A new fluorescent probe based on quinoline for detection of Al3+ and Fe3+ with “off–on–off” response in aqueous solution

摘要

A new quinoline-based fluorescent probe 1 has been designed and synthesized. Fluorescence emission spectra of the probe showed red-shift and obvious enhancement of fluorescent intensity upon the addition of Al ~(3+) (turn-on). 1 –Al ~(3+) showed high selectivity for Fe ~(3+) over other metal ions, and eliminated the interference of Al ~(3+) during Fe ~(3+) detection (turn-off). It showed highly selective relay recognition of Al ~(3+) and Fe ~(3+) via a fluorescence “off–on–off” mechanism. Fluorescence spectra indicated that the response of 1 –Al ~(3+) to Fe ~(3+) was caused by central metal displacement. The detection limits for the analysis of Al ~(3+) and 1 –Al ~(3+) –Fe ~(3+) ions were calculated to be 2.20 × 10 ~(?6) M and 1.96 × 10 ~(?5) M, respectively. Living HeLa cell imaging studies revealed that the probe was cell-permeable and it could be used to detect intracellular Al ~(3+) and Fe ~(3+) ions.