Simulation and Experimental Verification of DNA Damage Due to X-Rays Interaction

Alexandra Pinto Castellanos

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arXiv · 1810.05815

Simulation and Experimental Verification of DNA Damage Due to X-Rays Interaction

Alexandra Pinto Castellanos

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Abstract

This paper describes the model for DNA in MATLAB taking into account all of component atoms. In this model, it is possible to generate sequences with length 10000 basis pairs available for introducing all types of sequences. Once the strands are generated, it is studied the DNA damage in the single strand and double strand. The damage are outcomes of ionising radiation of X-rays when interacting with the DNA immersed in water. This is a theoretical and experimental in-vitro study that quantifies the single strand and double strand damage for different doses of radiation. This can be useful to predict the exact risks of expositions to radiations. In simulations, it is taken into account the damage caused by free electrons generated by the effect of the interaction with the water molecules, this is different to the effect considered in radiobiology, where indirect damages are due to chemical reactions. The spatial distribution of the electrons is obtained from Geant4 and here this distribution is used for the creation of rays as three-dimensional random trajectories through Monte Carlo simulations. It is also presented the experimental DNA damage through radiating DNA samples immersed in water with a X-rays unit with Molybdenum target. The damage level is quantified through Atomic Force Microscopy (AFM). It is possible to conclude a direct relation between the damage and the radiation doses with the experimental results.

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Alexandra Pinto Castellanos. 2019-05-11. Simulation and Experimental Verification of DNA Damage Due to X-Rays Interaction. https://arxiv.org/abs/1810.05815

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