A novel turn-on fluorescent probe based on berberine for detecting Hg2+ and ClO− with the different fluorescence signals

Development of a high performance fluorescent sensor from natural berberine for selective detection of metal ions and anions is a great challenge. Herein, a novel turn-on fluorescent probe TB for the detection of both Hg2+ and ClO− has been successfully designed and synthesized from berberine. The probe TB showed good selectivity and sensitivity to Hg2+ and ClO− in CH3OH/PBS (7:3, v/v, pH = 7.4, 10 mM) solution, and it emitted yellow fluorescence upon the addition of Hg2+ and cyan fluorescence upon the addition of ClO−. Moreover, the limits of detection (LOD) for Hg2+ and ClO− were calculated to be 0.409 μM and 0.295 μM based on 3σ/k method, respectively. In addition, the mechanisms of TB for sensing Hg2+ and ClO− were established based on HRMS, Job's plot and 1H NMR titrations. Furthermore, the probe TB displayed many important practical applications, such as water sample analysis, imaging in plant cell and zebrafish bioimaging.