Departamento de Química, Instituto de Tecnología Química UPV-CSIC, Universitat Politècnica de València, 46022 Valencia, Spain.
Université Paris-Saclay, CEA, CNRS, LIDYL, 91191 Gif-sur-Yvette, France.
Molecules. 2022 May 31;27(11):3558. doi: 10.3390/molecules27113558.
The publication deals with polymeric pA●pT and oligomeric A●T DNA duplexes whose fluorescence is studied by time-correlated single photon counting. It is shown that their emission on the nanosecond timescale is largely dominated by high-energy components peaking at a wavelength shorter than 305 nm. Because of their anisotropy (0.02) and their sensitivity to base stacking, modulated by the duplex size and the ionic strength of the solution, these components are attributed to mixed ππ*/charge transfer excitons. As high-energy long-lived excited states may be responsible for photochemical reactions, their identification via theoretical studies is an important challenge.
本文研究了聚合的 pA●pT 和寡聚 A●T DNA 双链体，通过时间相关单光子计数法研究了它们的荧光。结果表明，它们在纳秒时间尺度上的发射主要由高能成分主导，这些成分的峰值波长短于 305nm。由于它们的各向异性（0.02）和对碱基堆积的敏感性，这些成分受双链体大小和溶液离子强度的调制，被归因于混合的 ππ*/电荷转移激子。由于高能长寿命激发态可能导致光化学反应，因此通过理论研究来识别它们是一个重要的挑战。
