Synthesis and Application of Salicylhydrazone Probes with High Selectivity for Rapid Detection of Cu²

Using the aldehyde amine condensation procedure and the triphenylamine group as the skeleton structure, the new triphenylamine-aromatic aldehyde-succinylhydrazone probe molecule DHBYMH was created. A newly created acylhydrazone probe was structurally characterized by mass spectrometry (MS), NMR, and infrared spectroscopy (FTIR). Fluorescence and UV spectroscopy were used to examine DHBYMH's sensing capabilities for metal ions. Notably, DHBYMH achieved a detection limit of 1.62 × 10^-7 M by demonstrating exceptional selectivity and sensitivity towards Cu²⁺ ions in an optimum sample solvent system (DMSO/H₂O, (v/v = 7/3); pH = 7.0; cysteine (Cys) concentration: 1 × 10^-4 M). NMR titration, high-resolution mass spectrometry analysis, and DFT computation were used to clarify the response mechanism. Ultimately, predicated on DHBYMH's reversible identification of Cu²⁺ ions in the presence of EDTA, a molecular logic gate was successfully designed.