Ultrafast electron - transfer reactions in radiation chemistry and radiation biology

这项更新建议描述了一项持续研究计划，以研究具有生物和环境意义的分子系统中的超快电子转移反应。在过去的几年里，申请人建立了一个创新的计划，研究各种分子系统的超快电子转移反应，并发现它们对环境和生物过程的重要性，范围从大气臭氧消耗到抗癌药物治疗癌症的作用机制。这项提议的目的是实时观察被认为是环境污染物的有机卤素分子在电离/紫外线辐射下在生物和环境系统中的超快电子转移反应，并评估其生物学效应。申请人建立了一种高灵敏度的飞秒(超快)时间分辨激光光谱学，它对于实时、直接观察有机卤素分子在水环境中的超快电子转移反应非常强大。这是通过在分子水平上实时观察化学反应而提供的非凡机会。拟议的研究将利用新的超快激光光谱技术，并结合生物分析方法，如DNA损伤和细胞死亡分析。该项目将对了解有机卤素污染物的分子反应机理及其对地球环境和人类健康的影响具有重要意义。此外，这项工作中开发的反应机理可能会导致发现用于保护暴露在有机卤素和辐射中的人类的分子试剂，并开发一种有效和经济的处置环境有害有机卤素材料的技术。

This renewal proposal describes a continuous research program to study ultrafast electron-transfer reactions in molecular systems of biological and environmental significance. Over the past several years, the applicant has built an innovative program to study ultrafast electron-transfer reactions of various molecular systems and to discover their importance for environmental and biological processes, ranging from atmospheric ozone depletion to the mechanisms of action of anticancer drugs for cancer treatment. The objectives of this proposal are to obtain real-time observations of ultrafast electron transfer reactions of organohalogen molecules, recognized as environmental pollutants, in biological and environmental systems under ionizing/UV radiation and to evaluate their biological effects. The applicant has built a high-sensitivity femtosecond (ultrafast) time-resolved laser spectroscopy, which is very powerful for real-time, direct observation of ultrafast electron-transfer reactions of organohalogen molecules in an aqueous environment. This is the remarkable opportunity afforded through the real-time observation of chemical reactions at the molecular level. The proposed research will utilize the novel ultrafast laser spectroscopic technique combined with biological analysis methods such as DNA damage and cell death assays. This project will have significance for understanding the molecular reaction mechanisms of organohalogen pollutants and their effects on Earth's environment and human health. Moreover, the reaction mechanism developed in this work may lead to the discovery of molecular agents for protection of humans exposed to organohalogens and radiation and the development of an efficient and economical technology for disposal of environmentally hazardous organohalogen materials.