A novel colorimetric chemosensor based on 2-[(carbamothioylhydrazono) methyl]phenyl 4-methylbenzenesulfonate (CHMPMBS) for the detection of Cu(II) in aqueous medium

In this study, 2-[(carbamothioylhydrazono)methyl-phenyl-4-methylbenzenesulfonate (CHMPMBS), which exhibits selective colorimetric chemosensor properties for Cu(II) ions, was synthesized and characterized by NMR and FT-IR spectroscopy. The CHMPMBS chemosensor demonstrated high sensitivity and selectivity toward Cu(II) in an aqueous media in the presence of many other competing cations (Na(I), Mg(II), Al(III), K(I), Ca(II), Cr(III), Mn(II), Fe(III), Fe(II), Co(II), Ni(II), Cu(II), Zn(II), Sr(II), Ag(I), Cd(II), Ba(II), and Pb(II). By forming a complex of 1: 1 stoichiometry (Cu: CHMPMBS) with Cu(II), the developed chemosensor gave a distinctive color change from pale yellow to pale green. CHMPMBS exhibits a rapid and accurate colorimetric assay for naked-eye detection of Cu(II) ions with a detection limit of 8.12 mu M. Furthermore, the potential application of CHMPMBS has been extended to detect Cu(II) ions with functional recovery in both natural and simulated water samples. Furthermore, the Cu(II)-CHMPMBS complex was synthesized and characterized. The thermodynamic (& UDelta;G, & UDelta;H, and & UDelta;S) and kinetic (E-a) parameters were investigated at four temperatures. Further, the binding constant of CHMPMBS, which binds to Cu(II) ions according to 1:1 stoichiometry, was determined to be 2.47 x 10(4) M-1. Graphical Abstract