A Quinoline-Based Fluorescent Labelling for Zinc Detection and DFT Calculations

8-carboxamidoquinoline derivatives were gradually investigated as zinc's label in resolving weak water solubility, poor membrane permeability, and difficulty measuring free Zn2+ ion cells quantitatively. The potential of 2-oxo-2-(quinolin-8-ylamino)acid (OQAA) was prepared characterized spectroscopically. Theoretical experimental data OQAA compared discussed. optimized molecular structure, orbital HOMO-LUMO, energy band gaps, electrostatic (MEP) carried out using the DFT method with Becke-3-Parameter-Lee-Yang-Parr (B3LYP) 6-31G(d,p) basis set. intermolecular interaction OQAA-Zn is calculated by hybrid GEN a set LANL2DZ for DFT/6-31G(d,p) ligand. exhibited remarkable excellent fluorescence enhancement selective qualitatively only than other metal cations tested (Fe2+, Cu2+, Co2+, Ni2+, Hg2+, Cd2+) under long wavelength. Job's plot 1H NMR titrations indicate OQAA-Zn2+ has binding ratio at 1:1 stoichiometry (M1L1). Substantial shifting amide N-H proton to higher chemical shift intensity peak decrease abruptly implies that an amide. These changes confirmed interactions among ligand ion. As result benefits discussed, could effectively selectively optimize fabricate sensors.