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

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 Hg²⁺ 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 Hg²⁺, 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.