity and cytotoxicitywere analyzed, and the molecular mechanisms of the PDT effects werediscussed. The results show that the genotoxicity of nano-TiO2to plasmid DNA and its cytotoxicity to HeLa cells are relatedbut also different. The RGDC functionalization is an effective methodto increase the cytotoxicity of nano-TiO2. [ABSTRACT FROM AUTHOR]