State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China.
Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China.
Molecules. 2023 Jul 7;28(13):5269. doi: 10.3390/molecules28135269.
Benzo[a]pyrene is a widespread environmental pollutant and a strong carcinogen. It is important to understand its bio-toxicity and degradation mechanism. Herein, we studied the excited state dynamics of benzo[a]pyrene by using time-resolved fluorescence and transient absorption spectroscopic techniques. For the first time, it is identified that benzo[a]pyrene in its singlet excited state could react with oxygen, resulting in fluorescence quenching. Additionally, effective intersystem crossing can occur from its singlet state to the triplet state. Furthermore, the interaction between the excited benzo[a]pyrene and ct-DNA can be observed directly and charge transfer between benzo[a]pyrene and ct-DNA may be the reason. These results lay a foundation for further understanding of the carcinogenic mechanism of benzo[a]pyrene and provide insight into the photo-degradation mechanism of this molecule.
苯并[a]芘是一种广泛存在的环境污染物和强致癌物。了解其生物毒性和降解机制非常重要。在这里，我们通过使用时间分辨荧光和瞬态吸收光谱技术研究了苯并[a]芘的激发态动力学。首次确定，苯并[a]芘在其单重激发态时可以与氧反应，导致荧光猝灭。此外，有效电子从单重态到三重态的系间窜越也可以发生。此外，还可以直接观察到激发态苯并[a]芘与 ct-DNA 的相互作用，并且苯并[a]芘和 ct-DNA 之间的电荷转移可能是其原因。这些结果为进一步了解苯并[a]芘的致癌机制奠定了基础，并为该分子的光降解机制提供了深入的了解。
