B.I. Stepanov's Institute of Physics, National Academy of Sciences of Belarus, Nezavisimosti ave. 68, 220072, Minsk, Belarus.
Photochem Photobiol Sci. 2009 Oct;8(10):1448-54. doi: 10.1039/b9pp00016j. Epub 2009 Aug 7.
The photophysics of free pyrenedicarboxamide (Py-DCA) in solution as well as of single-stranded and double-stranded oligonucleotides (ss and ds ONs) containing 1-7 pyrene building blocks per strand were studied by steady-state and time-resolved fluorescence spectroscopy. It was found that the fluorescence quantum yield Phi(F) of free Py-DCA chromophore in solution is rather high (Phi(F) = 0.44). However, after incorporation of the chromophore into a ss ON the monomeric chromophore fluorescence is quenched more than 40-fold due to electron-transfer reactions with ON bases. An increase of the number n of neighboring pyrenes in an ON results in Phi(F) growth up to 0.25 at n = 6. Starting from n = 2, all fluorescence belongs mainly to excimer formed by pyrene chromophores. Sections composed of multiple pyrenes may be considered as robust functional entities that may serve as independent modules in DNA-based, functional nano-architectures.
研究了游离的并苯二酰胺（Py-DCA）在溶液中的光物理性质，以及含有 1-7 个并苯构建单元的单链和双链寡核苷酸（ss 和 ds ON）的光物理性质，采用稳态和时间分辨荧光光谱法进行了研究。结果发现，游离的 Py-DCA 发色团在溶液中的荧光量子产率 Phi(F)相当高（Phi(F) = 0.44）。然而，将发色团掺入 ss ON 后，由于与 ON 碱基的电子转移反应，单体发色团的荧光猝灭超过 40 倍。在 ON 中相邻的并苯数量 n 的增加导致 Phi(F) 增长至 0.25，当 n = 6 时。从 n = 2 开始，所有荧光主要属于由并苯发色团形成的激基复合物。由多个并苯组成的部分可以被认为是稳健的功能实体，它们可以作为基于 DNA 的功能纳米结构中的独立模块。
