Estimation of single-strand breaks induced in the dried film of DNA by high energy alpha particle from a cyclotron.

DNA extracted and purified from Vibrio cholerae OGAWA 154 cells and prepared in the form of a dry thin film was exposed in air to a beam of alpha particles obtained from a Variable Energy Cyclotron. The number of single-strand breaks per DNA unit exhibited a linear dose-effect relationship indicating the occurrence of single-hit kinetics. The efficiency and yield of alpha-induced single-strand breaks were approximately 72 eV/break and 1.39 respectively.