A New Electrochemical Approach for the in Vitro Investigation of Damage in Native DNA by Small γ-radiation Doses

Summary

Voltammetry provides a new method to assess γ-radiation damage to native DNA in vitro after low doses of irradiation. Using single sweep voltammetry at a stationary mercury electrode a substantial labilization of the double helical conformation of γ-irradiated DNA was found. Up to 40 Gy a linear dose-effect relationship exists reflected for the number of strand breaks and the number of destabilized base pairs. A considerable difference in the frequency of formation of the two kinds of radiation damage is seen in the ratio of their G-values. Base pair labilization occurs depending on aeration conditions 200 to 300 times more frequently than the formation of a single strand break.