Point Defects in Double Helix Induced by Interaction of Silver   Nanoparticles with DNA
  Interaction of DNA-silver nanoparticles (AgNPs) complexes with H3O+, Cu2+ and Cl- has been studied by spectro-photometric, spectro-fluorimetric and differential scanning micro calorimetric methods. It is shown that DNA is a catalyst in redox reactions taking place in AgNPs adsorbed on its surface. We also demonstrate that Ag+ ions that are freed after corrosion of nanoparticles show absorption into the inner part of DNA double helix, i.e. they make the so-called cross-links between complementary base pairs of DNA. The cross-links present point defects of DNA which leads in-vivo to cell death. 
Vasil G. Bregadze, Zaza G. Melikishvili, Tamar G. Giorgadze, Jamlet R.   Monaselidze, Zaza V. Jaliashvili, Temur B. Khuskivadze
physics.bio-ph