微环境对Pd-bacteriopheophorbide产生反应性氧物种的影响
Yahel Vakrat-Haglili1, Lev Weiner, Vlad Brumfeld
1Department of Plant Sciences, Weizmann Institute of Science, Rehovot, Israel.
Journal of the American Chemical Society
|April 28, 2005
概括
环境显著影响光动力疗法 (PDT) 染料的反应性氧物种 (ROS) 生产. 在水和有机环境中,Pd-bacteriopheophorbide会产生不同的ROS,这会影响PDT的疗效.
科学领域:
- 摄影化学的使用.
- 生物物理学的生物物理.
- 药用化学 医学化学
背景情况:
- 活性氧物种 (ROS) 在生物过程和光动力学疗法 (PDT) 中至关重要.
- 染料的环境会影响在PDT过程中ROS的产生和有效性.
- 一种针对血管的PDT剂 (WST09/TOOKAD) Pd-bacteriopheophorbide (Pd-Bpheid) 正在临床试验中.
研究的目的:
- 研究染料的环境如何影响Pd-Bpheid.产生的ROS的产量,命运和有效性.
- 阐明不同介质中ROS形成的机制.
主要方法:
- 具有时间分辨率的光谱仪 (pico和nanosecond)
- 电子自旋共振 (ESR) 光谱与自旋陷.
- 时间解析的单点氧光.
- 化学产品分析 化学产品分析
主要成果:
- 在水性介质中,Pd-Bpheid会产生基基,超氧基和过氧化.
- 在有机溶剂中,Pd-Bpheid 完全形成单氧.
- 单片氧量子产量从有机溶剂中的1~降至膜状系统 (菌体,脂质体) 的0.5~.
- 在膜状系统中,超氧化和基激素的量子产率为0.1%.
- 激素形成涉及从膜/水界面激发的Pd-Bpheid转移电子和质子.
结论:
- 环境极大地控制了Pd-Bpheid产生的ROS,影响了PDT的结果.
- 在近红外 (NIR) 中产生ROS的细菌基衍生物为PDT和氧化还原调节研究提供了新的可能性.
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