Selective detections of Hg2+ and F− by using tailor-made fluorogenic probes

By ingeniously using a (imino)coumarin-precursor, three reactive fluorogenic probes of MP , FP, and FMP have been fabricated in a single facile synthetic route. MP and FP are able to respectively act as selective “turn-on” fluorescent probes for detecting Hg 2+ and F − in buffer solution via specific analyte-induced reactions. Linear ranges for the detection of Hg 2+ and F − are 0–10 μM and 0–100 μM with the limits of detection (LODs) of 4.0 × 10 −8  M and 1.14 × 10 −6  M (3δ/slope), respectively. FMP is able to work as a molecular “AND” logic gate-based fluorogenic probe for monitoring the coexistence of Hg 2+ and F − via a multistep reaction cascade. The analytes-induced sensing mechanisms have been determined by using high-performance liquid chromatography analysis (HPLC). In addition, three probes show negligible toxicity under the experimental conditions, and are successfully used for monitoring Hg 2+ and F − in living cells with good cell permeability. The success of the work demonstrates that ingenious utility of specific analyte-induced reactions and conventional concepts on the appropriate molecular scaffold can definitely deliver tailor-made probes for various intended sensing purposes.