CONICET | Buscador de Institutos y Recursos Humanos

Understanding the radiation-induced effects at the cellular level is of prime importance forpredicting the future of irradiated biological organisms. Thus, whether it is in radiobiology toidentify the DNA critical lesions or in medicine to adapt the radio-therapeutic protocols, anaccurate knowledge of the numerous interactions induced by charged particles in living matter isrequired. To do that, Monte-Carlo track-structure codes represent the most suitable and powerfultools, in particular for modeling the full slowing-down of the ionizing particles in biological matter.However, it is worth mentioning that such numerical codes are reliable only if the input databaseused for modeling the charged particle induced interactions is precise and complete. In thiscontext, the literature reports several numerical codes for proton and electron transport in water,the latter being commonly used as surrogate of the living medium.The current work aims at going beyond this artifice with the development of an event-by-eventMonte Carlo code - called TILDA-V - based on a complete set of multiple-differential and totalcross sections for describing all the inelastic and elastic processes occurring throughout theslowing-down of protons in water and DNA [1]. TILDA-V (an acronym for Transport d?Ions LourdsDans Aqua & Vivo). It is currently based on a complete set of quantum-mechanical cross sectionsfor all the electron- and proton/hydrogen-induced interactions in water as well as in biologicaltargets including the DNA nucleobases and the sugar-phosphate backbone.Finally, a realistic description of the biological medium has been considered by modeling a typicalnucleotide equivalent unit of hydrated DNA, namely, a nucleobase-pair plus a sugar phosphategroup both surrounded by a hydration shell composed by 18 water molecules [2]. Intra-comparisons between water and hydrated DNA in terms of proton range and stopping power willbe presented in this work.