Induced temperature-dependent DNA degradation by C 60 without photoactivation - Liang Yong

This study shows that C60 can degrade pBR322 plasmid DNA at room temperature without photoactivation. The degradation was enhanced by increasing incubation temperature, reaction time or C60 concentration. We also found that superoxide radical anions (O 2 −· ) were formed in the C60 solution. Superoxide dismutase significantly inhibited DNA cleavage and O 2 −· generation induced by C60. These results suggest that DNA cleavage was caused by the formation of reactive oxygen species induced by C60 at room temperature. Furthermore, we demonstrate that the DNA degradation was significantly inhibited by acid amide chemicals such as formamide, and by increased ionic strength of the reaction solution. These results indicate that the DNA conformation stability and the surface properties of C60 are important factors regulating DNA …