Positive and negative ion formation via slow electron collisions with 5-bromouridine
Positive and negative ion formation via slow electron collisions with 5-bromouridine
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DOI：
10.1140/epjd/e2005-00205-7
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发表时间：
2005-08-01
影响因子：
1.8
通讯作者：
Scheier, P
中科院分区：
文献类型：
--
作者：
Denifl, S;Candori, P;Scheier, P
利用交叉电子束/中性束与四极质谱计相结合的方法，研究了低能电子与5-溴代吡啶(BrUrd)非弹性低能电子相互作用的阳离子和阴离子的形成。BrUrd分子属于辐射增敏剂，可以增加DNA(或RNA)对电离辐射的敏感性。在正离子形成的情况下，在阈值附近测量了电离效率曲线，并用非线性最小二乘拟合法确定了相应的出现能。在电子能量约为0-14 eV的范围内，研究了阴离子产额。从对负离子和正离子的现有结果的比较中，推断出有关辐射增敏剂的潜在机制的信息。
Cation and anion formation is studied experimentally upon inelastic low energy electron interactions with 5-bromouridine (BrUrd) using a crossed electron/neutral beams set-up combined with a quadrupole mass spectrometer. The BrUrd molecule belongs to the class of radiosensitizers that increase the sensitivity of DNA (or RNA) to ionizing radiation. In the case of positive ion formation the ionization efficiency curves are measured near the threshold and the corresponding appearance energies are determined using a non-linear least square fitting procedure. The anion yields are investigated in the electron energy range from about 0 to 14 eV. From the comparison of the present results for negative and positive ions information concerning the underlying mechanism of radiosensitizers is deduced.