An experimental and theoretical study on mechanistic insights into urolithin-based ratiometric fluorescent probe for...

Fluoride detection has been playing an important role in chemical, biological, and medicinal field, especially for keeping physical health and resisting environmental pollution. Herein, a urolithin B fluorescent probe has been successfully developed with good sensitivity, selectivity, anti-interference ability. The low limit of detection (LOD) refers to 0.156 μM, and the instant response time to F^- is less than 1 s. The probe is suitable for quantitatively and qualitatively ratiometric detection for F^- in solution with two distinct emission bands at 425 (blue) and 566 nm (orange), with the coordinate change of CIE from (0.38, 0.41) to (0.22, 0.11). Urolithin B displayed a remarkable ratiometric fluorescence response towards F^-. The detection mechanistic was further proposed by NMR and electronic spectroscopic experiments combining with time-dependent density functional theoretical calculation.