OICC Press Journal of Nanostructure in Chemistry 2193-8865 3 1 (December 2013) 2013 03 27 A study on the assessment of DNA strand-breaking activity by silver and silica nanoparticles 10.1186/2193-8865-3-7 EN Ali R Vahdati Young Researchers Club, Tonekabon Branch, Islamic Azad University, Tonekabon, IR Babak Sadeghi Department of Chemistry, Tonekabon Branch, Islamic Azad University Tonekabon, Tonekabon, IR Journal Article 2013 03 27 Abstract We measured the DNA strand-breaking activity of nanoparticle by agarose gel electrophoresis. Plasmid DNA was mixed with nanosilver and nano-silica powders in an aqueous solution. Then the mixture was applied to 1% of agarose gel electrophoresis at 75 V for 30 min. We used 300 nm of UV irradiation in order to visualize the DNA bands. The DNA strand-breaking activity of nanomaterial was measured through measuring the reduction of super-coiled DNA to circular form of DNA.