Seminar: Enhanching Radiotherapy with High-Z doped Nitroimidazoles
Aula PaoluziTitle: Enhanching Radiotherapy with High-Z doped Nitroimidazoles
Speaker: Pamela Svensson
Abstract: Radiosensitisers (RSs) are compounds that make cancer cells more sensitive to radiotherapy. For the sensitising effect to take place, these compounds need to be
activated by radiation. Yet, the atomic and molecular level mechanisms of this activation are poorly understood, resulting in a lack of comprehension as to why some RSs are better than others. We have studied nitroimidazole-based RSs, which utilise doping of high-Z element iodine as the photoabsorption antenna, using a combined experimental/theoretical approach.
The nitroimidazoles are known to accumulate in oxygen-deficient (hypoxic) regions, which is often the case for many tumours of a larger size. There, the nitroimidazole can, via the release of the nitro group, affect the repair mechanisms in the cancer cell. Using synchrotron light tuned to the K- and L-edges of the samples, and thereby isolating the dominating ionisation site, we have studied fragmentation mechanisms and the production of harmful secondary species from the dissociation of these imidazoles. To complement the experiments, we have employed BornOppenheimer-based molecular dynamics simulations to investigate the integrity of the intramolecular bonds and follow fragmentation pathways from the site-specific ionisation. These studies have so far been performed while the RS have been in the gas phase and isolated from nearby molecules, and only recently, we can show new results on radiation damage of this molecular bioagent during monosolvation.
Poster
