In situ monitoring of the influence of water on DNA radiation damage by near-ambient pressure X-ray photoelectron spectroscopy.
| Autor: | Hahn MB; Institut für Experimentalphysik, Freie Universität Berlin, Berlin, Germany. hahn@physik.fu-berlin.de.; Bundesanstalt für Materialforschung und -prüfung, Berlin, Germany. hahn@physik.fu-berlin.de., Dietrich PM; SPECS Surface Nano Analysis GmbH, Berlin, Germany., Radnik J; Bundesanstalt für Materialforschung und -prüfung, Berlin, Germany. |
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| Jazyk: | angličtina |
| Zdroj: | Communications chemistry [Commun Chem] 2021 Apr 09; Vol. 4 (1), pp. 50. Date of Electronic Publication: 2021 Apr 09. |
| DOI: | 10.1038/s42004-021-00487-1 |
| Abstrakt: | 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 though the number of strand-breaks increases further. (© 2021. The Author(s).) |
| Databáze: | MEDLINE |
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