量子点光灭途径与Cr (III) 复合体. 通过转Cr () () (ONO) 2+产生光敏感的NO
Daniel Neuman1, Alexis D Ostrowski, Alexander A Mikhailovsky
1Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, California 93106-9510, USA.
Journal of the American Chemical Society
|December 14, 2007
概括
这项研究探讨了 (III) 复合体如何与量子点 (QD) 相互作用. 研究人员发现,这些复合物可以灭QD光辐射,其中一些使光敏感氧化释放.
科学领域:
- 材料科学 材料科学 材料科学
- 摄影化学的使用.
- 纳米技术 纳米技术
背景情况:
- 溶于水的硫化/硫化 (CdSe/ZnS) 核心/外量子点 (QDs) 呈现光发光 (PL).
- (III) 复合物,特别是跨-Cr (cyclam) Cl2+,跨-Cr (cyclam) ONO2+和跨-Cr (cyclam) CN2+,正在研究它们与QDs的相互作用.
研究的目的:
- 为了研究由 (III) 复合体对 QD 光发光的干扰.
- 从过渡金属中心评估QD作为生物活性分子光敏感释放的天线,例如氧化 (NO).
主要方法:
- 光发光 (PL) 光谱法用于观察排放火.
- 时间解析的PL和吸收光谱被用来研究超快的动态.
- 研究了福斯特共振能量转移 (FRET) 和电荷转移机制.
主要成果:
- 超-Cr ()Cl2+和超-Cr ()Cl2+导致度依赖的QD频段边缘辐射火,而超-Cr ()Cl2+的影响很小.
- 通过跨-Cr ((cyclam) Cl2+的火被KCl减弱,这表明Cr ((III) 离子和负电荷的QD表面之间存在静电组合.
- 观察到光敏感的NO释放与跨-Cr ((cyclam) ((ONO) 2+一起,这是已知的NO前体,同时灭了带边和红移陷排放.
结论:
- 波段边缘PL火被归因于FRET从QD到表面结合 (III) 复合体.
- 低能陷排放灭通过电荷转移通路发生.
- 这项研究证明了QD作为光敏释放应用中的天线的潜力.
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