Highly Selective and Sensitive Colorimetric and Fluorescent Chemosensor for Rapid Detection of Ag+, Cu2+ and Hg2+ Based on a Simple Schiff Base

A new reversible colorimetric and fluorescent chemosensor MMIP based on a simple Schiff base has been successfully synthesized. MMIP exhibited high selectivity and sensitivity towards Ag+, Cu2+ and Hg2+ ions with a short response time in DMSO/H2O (1/1, v/v) solution among various metal ions, and the results could be monitored directly by naked eyes. The binding stoichiometry between MMIP and Ag+/Hg2+/Cu2+ has been determined to be 1:2 by Job’s plot and FT-IR analysis. MMIP could effectively detect Ag+, Cu2+ and Hg2+ over a wide pH range of 3–10. The good linear correlations were obtained in the concentration ranges of 0–20 μM for Ag+, Cu2+ and Hg2+. Thus sensor MMIP could be potentially used for the quantification of Ag+, Cu2+ and Hg2+ in aqueous solution.