SIMULATION OF THE RADIO-INDUIT DAMAGES BY PHOTONS ON THE DNA MOLECULE IN ITS ENVIRONMENT

Abstract

Monte Carlo codes and equation of diffusion were successively, used to simulate the physical, and physico-chemical, and chemical steps that to estimate the simple and double strand breaks produced on a linear and hydrated DNA model by an incident photons beam. The increase of the biological effectiveness, between 150 and 550 eV, is mainly due to the variation of photon cross section upon the K- ionisation threshold in O,N,C atoms of DNA. In this study we present yields of main radiolysis species (e^-_aq, H, OH) as function of time, then parameterised by the concentration of solute such formicate (HCOO^-). Moreover, we show that, with the same number of absorbed photons, the evolution of breaks as a function of energy reaches a maximum around 450 eV. 

Keywords

• DNA,Monte Carlo,diffusion,yields,solute,photons

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