Department of Chemistry, Renmin University of China, Beijing 100872, China.
J Phys Chem B. 2011 May 5;115(17):5001-7. doi: 10.1021/jp200876d. Epub 2011 Apr 8.
Atto655 has been widely used as an excellent probing dye through photoinduced electron transfer (PET) for biochemical processes in oligonucleotides or polypeptides. However, its photophysical properties in the presence of the quenchers guanosine and tryptophan have not been carefully studied. In this work, we investigated the dynamics of PET between Atto655 and the two quenchers in aqueous solution with femtosecond transient absorption experiments. We derived that the charge separation rate is 8.1 × 10(9) s(-1) and the charge recombination rate is 7.7 × 10(10) s(-1) for the collision complex between Atto655 and guanosine and that the corresponding values for the collision complex between Atto655 and tryptophan are 4.0 × 10(11) and 5.0 × 10(12) s(-1), respectively. These experimental results are quite consistent with the prediction of Marcus-type theory for electron transfer. The implications of this work for the data analysis of PET-based fluorescence correlation spectroscopy are discussed.
Atto655 已被广泛用作通过光诱导电子转移（PET）在寡核苷酸或多肽中的生化过程的优异探测染料。然而，其在猝灭剂鸟嘌呤和色氨酸存在下的光物理性质尚未得到仔细研究。在这项工作中，我们通过飞秒瞬态吸收实验研究了 Atto655 与两种猝灭剂在水溶液中的 PET 动力学。我们得出结论，对于 Atto655 与鸟嘌呤的碰撞复合物，电荷分离速率为 8.1×10(9)s(-1)，电荷复合速率为 7.7×10(10)s(-1)，而对于 Atto655 与色氨酸的碰撞复合物，相应的值分别为 4.0×10(11)和 5.0×10(12)s(-1)。这些实验结果与电子转移的 Marcus 型理论的预测非常一致。本文对基于 PET 的荧光相关光谱数据分析的影响进行了讨论。
