Laboratory of Functional Molecular Solids, Ministry of Education, College of Chemistry and Material Science, Anhui Normal University, Wuhu, 241000, People's Republic of China.
Methods Appl Fluoresc. 2017 Jun 15;5(2):024015. doi: 10.1088/2050-6120/aa7170.
Simple quinoline-based fluorescent probes for Fe have been efficiently synthesized through 'click' reaction. Both probes gave intense fluorescence compared to 8-hydroquinoline in various organic solvents due to the inhibition of the excited state intramolecular photon transfer process, while showing dramatically quenched and red-shifted fluorescence in an aqueous solution, which can be attributed to the hydrogen bond-induced intermolecular excited state proton transfer process. In the presence of Fe or in an acidic condition (pH less than 4.0), both probes showed similar quenching of the emission and over 100 nm red-shifts of their emission maxima. The binding mode between the probes and Fe has been found to be 1:1 based on Job's plot. A highly sensitive and selective response in their absorption and emission towards Fe over many other metal ions, including Cr and Cu, was observed and may be the result of the ground state metal to ligand charge transfer effect from Fe to quinoline ligands.
已通过“点击”反应高效合成了简单的基于喹啉的荧光探针用于检测 Fe。与 8-羟基喹啉相比，由于抑制了激发态分子内光子转移过程，两种探针在各种有机溶剂中均表现出强烈的荧光，而在水溶液中则显示出荧光显著猝灭和红移，这归因于氢键诱导的分子间激发态质子转移过程。在存在 Fe 或在酸性条件（pH 小于 4.0）下，两种探针的发射均表现出相似的猝灭，且发射峰发生超过 100nm 的红移。根据 Job 图发现探针与 Fe 的结合模式为 1:1。观察到探针对 Fe 的吸收和发射具有高度灵敏和选择性的响应，而对许多其他金属离子，包括 Cr 和 Cu 则没有响应，这可能是由于从 Fe 到喹啉配体的基态金属到配体电荷转移效应所致。
