Synthesis and Computational Study of an Optical Fluorescent Sensor for Selective Detection of Ni<sup>2+</sup> Ions
Maria Sadia, Jehangir Khan, Rizwan Khan, Syed Wadood Ali Shah, Adil Zada, Muhammad Zahoor, Riaz Ullah, Essam A. Ali
Abstract
High Resolution Image Download MS PowerPoint Slide The presence of an abnormal amount of Ni 2+ in the human body causes various health issues. Therefore, this work aimed to synthesize the curcumin-based fluorescence-on sensor P [2,6-bis(( E )-4-chlorobenzylidene)-cyclohexan-1-one] that was capable of selectively responding to Ni 2+ ions in aqueous solution. The structure of P was confirmed by 1 H NMR and Fourier transform infrared (FTIR) spectroscopy. The Ni 2+ ion sensing was based on the fluorescence enhancement of the fluorophore ( P ) in neutral aqueous medium. The response of the P -based sensor was highly selective toward Ni 2+ ions, whereas the possible interferences from other metal cations were negligible. P had a fast response; it was selective and had a sensitive detection limit (LOD = 2 × 10 –10 M) toward Ni 2+ ions in neutral medium with a high association constant ( K ) value of 3.6 × 10 5 M –2 for the complex formation between the P and Ni 2+ ions. Job’s plot and DFT calculations proved that the binding stoichiometry of P for Ni 2+ was 2:1. P was recovered using EDTA as a chelating agent after being employed as a fluorescent sensor. These characteristics ensured the potential use of P as a new class of chemosensor for environmental applications.