A Novel Ethylenediamine Bridged Indole-BODIPY Schiff Base Applied for Selective Response to Fe, Cu and Al Detection

In this work, fluorescent compounds with Schiff base functional groups were obtained by using ethylenediamine bridged indole-BODIPY. The fluorescent probe Indole-ethylenediamine-BODIPY (ID-E-BP) and its performance in recognizing metal ions were investigated by UV and fluorescence spectroscopy, which showed that the fluorescent probe had a maximum absorption wavelength of 536 nm and a maximum emission wavelength of 557 nm. The fluorescent probe exhibited a fast and sensitive fluorescence quenching response effect in ethanol solution for Fe³⁺, Cu²⁺ and Al³⁺, and the detection limits were 0.24 µM, 0.19 µM and 0.15 µM, respectively. The ID-E-BP sensor is basically not affected by metal ions and environmental pH, and can be successfully applied to test strips and real water samples to detect metal ions. In addition, density functional theory (DFT) was calculated, and the results showed that the fluorescence probe combined with Fe³⁺, Cu²⁺ and Al³⁺ had a stable configuration. In summary, the sensor synthesized in this paper can be stably combined with metal ions and used to identify special metal ions.