Perylenemonoimide-Based Colorimetric Probe with High Contrast for Naked-Eye Detection of Fluoride Ions
Mengxin Mu, Xin Ke, Wenyu Cheng, Jie Li, Chendong Ji, Meizhen Yin
Abstract
Excessive fluoride ions (F–) in drinking water are harmful to the environment and human health. However, most reported probes of F– can only detect fluorocarbons rather than aqueous F–. Herein, a colorimetric and fluorescent probe (PMI-OH) based on perylenemonoimide is designed and synthesized for the detection of aqueous F–, with high sensitivity, good selectivity, and reversibility. The F– causes deprotonation of PMI-OH, leading to a significant red shift of 222 nm (from 520 to 742 nm) of the absorption band. Upon the addition of fluorocarbons, the fluorescence intensities of PMI-OH show good linearity against the concentrations of F–, realizing the quantitative detection of fluorocarbons with a limit of detection as low as 0.495 μM. Finally, PMI-OH is applied to detect F– in drinking water. The color of PMI-OH solution shows remarkable response from pink to green when the concentrations of F– exceed the upper limit set by the World Health Organization (WHO), realizing rapid and naked-eye detection of aqueous F–.