The design and synthesis of two imidazole fluorescent probes for the special recognition of HClO/NaHSO3 and their applications.

Two fluorescent probes (L1 and L2) based on an imidazole unit were synthesized for the specific detection of ClO- and HSO3-. Density functional theory (DFT) calculations were used to assist in designing the probes. As predicted, L1 could be used to detect ClO- in real water samples and in living cells. It was shown to be a quenching probe. L2 could be used to monitor HSO3- in living cells and is an enhanced fluorescence probe. Further details of the fluorescence recognition mechanism were obtained via HRMS analysis. Moreover, both fluorescent probes showed relatively low detection limits (0.96 and 0.59 µM, respectively), and fast and highly selective fluorescence responses.