A Schiff Base-Functionalized Triphenylamine Fluorescent Probe for Selective and Sensitive Detection of Cu2+ in Aqueous Media

Heavy metal Cu 2+ from industrial discharge continuously accumulates in ecosystems, posing threats to human health and ecological balance. Researchers successfully synthesized a novel fluorescent probe, TPA-OPD , via a Schiff base reaction between triphenylamine and o-phenylenediamine. TPA-OPD exhibits rapid, highly selective, and sensitive fluorescence quenching in response to Cu 2+ , along with excellent anti-interference capability. The binding mechanism between Cu²⁺ and TPA-OPD was confirmed by Job’s plot, Fourier-transform infrared spectroscopy, mass spectrometry, nuclear magnetic resonance, and Gaussian calculations. TPA-OPD effectively detects Cu 2+ in real-world environmental samples such as tap water and river water, demonstrating strong potential for monitoring Cu 2+ pollution. Graphical None = 95% H2O, 1 = Cu²⁺, 2 = Na⁺, 3 = K⁺, 4 = Cs⁺, 5 = Mg²⁺, 6 = Al³⁺, 7 = Ca2+, 8 = Ba²⁺, 9 = Cd²⁺, 10 = N₂H₆²⁺, 11 = Sr²⁺, 12 = NH₄⁺, 13 = Co2+, 14 = Zn2+, 15 = Ag+, 16 = Ni²⁺, 17 = SO₄²⁻, 18 = CO32-, 19 = Cl- , 20 = NO₃⁻, 21 = CH₃COO⁻