通过化学诱导的动态核极化测量,探索聚芳Ru (II) 复合物和生物分子之间的光反应
Sandrine Perrier1, Epiphanie Mugeniwabagara, Andrée Kirsch-De Mesmaeker
1Laboratoire de Résonance Magnétique Nucléaire Haute Résolution, Université Libre de Bruxelles, 50 Av. F.D. Roosevelt, B-1050 Bruxelles, Belgium.
Journal of the American Chemical Society
|August 8, 2009
概括
这项研究报告了光化学诱导的动态核极化 (CIDNP) 对于多芳香的 (Ruthenium) 复合体. 这些复合物促进光氧化,并使其与生物分子相互作用的新研究成为可能.
科学领域:
- 摄影化学的使用
- 核磁共振光谱学 核磁共振光谱学
- 协调化学 协调化学
背景情况:
- ((II) 复合物与多芳合体被研究了它们的光化学特性.
- 光化学诱导的动态核极化 (CIDNP) 是研究激素中间体的一种敏感技术.
- 了解这些复合体中的光电子转移过程对于它们的应用至关重要.
研究的目的:
- 调查光-CIDNP在多芳香的Ru (II) 复合体中的发生和特征.
- 探索涉及这些复杂物和生物分子的光电子转移机制.
- 评估光-CIDNP在研究Ru (II) 复合物和生物分子之间的相互作用方面的潜力.
主要方法:
- 稳定状态 (1) H 光 CIDNP 实验在 14.1 T 进行.
- 使用了[Ru() ((3)) ] ((2+),[Ru() ((2))) ] ((2+) 和[Ru() ((3) ] ((2+) 的脱氧水溶液.
- 实验是在瓜诺辛-5'-单酸盐或N-乙提洛辛的存在下进行的.
主要成果:
- 对于[Ru(tap) ((3))) ((2+) 和[Ru(tap) ((2))) ((phen) ((2+) ],观察到光CIDNP,这表明光电子转移,但对于[Ru(phen) ((3))) ((2+) 则没有.
- 检测到高极化增强 (高达60%) 的特定核 (H-2和H-7) 的龙头配体,表明显著的未配对电子密度.
- 长寿基性物种的积累被记录在[Ru(tap)(3)](2+),导致信号扩大和CIDNP灭绝.
结论:
- 这项研究首次证明,光-CIDNP是由多芳Ru (II) 复合物的光氧化产生的.
- 这些结果与光电子转移相一致,涉及接联体和生物分子的光添加物形成.
- 照片-CIDNP为研究多芳香的Ru (II) 复合物及其与生物系统的相互作用提供了新的途径.
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