Hg2+ induced hydrolysis of thiazole amine based Schiff base: Colorimetric and fluorogenic chemodosimeter for Hg2+ ions in an aqueous medium.

Simple pyrene-based chemosensors 1 to 3, were synthesized from pyrene-1-carboxaldehyde and they were characterized using various spectroscopic techniques like UV-Vis, FT-IR, Mass, 1H NMR and 13C NMR. Among synthesized receptors, the receptor 1 shows high selectivity towards Hg2+ ions. Further, the high selectivity of receptor 1 towards Hg2+ ions in the presence of various other interfering metal ions like Ni2+, Zn2+, Mn2+, Co2+, Cu2+, Cr3+, Fe3+, Al3+, Ag+, Fe2+, Cd2+, Mg2+, Pb2+, Ca2+, Na+, K+ was confirmed by UV-Vis and fluorescence methods. The detection limit for Hg2+ ions was found to be 0.270 μM. The chemodosimetric irreversible hydrolysis of the receptor 1 in the presence of Hg2+ was studied by UV/Vis, fluorescence, FT-IR, LC-MS, 1H NMR and theoretical DFT study. Further, the real life applications of receptor 1 for the determination of Hg2+ ions were demonstrated by UV-Vis method.