Selective fluorescent detection of Zn²⁺ by a rhodanine‐based chemosensor

Abstract

A rhodanine-based fluorescent chemosensor DHM, 3-[(E)-{[4-(diethylamino)-2-hydroxyphenyl]methylidene}amino]-2-sulfanylidene-1,3-thiazolidin-4-one, has been designed and synthesized. Sensor DHM showed unique optical properties with large fluorescence change on detecting Zn 2+ . Most cations did not disturb the binding of DHM with Zn 2+ , while Co 2+ and Cu 2+ displayed fluorescence quenching and Fe 2+ , Fe 3+ , and Ni 2+ did some interference. With outcomes of Job plot and electrospray ionization (ESI)-mass data, the binding ratio of DHM to Zn 2+ was determined as a 1:1. Moreover, DHM could detect Zn 2+ with a low detection limit (1.33 μM). DHM could efficiently analyze Zn 2+ in a real environment with positive recovery and relative standard deviation (RSD) and be recyclable reliably with ethylenediaminetetraacetic acid (EDTA). DHM-doped test kits can be readily used for recognizing Zn 2+ . The binding feature of DHM to Zn 2+ was illustrated by ESI-mass, nuclear magnetic resonance (NMR) titration, and calculations.

Phenylethylamine Derivative of Calix[4]arene Schiff Base for Fluorometric Detection of Zinc Ion

“…Therefore, many heavy metals such as Zn2+ ion need to be detected in a sensitive and selective way. In recent years, many different molecules have been studied in the literature for the optical detection of Zn 2+ ion by using benzothiazole [12,13], antracene [14], benzidine [15], triphenylamine [16,17], cyanobiphenyl [18], benzotriazole [19], tetrahydroquinazole [20], dinitrophenyl [21], thiophene [22], rhodanine [23], benzoimidazole [24], phenanthroline [25], naphthalene [26], 1,10-phenanthroline [27], BINOL [28] and sulphonamide [29]. Among these molecules, calixarenes play an important role.…”