Guo Yuxin, Lu Gonghao, Zhuo Jiezhen, Wang Jiayu, Li Xue, Zhang Zhiqiang
School of Chemical Engineering, University of Science and Technology Liaoning, 185 Qianshan Zhong Road, Anshan, Liaoning 114051, P. R. China.
J Mater Chem B. 2018 Apr 28;6(16):2489-2496. doi: 10.1039/c8tb00452h. Epub 2018 Apr 16.
We reported a visible-near-infrared fluorescent probe for peroxynitrite detection with large pseudo-Stokes and emission shifts, based on through-bond energy transfer (TBET) in combination with intramolecular charge transfer (ICT). Pyrene was chosen as a fluorophore (acceptor), which has monomer/excimer fluorescence characteristics. A conjugated 1,2-dimethylenehydrazine structure was a linker and phenyl boronate was selected as a reaction site (donor) to design the probe (Py-PhB) using the chemical transformation from boronate to phenol, which results in the increase of the energy of the donor to match the energy of the acceptor and simultaneously achieves TBET and ICT between the donor (phenolate) and the acceptor (pyrene), leading to a fluorescence 'OFF-ON' in a red-shifted region and a large emission shift. The results show that the probe exhibits high selectivity to ONOO with a detection limit of 3.54 μM. Favorable ICT from phenolate to pyrene makes the probe possess a large monomer emission shift (183 nm), red-shifted to organe-red light (598 nm). TBET ensures the probe with a large pseudo-Stokes shift of 244 nm. Furthermore, its excimer emits a near-infrared light (720 nm), which is extremely beneficial for bioimaging. In short, this probe offers a novel design strategy for designing the TBET fluorescent sensors emitting red or NIR light with large pseudo-Stokes and emission shifts.
我们报道了一种基于键间能量转移（TBET）与分子内电荷转移（ICT）相结合的用于检测过氧亚硝酸盐的可见-近红外荧光探针，该探针具有大的伪斯托克斯位移和发射光谱位移。芘被选作荧光团（受体），它具有单体/激基缔合物荧光特性。一个共轭的1,2-二亚甲基肼结构作为连接体，苯硼酸酯被选作反应位点（供体），通过硼酸酯到苯酚的化学转化来设计探针（Py-PhB），这导致供体能量增加以匹配受体能量，同时实现供体（酚盐）和受体（芘）之间的TBET和ICT，从而在红移区域产生荧光“关-开”以及大的发射光谱位移。结果表明，该探针对ONOO具有高选择性，检测限为3.54 μM。从酚盐到芘的有利ICT使得探针具有大的单体发射光谱位移（183 nm），红移至橙红色光（598 nm）。TBET确保探针具有244 nm的大伪斯托克斯位移。此外，其激基缔合物发射近红外光（720 nm），这对生物成像极为有利。简而言之，该探针为设计具有大伪斯托克斯位移和发射光谱位移的发射红色或近红外光的TBET荧光传感器提供了一种新颖的设计策略。
