Click modified bis-appended Schiff base 1,2,3-triazole chemosensor for detection of Pb(II)ion and computational studies

A novel 1,2,3-triazole linked schiff base chemosensor was stitched via Cu(I) catalyzed click reaction with excellent yield, high selectivity, sensitivity and characterized using fourier transform infrared spectroscopy (FTIR), NMR (1H and 13C), mass spectrometry (MS), CHN analysis, thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). The developed chemosensor was investigated for it's optical properties using UV-visible and fluorescent spectroscopy. The detected limit of the synthesized probe was estimated 0.25 mu M from fluorescence spectroscopy, which is particularly below the WHO guidelines. The binding stoichiometric (2:1) of ligand was confirmed by the job's plot and the binding constant was determined to be 4.1 x 106 M-1 and 1.4 x 105 M-1 from the B-H plot and the Stern-Volmer curve, respectively. These results establish the developed chemosensor as a potent probe for analytical and practical applications. The optimized geometrical structure of the probe (4) was run on Gaussian 09 program using DFT method with (B3LYP)/6-311G++(d,p) basis set of hybrid density functional theory.