通过连接的spiropyran-anthraquinone分子进行光调节的跨膜电荷分离
Linyong Zhu1, Rafail F Khairutdinov, Jonathan L Cape
1Department of Chemistry, Washington State University, Pullman, Washington 99164-4630, USA.
Journal of the American Chemical Society
|January 19, 2006
概括
螺旋-氨基联体通过囊泡膜中介导光驱动的电子转移,其效率受到染料异构和氧化还原载体扩散的影响. 这个过程将光能转化为化学潜力.
科学领域:
- 摄影化学的使用.
- 超分子化学 超分子化学
- 膜生物物理学 膜生物物理学
背景情况:
- 人工光合作用旨在将光能转化为化学能.
- 囊泡系统用于模仿细胞膜,用于研究运输现象.
- 螺旋-氨基联体提供可调节的氧化还原和光色特性.
研究的目的:
- 为了研究通过螺旋-氨基 (SP-AQ) 结合物的跨膜电子转移的调解.
- 了解SP-AQ光异构化对反应量子产量和机制的影响.
- 为了阐明光敏化氧化还原反应在囊泡中的能量和动力学.
主要方法:
- 使用了含有封闭的三二里丁复合体 (Co(bpy) 3 ((3+)) 的单基酸丁胆囊.
- 采用ZnTPPS(4-) 光敏化和外部EDTA作为减光剂.
- 应用过渡光谱学,光火和光解下的运动分析.
主要成果:
- 通过SP-AQ合物中介的ZnTPPS(4-) 光敏化减少了内部Co(bpy) 3(3+).
- 斯皮洛普兰的光异构化到梅罗氨酸显著降低了量子产量 (3至6倍).
- 降低的产量归因于增强的光灭和较慢的merocyanine物种的跨膜扩散.
- 已识别的反应中间体,包括半农基.
- 证明了SP-AQ的电中性跨膜氧化还原,与其他子的电生成途径形成鲜明对比.
结论:
- 螺旋 - antraquinone 染料的同位体状态极大地影响了跨膜电子转移效率.
- 光异构化引起的光物理性质变化和载体流动性决定了整体量子产量.
- 该SP-AQ系统通过拟议的氧化火和共同传输机制将光子能量转化为化学和电化学潜力.
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