Synthesis and application of fluorescent probes for Cu2+and H2S detection based on Rhodol's "on-off-on" mechanism

Cu2+ 2 + and H2S 2 S have potential effects on environmental pollution and human health, so how to detect these substances with high selectivity and sensitivity has become an important research topic. In this study, we designed and synthesized a fluorescent probe based on Rhodol structure that can realize sequential detection of Cu2+ 2 + and H2S. 2 S. Due to the paramagnetic effect of Cu2+, 2 + , the strong fluorescence intensity is quenched after the addition of Cu2+. 2 + . When H2S 2 S was added to the solution (Probe C-Cu 2 + ), the fluorescence intensity was significantly enhanced and recovered. Therefore, the interaction process is accompanied by an "on-off-on" phenomenon of fluorescence intensity. Moreover, the probe has high sensitivity, low cytotoxicity and low detection limits, with detection limits of 6.6 nM and 10.4 nM for Cu2+ 2 + and H2S, 2 S, respectively. The mechanism of copper ion recognition by probe was revealed by high resolution mass spectrometry and theoretical study (DFT). The probe was also applied to identify Cu2+ 2 + and H2S 2 S in cells by fluorescence imaging sequence. This indicates that the probe has real application value in the sequential recognition of Cu2+ 2 + and H2S 2 S