Detection of copper in tea and water sample: A click-oriented azomethine-based 1,2,3-triazole fluorescent chemosensor with reversible INHIBIT logic gate behavior and computational aspects

Abstract

A fluorescent azomethine-scaffolded-1,2,3-triazole linked chemosensor was synthesized utilizing alkyne and azidomethylbenzene via Cu(I)-catalyzed click chemistry. The compounds (3–5 and L6) were analyzed using FTIR, 1H NMR, 13C NMR, and GCMS–. The exploration of ion sensing ability of L6 complex, using UV–Vis and fluorescence spectroscopy in ACN:H2O (4:1) medium resulted in detection of Cu(II) ions, exclusively. Further L6-Cu(II) complex was characterized via FTIR, FE-SEM, LCMS and supported by DFT studies. A significant structural modification has rendered the current probe as highly selective for Cu2+ ions, with ‘Turn-On’ response. The chemical receptor (L6) establishes 1:1 molar ratio with Cu(II) ions with binding constant of 6.0 × 104 M−1 and excellent detection limit of 20 nM. In addition, the sensitive reversible behavior of probe (L6) with two chemical inputs (Cu2+ and EDTA) contributes to the construction of an INHIBIT logic circuit. The Copper ion detection was effectively monitored for real-world samples like Black Tea with precise quantification of Copper(II) ions.