Luminescent metal organic frameworks with recognition sites for detection of hypochlorite through energy transfer

A luminescent metal organic framework (LMOF) of type UiO-66-NH2 was chosen for specific and sensitive detection of trace levels of hypochlorite. Hypochlorite causes the quenching of the blue fluorescence of nano-UiO-66-NH2 (with excitation/emission maxima at 325/430 nm), and this finding forms the basis for a fluorometric assay for hypochlorite. The method overcomes disadvantages of conventional redox-probes which are interfered by oxidants with oxidation capability stronger than that of hypochlorite. Compared with other fluorescent probes for sensing hypochlorite, UiO-66-NH2 has a comparable detection limit of 0.3 μmol L−1 and a broad linearity relationship in the range of 1–8 μmol L−1. The probe was successfully applied to the detection of hypochlorite in complex water samples and living Hela cells.