Wang Feiyi, Zhou Li, Zhao Chunchang, Wang Rui, Fei Qiang, Luo Sihang, Guo Zhiqian, Tian He, Zhu Wei-Hong
Key Laboratory for Advanced Materials and Institute of Fine Chemicals , Shanghai Key Laboratory of Functional Materials Chemistry , Collaborative Innovation Center for Coal Based Energy (i-CCE) , East China University of Science & Technology , Shanghai 200237 , P. R. China . Email:
Shanghai Key Laboratory of New Drug Design , School of Pharmacy , East China University of Science & Technology , Shanghai 200237 , P. R. China.
Chem Sci. 2015 Apr 1;6(4):2584-2589. doi: 10.1039/c5sc00216h. Epub 2015 Feb 18.
monitoring of intracellular thiol activity in cell growth and function is highly desirable. However, the discriminative detection of glutathione (GSH) from cysteine (Cys) and homocystein (Hcy) and from common amino acids still remains a challenge due to the similar reactivity of the thiol groups in these amino acids. Here we report a novel strategy for selectively sensing GSH by a dual-response mechanism. Integrating two independent reaction sites with a disulfide linker and a thioether function into a fluorescent BODIPY-based chemsensor can guarantee the synergetic dual-response in an elegant fashion to address the discrimination of GSH. In the first synergetic reaction process, the thiol group in GSH, Cys and Hcy induces disulfide cleavage and subsequent intramolecular cyclization to release the unmasked phenol-based BODIPY (). In the second synergetic process, upon the substitution of the thioether with the nucleophilic thiolate to form a sulfenyl-BODIPY, only the amino groups of Cys and Hcy, but not that of GSH, undergo a further intramolecular displacement to yield an amino-substituted BODIPY. In this way, we make full use of the kinetically favorable cyclic transition state in the intramolecular rearrangement, and enable photophysical distinction between sulfenyl- and amino-substituted BODIPY for allowing and under physiological conditions. Moreover, this probe exhibits a distinguishable ratiometric fluorescence pattern generated from the orange imaging channel to the red channel, which proves the differentiation of GSH from Cys and Hcy in living cells.
监测细胞生长和功能中的细胞内硫醇活性是非常有必要的。然而,由于这些氨基酸中硫醇基团的反应性相似,从半胱氨酸(Cys)、同型半胱氨酸(Hcy)以及常见氨基酸中鉴别检测谷胱甘肽(GSH)仍然是一个挑战。在此,我们报道了一种通过双响应机制选择性传感GSH的新策略。将具有二硫键连接子和硫醚功能的两个独立反应位点整合到基于荧光硼二吡咯的化学传感器中,能够以一种巧妙的方式保证协同双响应,以解决GSH的鉴别问题。在第一个协同反应过程中,GSH、Cys和Hcy中的硫醇基团诱导二硫键断裂并随后发生分子内环化,从而释放出未被掩盖的基于苯酚的硼二吡咯()。在第二个协同过程中,硫醚被亲核硫醇盐取代形成亚磺酰基 - 硼二吡咯时,只有Cys和Hcy的氨基,而不是GSH的氨基,会发生进一步的分子内取代反应,生成氨基取代的硼二吡咯。通过这种方式,我们充分利用了分子内重排中动力学有利的环状过渡态,并实现了亚磺酰基取代和氨基取代硼二吡咯之间的光物理区分,从而在生理条件下实现了 和 。此外,该探针在橙色成像通道到红色通道之间呈现出可区分的比率荧光模式,这证明了在活细胞中GSH与Cys和Hcy的区分。