Molecularly imprinted polymer coated Eu-BCA MOF for highly selective detection of Zearalenone in corn oil.

Based on the strategy of rare-earth MOF coated with molecular imprinted polymer (MIP), a high-performance fluorescent colorimetric sensor was constructed for the detection of Zearalenone (Zen). Bisquinoline acid was selected as the organic ligand to construct the Eu-BCA MOF with europium nitrate, then the quinoline-N in the ligand of MOFs was used to participate in the construction of the SiO2 molecularly imprinted layer to form the Eu-BCA@SiO2-MIP, which can respond quickly to trace Zen in the range of 0-1.56 × 10-6 mol L-1, and the detection limit is as low as 1.66 ng mL-1. The long fluorescence lifetime of Eu enables time-resolved fluorescence detection, which helps to eliminate the interference of various non-specific fluorescence and short-lifetime fluorescence, thereby improving the detection sensitivity and interference immunity. The recovery rate of Zen in corn oil reached 96.88 %-107.40 %. The sensing mechanism was studied by the calculation of Density Functional Theory (DFT) and fluorescence and infrared spectroscopy. Eu-BCA@SiO2-MIP is a sensitive and efficient Zen detection material with superior selectivity, which is of great significance for food safety and grain storage.