DNA damage by soft X-ray exposure at oxygen K-edge

1st Conference on Light and Particle Beams in Materials Science 2013

物理学;材料科学

Sugaya, Y.^1,2 ; Narita, A.^2 ; Fujii, K.^2 ; Yokoya, A.^1,2

Ibaraki University, Mito Ibaraki 310-8512, Japan^1

ASRC, JAEA, Tokyo Ibaraki 319-1195, Japan^2

关键词: Biochemical treatments;    K-shell electrons;    K-shell ionization;    Oxygen atom;    Oxygen K-edge;    Photoabsorptions;    Physico-chemical mechanisms;    Strand breaks;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/502/1/012040/pdf
DOI  :  10.1088/1742-6596/502/1/012040

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

In order to obtain detailed insights into the physicochemical mechanism of DNA damage induction in terms of photoabsorption modes, we have prepared thin DNA films of closed circular plasmid (pUC18) on a cover slip without any additives. Using this film, we have performed preliminary experiments by exposing to soft X-rays with energies around oxygen K-shell ionization threshold. The DNA damage yields of strand breaks and base lesions or AP sites were quantified by biochemical treatments. We confirmed that the DNA film can work as a specimen irradiation. The DNA damage yields induced by π* excitation of a K-shell electron of oxygen atoms in DNA were significantly larger those for oxygen K-ionization.