Trojanowski P, Plötner J, Grünewald C, Graupner F F, Slavov C, Reuss A J, Braun M, Engels J W, Wachtveitl J
Institute for Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue-Straße 7, 60438 Frankfurt/Main, Germany.
Phys Chem Chem Phys. 2014 Jul 21;16(27):13875-88. doi: 10.1039/c4cp01148a. Epub 2014 Jun 4.
The photo-physical properties of 2-(1-ethynylpyrene)-adenosine (PyA), a fluorescent probe for RNA dynamics, were examined by solvation studies. The excited-state dynamics display the influence of the vicinity on the spectral features. Combining improved transient absorption and streak camera measurements along with a new analysis method provide a detailed molecular picture of the photophysics. After intramolecular vibrational energy redistribution (IVR), two distinct states are observed. Solvent class (protic/aprotic) and permittivity strongly affect the properties of these states and their population ratio. As a result their emission spectrum is altered, while the fluorescence quantum yield and the overall lifetime remain nearly unchanged. Consequently, the hitherto existing model of the photophysics is herein refined and extended. The findings can serve as basis for improving the information content of measurements with PyA as a label in RNA.
通过溶剂化研究考察了用于RNA动力学的荧光探针2-(1-乙炔基芘)-腺苷（PyA）的光物理性质。激发态动力学显示了周围环境对光谱特征的影响。结合改进的瞬态吸收和条纹相机测量以及一种新的分析方法，提供了光物理过程的详细分子图景。在分子内振动能量重新分布（IVR）之后，观察到两种不同的状态。溶剂类型（质子性/非质子性）和介电常数强烈影响这些状态的性质及其布居比。结果，其发射光谱发生改变，而荧光量子产率和整体寿命几乎保持不变。因此，本文对迄今已有的光物理模型进行了完善和扩展。这些发现可为提高以PyA作为RNA标记的测量的信息含量提供依据。
