A highly selective and sensitive turn on optical probe as a promising molecular platform for rapid detection of Zn (II) ion in acetonitrile medium: Experimental and theoretical investigations

摘要

A highly Zn2+ ion responsive novel cation sensor (L) based on the dual mechanism (ESIPT/ICT) was designed, synthesized and characterized. The sensor L shows great turn on selectivity for Zn2+ ion in 1:1 stoichiometric manner via rapid color change and 5-fold fluorescence enhancement in CH3CN over other interfering cations. The addition of Zn2+ ion to L, triggers the deprotonation of imidolic and hydroxylic protons of L, which in turn shows an enhanced red shift in both UV-Vis and fluorescence spectra of the sensor. The limit of detection and binding constant obtained are well within those reported for Zn2+ ion. The theoretical calculations were correlated with experimental results to understand the sensing mechanism between host guest interactions and L distinguishes Zn2+ from Cd2+. Furthermore, bioimaging studies were undertaken to investigate practical usefulness of L to recognize Zn2+ ion using HeLa cells. (C) 2019 Elsevier B.V. All rights reserved.