Near-ambient-pressure XPS as as tool to monitor DNA radiation damage directly in water
- Ionizing radiation damage to DNA plays a fundamental role in cancer therapy. X-ray photoelectron-spectroscopy (XPS) allows simultaneous irradiation and damage monitoring. Although water radiolysis is essential for radiation damage, all previous XPS studies were performed in vacuum. Here we present near-ambient-pressure XPS experiments to directly measure DNA damage under water atmosphere. They permit in-situ monitoring of the effects of radicals on fully hydrated double-stranded DNA. The results allow us to distinguish direct damage, by photons and secondary low-energy electrons (LEE), from damage by hydroxyl radicals or hydration induced modifications of damage pathways. The exposure of dry DNA to x-rays leads to strand-breaks at the sugar-phosphate backbone, while deoxyribose and nucleobases are less affected. In contrast, a strong increase of DNA damage is observed in water, where OH-radicals are produced. In consequence, base damage and base release become predominant, even thoughIonizing radiation damage to DNA plays a fundamental role in cancer therapy. X-ray photoelectron-spectroscopy (XPS) allows simultaneous irradiation and damage monitoring. Although water radiolysis is essential for radiation damage, all previous XPS studies were performed in vacuum. Here we present near-ambient-pressure XPS experiments to directly measure DNA damage under water atmosphere. They permit in-situ monitoring of the effects of radicals on fully hydrated double-stranded DNA. The results allow us to distinguish direct damage, by photons and secondary low-energy electrons (LEE), from damage by hydroxyl radicals or hydration induced modifications of damage pathways. The exposure of dry DNA to x-rays leads to strand-breaks at the sugar-phosphate backbone, while deoxyribose and nucleobases are less affected. In contrast, a strong increase of DNA damage is observed in water, where OH-radicals are produced. In consequence, base damage and base release become predominant, even though the number of strand-breaks increases further.…
Autor*innen: | Marc Benjamin HahnORCiD |
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Weitere Person: | Paul M. Dietrich, Jörg RadnikORCiD |
Dokumenttyp: | Posterpräsentation |
Veröffentlichungsform: | Präsentation |
Sprache: | Englisch |
Jahr der Erstveröffentlichung: | 2023 |
Organisationseinheit der BAM: | 6 Materialchemie |
6 Materialchemie / 6.1 Oberflächen- und Dünnschichtanalyse | |
6 Materialchemie / 6.6 Physik und chemische Analytik der Polymere | |
DDC-Klassifikation: | Naturwissenschaften und Mathematik / Chemie / Analytische Chemie |
Freie Schlagwörter: | Base damage; Base loss; Cancer treatment; DNA; DNA radiation damage; Direct damage; Dissociative electron attachment (DEA); Dissociative electron transfer (DET); Dosimetry; Double-strand break (DSB); ESCA; Energy deposit; G5P; Geant4; Geant4-DNA; Hydrated DNA; Hydrated electron; Hydration shell; Hydroxyl radical; Indirect damage; Ionisation; Ionization; LEE; Low energy electrons; MCS; Microdosimetry; NAP-XPS; Near ambient pressure xray photo electron spectroscopy; Net-ionization reaction; OH radical; PES; Particle scattering; Prehydrated electron; Presolvated electron; Protein; Quasi-direct damage; ROS; Radiation damage; Radiation therapy; Radical; Radiolysis; Radiotherapy; Reactive oxygen species; Simulation; Single-strand break (SSB); Single-stranded DNA-binding proteins; TOPAS; TOPAS-nbio; XPS; Xray; Xray photo electron spectrocopy |
Themenfelder/Aktivitätsfelder der BAM: | Chemie und Prozesstechnik |
Veranstaltung: | Miller Conference |
Veranstaltungsort: | Furiani, France |
Beginndatum der Veranstaltung: | 03.06.2023 |
Enddatum der Veranstaltung: | 08.06.2023 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 13.06.2023 |
Referierte Publikation: | Nein |