Interaction Between Nano-Anatase TiO2 and Liver DNA from Mice In Vivo

Abstract
Nano-TiO2 was shown to cause various toxic effects in both rats and mice; however, the molecular mechanism by which TiO2 exerts its toxicity is poorly understood. In this report, an interaction of nano-anatase TiO2 with liver DNA from ICR mice was systematically studied in vivo using ICP-MS, various spectral methods and gel electrophoresis. We found that the liver weights of the mice treated with higher amounts of nano-anatase TiO2 were significantly increased. Nano-anatase TiO2 could be accumulated in liver DNA by inserting itself into DNA base pairs or binding to DNA nucleotide that bound with three oxygen or nitrogen atoms and two phosphorous atoms of DNA with the Ti–O(N) and Ti–P bond lengths of 1.87 and 2.38 Å, respectively, and alter the conformation of DNA. And gel electrophoresis showed that higher dose of nano-anatase TiO2 could cause liver DNA cleavage in mice.