A small molecule modified UiO series MOFs for simultaneous detection of Fe and Zn.

Iron and zinc are two metal ions with important roles in biology, industry and the environment, however, the excess or deficiency of both Fe and Zn can have negative effects on organisms and environment. Therefore, the development of efficient method for simultaneous detection of Fe and Zn provides timely information on metal content, simplifies operations and improves efficiency. In this work, a small molecule (COOH-BPEA) of recognizing Zn modified the four metal-organic-framework (MOF) (UiO-66-X(66, OH, NH and OH/NH)) was developed for the simultaneous detection of Fe and Zn. The fluorescence signal of the small molecule is enhanced by small molecule chelating Zn to block the photoinduced electron transfer (PET) effect. The fluorescence signals of the UiO series MOFs were quenched through Fe with electron transfer and static quenching effect (SQE). It's worth mentioning that the emission wavelengths of the small molecules and MOFs did not interfere with each other. The UiO-66-NH@BPEA with optimal performance was selected by fluorescence spectra for the detection of Fe and Zn with detection limit of 0.175 μM and 0.021 μM, respectively. The nanoprobe provides a fast response (less than 1 min) for both Fe and Zn. Finally, we applied it to the simultaneous detection of Fe and Zn in environmental water, human serum and cell lysates.