An Anthracene-Based Hg Fluorescent Probe with Dithioacetal: Simple Synthesis, High Selectivity and Sensitivity, and Dual-Mode Detection Capability.

With the development of the chemical industry, the threat of mercury pollution to human health is increasing. Therefore, it is necessary to develop a low-cost, convenient and efficient Hg detection method. In this study, anthracene-based Hg fluorescent probes AN-2S and AN-4S were synthesized by a dithioacetal reaction for the rapid and efficient detection of the Hg concentration in water. Through molecular structure design and synthesis route optimization, the complexity and cost of the probe synthesis were greatly reduced. AN-2S and AN-4S had good water solubility, rapid response abilities and anti-interference abilities, and could specifically detect Hg using "turn-off" or "turn-on" detection modes within 1 min. The AN-4S probe showed a wide linear response range (040 μmol/L) and high sensitivity (4.93 × 10 mol/L) to Hg in 99% aqueous solutions, over a pH range of 513. The reaction mechanism between the probe and Hg was determined using 1H NMR and FT-IR spectra and Job's curves. It was proven that the AN-2S and AN-4S probes react with Hg in a molar ratio of 1:1 or 1:2. The dual-detection mode enabled the probes to be used not only for the accurate quantitative detection of Hg under a fluorescence spectrometer, but also for rapid qualitative analysis using a UV flashlight as a test strip, showing a broad practical application potential.