Stability of dry Phage Lambda DNA irradiated with swift heavy ions. (September 2019) - Karganov, M. Yu
Abstract: Effects of irradiations of Phage Lambda dry DNA samples at room and cryogenic temperatures with 158 MeV Xe and 48 MeV Ar ions were investigated. These ions primary transfer energy into the electronic subsystem of a target: dE/dx = S e, S e Xe = 10.8 keV/nm and S e Ar = 3.5 keV/nm. Site-specific enzymes restriction endonucleases were applied to indicate DNA damages induced by these ions. Electrophoresis was applied to analyze the dependencies of the distributions of DNA fragments sizes on the ion fluence ranging from 10 8 cm −2 to 10 10 cm −2 . Electron paramagnetic resonance (EPR) technique was used to investigate damages of a dry DNA sample irradiated at the cryogenic temperature (140 K) with 158 MeV 132 54 Xe 26+ ions up to the fluence 8.6·10 9 cm −2 . A poorly resolved signal centered at the g -factor value for the free electron g ≈ g e was detected, which probably results from a mixture of different-type radicals trapped in the DNA film. The total concentration of paramagnetic species in this sample was estimated to be 1.3 × 10 19 spin/g. Highlights: Damages created in irradiated dry DNA by swift heavy ions were studied by electrophoresis. The inverse dependence between the portion of large DNA fragments and ion fluence is presented. Restriction analysis of irradiated DNA is informative for damage reveal.