在 antraquinone-DNA 合物中超快单元和三元电荷转移的动力学
Frederick D Lewis1, Arun K Thazhathveetil, Tarek A Zeidan
1Department of Chemistry and Argonne-Northwestern Solar Energy Research Center, Northwestern University, Evanston, Illinois 60208-3113, USA. fdl@northwestern.edu
Journal of the American Chemical Society
|December 24, 2009
概括
单电荷分离在DNA - antraquinone 合物中比三重电荷形成更有效. 与腺因相比,关氨酸基加速电荷分离和重组.
科学领域:
- 摄影化学的使用.
- 分子生物物理学 分子生物物理学
- 材料科学 材料科学 材料科学
背景情况:
- 对于理解电荷转移过程而言,DNA-氨酸合物至关重要.
- 激进的离子对动力学是DNA光化学和损伤的基础.
研究的目的:
- 研究单基和三基基的离子对形成效率.
- 确定DNA-氨基系统中的电荷重组动态.
- 阐明 purin 基 (瓜氨酸与腺氨酸) 对这些过程的影响.
主要方法:
- 采用5秒时间解析的短暂吸收光谱法.
- 这种技术可以进行超快的动态测量.
主要成果:
- 单一电荷分离比跨系统交叉到三重电荷状态更有效.
- 因此,形成长寿命的三重基离子对是低效的.
- 电荷重组和分离与关氨酸相比,作为邻近的纯氨酸基的腺氨酸更快.
结论:
- DNA - antraquinone 结合物的电子特性有利于单电荷分离.
- 邻近的纯素基的身份显著影响了电荷转移动力学.
- 了解这些动态是设计基于DNA的新型功能材料的关键.
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