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.