Center for Design and Applications of Molecular Catalysts, Department of Chemistry and Chemical Engineering, Inha University, Incheon, 402-751, South Korea.
Analyst. 2018 Oct 22;143(21):5285-5294. doi: 10.1039/c8an01221k.
The development of a fluorescence method for the selective ratiometric detection of Al3+ ions in pure aqueous solutions and live cells is still a significant challenge. In the present study, we synthesized a new type of fluorescent probe using an Al3+-triggered self-assembly based on the dipeptide receptor and an aggregation-induced emission fluorophore. The fluorescent probe (1) bearing cyanostilbene with excitation by visible light detected Al3+ ions sensitively in pure aqueous buffered solution by ratiometric red-emission at 600 nm. 1 provided a highly selective ratiometric detection of Al3+ among 16 metal ions in aqueous solution. 1 exhibited sensitive ratiometric response to Al3+ in aqueous buffered solutions at pH ranging from 5 to 7.4. The detection limit (145 nM, R2 = 0.999) for Al3+ ions in pure aqueous solution was much lower than the maximum allowable level of Al3+ in drinking water demanded by the Environmental Protection Agency (EPA). The probe provided an efficient approach to detect low concentrations of Al3+ in ground water, tap water, and live cells by ratiometric red-emissions at 600 nm. The binding study using dynamic light scattering, NMR, IR, and TEM revealed that the complex between 1 and Al3+ self-assembled to form nanoparticles, resulting in the enhancement of the emission at 600 nm and a concomitant decrease in the emission at 535 nm.
在纯水溶液和活细胞中选择性比率检测 Al3+离子的荧光方法的发展仍然是一个重大挑战。在本研究中，我们使用基于二肽受体和聚集诱导发射荧光团的 Al3+触发自组装合成了一种新型荧光探针。带有氰基苯乙烯的荧光探针（1）通过可见光激发，在纯缓冲水溶液中通过 600nm 处的比率红发射灵敏地检测到 Al3+离子。1 在水溶液中对 16 种金属离子具有高度选择性的比率检测 Al3+。1 在 pH 值为 5 至 7.4 的缓冲水溶液中对 Al3+表现出灵敏的比率响应。在纯水溶液中，Al3+离子的检测限（145 nM，R2 = 0.999）远低于环境保护署（EPA）要求的饮用水中 Al3+的最大允许水平。探针通过在 600nm 处的比率红发射提供了一种有效的方法来检测地下水、自来水和活细胞中低浓度的 Al3+。使用动态光散射、NMR、IR 和 TEM 的结合研究表明，1 与 Al3+之间的复合物自组装形成纳米粒子，导致 600nm 处的发射增强，同时 535nm 处的发射减少。
