A spectroscopic survey of substituted indoles reveals consequences of a stabilized 1Lb transition.
A spectroscopic survey of substituted indoles reveals consequences of a stabilized 1Lb transition.
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DOI：
10.1111/j.1751-1097.2012.01219.x
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发表时间：
2013-01
影响因子：
3.3
通讯作者：
Juszczak LJ
中科院分区：
文献类型：
--
作者：
Meng X;Harricharran T;Juszczak LJ
尽管色氨酸是蛋白质结构的天然探针，但由于存在两个电子跃迁 1La 和 1Lb，其荧光发射光谱的解释变得复杂。理论计算表明，邻近吲哚环的点电荷可以改变发射最大值。本研究通过吸收光谱和荧光光谱以及各向异性和寿命测量探讨了吡咯和苄基环取代对跃迁能量的影响。对吲哚衍生物的研究表明，吡咯环上的甲基取代会同时影响 1La 和 1Lb 能量，而亲电基团的苄基取代会提升 1La/1Lb 简并性。对于环己烷中的 5- 和 6-羟基吲哚，可解析 1La 和 1Lb 跃迁。这一发现为吲哚蒸气的吸收和激发光谱中的 1La 原点指定提供了依据。 5- 和 6- 羟基吲哚激发光谱表明，尽管发射光谱发生蓝移，但 1La 和 1Lb 跃迁均有助于发射。 5-羟基吲哚的 10 0 ns 荧光寿命与电荷受体诱导的非辐射速率增加一致。
Although tryptophan is a natural probe of protein structure, interpretation of its fluorescence emission spectrum is complicated by the presence of two electronic transitions, 1La and 1Lb. Theoretical calculations show that a point charge adjacent to either ring of the indole can shift the emission maximum. This study explores the effect of pyrrole and benzyl ring substitutions on the transitions’ energy via absorption and fluorescence spectroscopy, and anisotropy and lifetime measurements. The survey of indole derivatives shows that methyl substitutions on the pyrrole ring effect 1La and 1Lb energies in tandem while benzyl ring substitutions with electrophilic groups lift the 1La/1Lb degeneracy. For 5- and 6-hydroxyindole in cyclohexane, 1La and 1Lb transitions are resolved. This finding provides for 1La origin assignment in the absorption and excitation spectra for indole vapor. The 5- and 6-hydroxyindole excitation spectra show that despite a blue-shifted emission spectrum, both the 1La and 1Lb transitions contribute to emission. 10 0 ns fluorescence lifetimes for 5-hydroxyindole are consistent with a charge acceptor-induced increase in the nonradiative rate.
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影响因子：
3.3
作者：
Pan, Chia-Pin;Muino, Pedro L.;Callis, Patrik R.
通讯作者：
Callis, Patrik R.
影响因子：
3.3
作者：
Robinson, David;Besley, Nicholas A.;Hirst, Jonathan D.
通讯作者：
Hirst, Jonathan D.
影响因子：
16.6
作者：
Broos, Jaap;Tveen-Jensen, Karina;Callis, Patrik R.
通讯作者：
Callis, Patrik R.
影响因子：
3.3
作者：
Pan, CP;Callis, PR;Barkley, MD
通讯作者：
Barkley, MD
影响因子：
3.1
作者：
Lotte, K;Plessow, R;Brockhinke, A
通讯作者：
Brockhinke, A