Novel fluorescent probe based on benzotriazole selective detection Hg²⁺ in real samples

Abstract A novel reaction probe O‐(2‐(4‐(1H‐benzo[d][1,2,3]triazol‐1‐yl)phenyl)‐4‐oxo‐4H‐chromen‐3‐yl) O‐phenyl carbonothioate ( O‐PCBE ) synthesized from benzotriazole and benzopyrone. The structure was confirmed by NMR, HRMS, and IR characterization. The probe O‐PCBE was non‐fluorescent until Hg 2+ was added, which markedly enhanced fluorescence with an excitation wavelength of 536 nm. The detection mechanism has been thoroughly validated through DFT calculations. Probe O‐PCBE can sensitively detect Hg 2+ , achieving a detection limit of 1.08 × 10 −7 mol/L. Within a pH range of 4–10, the probe exhibits high selectivity, a rapid detection response (2 min), and excellent anti‐interference properties. Additionally, the probe demonstrates good recovery and accuracy in detecting real water samples.