DNA strand breaks induced by soft X-ray pulses from a compact laser plasma source

0464879 - ÚJF 2017 RIV GB eng J - Journal Article
Adjei, D. - Wiechec, A. - Wachulak, P. - Ayele, M. G. - Lekki, J. - Kwiatek, W. M. - Bartnik, A. - Davídková, Marie - Vyšín, Luděk - Juha, Libor - Pina, L. - Fiedorowicz, H.
DNA strand breaks induced by soft X-ray pulses from a compact laser plasma source.
Radiation Physics and Chemistry. Roč. 120, MAR (2016), s. 17-25. ISSN 0969-806X. E-ISSN 1879-0895
R&D Projects: GA ČR GA13-28721S; GA ČR(CZ) GBP108/12/G108
EU Projects: European Commission(XE) 284464 - LASERLAB-EUROPE
Institutional support: RVO:68378271 ; RVO:61389005
Keywords : laser-produced plasma * soft X-rays * radiobiology * gas puff target * water window * DNA strand break
Subject RIV: BO - Biophysics
Impact factor: 1.315, year: 2016

Application of a compact laser plasma source of soft X-rays in radiobiology studies is demonstrated. The source is based on a laser produced plasma as a result of irradiation of a double-stream gas puff target with nanosecond laser pulses from a commercially available Nd:YAG laser. The source allows irradiation of samples with soft X-ray pulses in the "water window" spectral range (wavelength: 2.3-4.4 nm; photon energy: 280-560 eV) in vacuum or a helium atmosphere at very high-dose rates and doses exceeding the kGy level. Single-strand breaks (SSB) and double-strand breaks (DBS) induced in DNA plasmids pBR322 and pUC19 have been measured. The different conformations of the plasmid DNA were separated by agarose gel electrophoresis. An exponential decrease in the supercoiled form with an increase in linear and relaxed forms of the plasmids has been observed as a function of increasing photon fluence. Significant difference between SSB and DSB in case of wet and dry samples was observed that is connected with the production of free radicals in the wet sample by soft X-ray photons and subsequent affecting the plasmid DNA. Therefore, the new source was validated to be useful for radiobiology experiments.
Permanent Link: http://hdl.handle.net/11104/0263630