论文标题
水是电离吡咯的辐射保护剂
Water is a radiation protection agent for ionised pyrrole
论文作者
论文摘要
辐射引起的生物物质损害本质上是一个普遍存在的问题。水合环境的影响得到了广泛讨论，但其确切的作用仍然难以捉摸。利用定义明确的溶剂分子聚集体，我们在实验上观察到了氢键的水分子，该水分子充当电离吡咯（一种原型芳族芳族生物分子）的辐射保护剂。吡咯和吡咯（H $ _2 $ O）的纯样品是外部离子化的，并研究了随后的损坏和放松过程。裸吡咯离子通过C-C或N-C共价键的破裂而碎裂。但是，对于吡咯（H $ _2 $ O）$^+$，我们观察到通过中性水的解离释放或通过将电子或质子传递到整个氢键中，对吡咯环进行了强烈保护。总体而言，单个水分子强烈降低了碎裂概率，从而大大降低了单离子吡咯的持续辐射损伤。
Radiation-induced damage of biological matter is an ubiquitous problem in nature. The influence of the hydration environment is widely discussed, but its exact role remains elusive. Utilising well defined solvated-molecule aggregates, we experimentally observed a hydrogen-bonded water molecule acting as a radiation protection agent for ionised pyrrole, a prototypical aromatic biomolecule. Pure samples of pyrrole and pyrrole(H$_2$O) were outer-valence ionised and the subsequent damage and relaxation processes were studied. Bare pyrrole ions fragmented through the breaking of C-C or N-C covalent bonds. However, for pyrrole(H$_2$O)$^+$, we observed a strong protection of the pyrrole ring through the dissociative release of neutral water or by transferring an electron or proton across the hydrogen bond. Overall, a single water molecule strongly reduces the fragmentation probability and thus the persistent radiation damage of singly-ionised pyrrole.
