Investigation of Auger Electron Emitting Radionuclides Effects in Therapy Using the Geant4-DNA Toolkit: A Simulation Study

Purpose: The biological effects of ionizing radiation at the cellular and subcellular scales are studied by the number of breaks in the DNA molecule that provides a quantitative description of the stochastic aspects of energy deposition at cellular scales. The Geant4 code represents a suitable theoretical toolkit in microdosimetry and nanodosimetry. In this study, radiation effects due to Auger electrons emitting radionuclides such as 195mPt 113mIn, 125I and 201Tl are investigated using the Geant4-DNA. Materials and Methods: The Geant4-DNA is the first Open-access software for the simulation of ionizing radiation and biological damage at the DNA scale. Low-energy electrons, especially Auger electron from Auger electron emitting radionuclides during the slowing-down process, deposit their energy within a nanometer volume. Results: The average number of Single-Strand Breaks (SSB) and Double-Strand Breaks (DSB) of DNA as a function of energy and distance from the center of the DNA axis are shown. Conclusion: The highest DSBs yield has occurred at energies less than 1 keV, and  induces a higher DSBs yield.