A novel ratiometric and colorimetric fluorescent probe for hypochlorite based on cyanobiphenyl and its applications.

Reported here is a novel ratiometric and colorimetric fluorescent probe 1 for hypochlorite based on cyanobiphenyl and diaminomaleonitrile. This probe 1 was designed based on the mechanism that ClO selectively cleaved the hydrazone bond (-C=N-) in this probe and released the fluorophore, 3-formyl-4-hydroxy-4-biphenylcarbonitrile. The addition of ClO to the solution of probe 1 resulted in a very large blue-shift in both fluorescence (107 nm) spectra and an obvious fluorescence color change from red to green. Furthermore, this probe displays a rapid response (30 s) and a low detection limit (3.34 × 10 M, based on LOD = 3σ/slope) in detecting ClO. Importantly, practical utility of this probe for the selective detection of ClO in living cells has been successfully demonstrated, illustrating the great potential for biological analysis. Additionally, the probe 1 was also successfully applied to the detection of ClO in real water sample.