Adam Konefał1, Wioletta Lniak1, Justyna Rostocka1, Andrzej Orlef2, Maria Sokół2, Janusz Kasperczyk3, Paulina Jarząbek3, Aleksandra Wrońska4, Katarzyna Rusiecka4. 1. Institute of Physics, University of Silesia in Katowice, Katowice, Poland. 2. Maria Sklodowska-Curie National Research Institute of Oncology, Gliwice Branch, Department of Medical Physics, Gliwice, Poland. 3. Centre of Polymer and Carbon Materials, Polish Academy of Sciences, Zabrze, Poland. 4. Marian Smoluchowski Institute of Physics, Jagiellonian University, Kraków, Poland.
Abstract
AIM: This work is focused on the Monte Carlo microdosimetric calculations taking into account the influence of the AuNPs' shape, size and mass concentration on the radiation dose enhancement for the high-energy 6 MV and 18 MV X-ray therapeutic beams from a medical linac. BACKGROUND: Due to a high atomic number and the photoelectric effect, gold nanoparticles can significantly enhance doses of ionizing radiation. However, this enhancement depends upon several parameters, such as, inter alia, nanoparticles' shape etc. METHOD: The simulated system was composed of the therapeutic beam, a water phantom with the target volume (with and without AuNPs) located at the depth of the maximum dose, i.e. at 1.5 cm for the 6 MV beam and at 3.5 cm for the 18 MV one. In the study the GEANT4 code was used because it makes it possible to get a very short step of simulation which is required in case of simulating the radiation interactions with nanostructures. RESULTS: The dependence between the dose increase and the mass concentration of gold was determined and described by a simple mathematical formula for three different shapes of gold nanoparticles - two nanorods of different sizes and a flat 2D structure. The dose increase with the saturation occurring with the increasing mass concentration of gold was observed. CONCLUSIONS: It was found that relatively large cylindrical gold nanoparticles can limit the increase of the dose absorbed in the target volume much more than the large 2D gold nanostructure.
AIM: This work is focused on the Monte Carlo microdosimetric calculations taking into account the influence of the AuNPs' shape, size and mass concentration on the radiation dose enhancement for the high-energy 6 MV and 18 MV X-ray therapeutic beams from a medical linac. BACKGROUND: Due to a high atomic number and the photoelectric effect, gold nanoparticles can significantly enhance doses of ionizing radiation. However, this enhancement depends upon several parameters, such as, inter alia, nanoparticles' shape etc. METHOD: The simulated system was composed of the therapeutic beam, a water phantom with the target volume (with and without AuNPs) located at the depth of the maximum dose, i.e. at 1.5 cm for the 6 MV beam and at 3.5 cm for the 18 MV one. In the study the GEANT4 code was used because it makes it possible to get a very short step of simulation which is required in case of simulating the radiation interactions with nanostructures. RESULTS: The dependence between the dose increase and the mass concentration of gold was determined and described by a simple mathematical formula for three different shapes of gold nanoparticles - two nanorods of different sizes and a flat 2D structure. The dose increase with the saturation occurring with the increasing mass concentration of gold was observed. CONCLUSIONS: It was found that relatively large cylindrical gold nanoparticles can limit the increase of the dose absorbed in the target volume much more than the large 2D gold nanostructure.
Authors: Irshad Hussain; Susan Graham; Zhenxin Wang; Bien Tan; David C Sherrington; Steven P Rannard; Andrew I Cooper; Mathias Brust Journal: J Am Chem Soc Date: 2005-11-30 Impact factor: 15.419
Authors: Yuting Lin; Stephen J McMahon; Matthew Scarpelli; Harald Paganetti; Jan Schuemann Journal: Phys Med Biol Date: 2014-12-21 Impact factor: 3.609