Auger effects on bromo-deoxyuridine-monophosphate irradiated with monochromatic X-rays around bromine K-absorption edge
Auger effects on bromo-deoxyuridine-monophosphate irradiated with monochromatic X-rays around bromine K-absorption edge
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溴 K 吸收边附近单色 X 射线照射对溴脱氧尿苷单磷酸的俄歇效应
DOI：
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发表时间：
1989
影响因子：
1.7
通讯作者：
K. Takakura
中科院分区：
文献类型：
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作者：
K. Takakura
为了研究俄歇级联的增强效应，使用同步辐射作为光源，用13.49 keV和13.43 keV的单色X射线照射溴脱氧尿苷一磷酸（Br-dUMP）水溶液样品，刚好在溴的K吸收限之上和之下。使用高效液相色谱法分离辐解产物，如脱氧尿苷-单磷酸（dUMP）、尿嘧啶和溴-尿嘧啶（Br-尿嘧啶）。定量分析了它们的量作为含Br-dUMP溶液中X射线能量吸收剂量的函数，并根据吸收能量计算了这些产物的G值。作为结果，在13.49 keV和13.43 keV的X射线之间，来自Br-dUMP的辐解产物的G值的比率对于dUMP为2.2，对于Br-尿嘧啶为1.02，对于尿嘧啶为1.23，清楚地表明能量依赖性增强。另一方面，在13.49 keV和13.43 keV的X射线之间，观察到dUMP在水溶液中照射释放的尿嘧啶的G值几乎没有显著差异。这似乎证实了来自溴原子K壳层的俄歇电子可能在这些辐解产物的诱导中起着能量依赖性增强的主要作用。
SummaryIn order to study the enhanced effect by Auger cascade, samples of bromo-deoxyuridine-monophosphate (Br-dUMP) in aqueous solutions were irradiated with monochromatic X-rays at 13.49 keV and 13.43 keV, just above and below the K-absorption edge of bromine, using synchrotron radiation as a source. Radiolytic products such as deoxyuridine-monophosphate (dUMP), uracil and bromo-uracil (Br-uracil) were isolated using high performance liquid chromatography. Their amounts were quantitatively analysed as a function of the absorbed dose in the solutions containing Br-dUMP for the energy of the X-rays.G values for these products were calculated on the basis of the absorbed energy. As the results, the ratios of G values of radiolytic products from Br-dUMP between X-rays of 13.49 keV and 13.43 keV were 2.2 for dUMP, 1.02 for Br-uracil and 1.23 for uracil, suggesting clearly the energy dependent enhancement. On the other hand, little significant difference between X-rays of 13.49 keV and 13.43 keV was observed for theG values of uracil released from dUMP irradiated in aqueous solutions. It seemed to confirm that the Auger electrons from K-shell of bromine atoms might play the main role for energy-dependent enhancement at induction of these radiolytic products.