Decomposition of 2-deoxy-D-ribose by irradiation with 0.6 keV electrons and by 0.5 keV ultrasoft X-rays.
OBJECTIVE
To compare the molecular decomposition of 2-deoxy-D-ribose induced by 0.6 keV electron irradiation or by 0.5keV ultrasoft X-ray irradiation.


METHODS
A thin film of 2-deoxy-D-ribose was irradiated by two radiation sources: low-energy (approximately 0.6 keV) electrons and ultrasoft X-rays (approximately 0.5 keV). The positive ions that were desorbed from the sample during the irradiation were measured using a quadrupole mass spectrometer. The spectral changes in the X-ray absorption near edge structure (XANES) were also examined after the irradiation.


CONCLUSIONS
The ions that were desorbed from 2-deoxy-D-ribose due to electron irradiation were mainly H+, CHx+, C2Hx+, CO+, CHxO+, C3Hx+, C2HxO+ and C3sHO+ (x=1, 2, and 3) ions. These ions were the same as those observed in desorption due to ultrasoft X-ray irradiation. The XANES spectral changes induced by electron irradiation showed C-O bond cleavage in the molecule and C=O bond formation in the surface residues. These results show that intensive molecular decomposition of the furanose ring structure was induced by both types of irradiation. It is inferred that these irradiation products are primarily produced by secondary electrons (several tens of eV), which are thought to be generated by both types of irradiation when they are applied to the 2-deoxy-D-ribose sample.
Fujii
Kentaro
K
Radiation Risk Analysis Laboratory, Japan Atomic Energy Research Institute, 2-4 Shirakatashirane, Tokai, Ibaraki 319-1195 Japan. fujiken@riskest.tokai.jaeri.go.jp
Akamatsu
Ken
K
Yokoya
Akinari
A
D003855:Deoxyribose / Q000737:chemistry* / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D004583:Electrons; D008968:Molecular Conformation / Q000528:radiation effects; D011829:Radiation Dosage; D014965:X-Rays
D003855:Deoxyribose