MIP-coated Eu(BTC) for fluorometric determination of Lincomycin in eggs
Lincomycin (LCM) with low ultraviolet (UV) absorption requires complex instrumental for determination. Here, a novel fluorometric probe based on Europium metal organic framework coated by molecularly imprinted polymers (Eu(BTC)-MIP) was fabricated for the selective determination of LCM. First, highly luminescent Eu(BTC) was synthesized at room temperature. Then, through a simple co-polymerization process, MIPs were formed on the Eu(BTC) surface in the presence of LCM as template molecules to obtain Eu(BTC)-MIP. Eu(BTC) acted as supporting substrates and antennas, and the MIPs layer provided specific binding sites for LCM. Taking the advantages of both Eu(BTC) and MIPs, the probe had a long emission lifetime, strong fluorescence and specific recognition. Under optimized conditions, the probe achieved the selective determination of LCM from 10 to 100 μg/L with a detection limit (LOD) of 7.18 μg/L (S/N=3). This method is more attractive because of its low cost, good selectivity, ready availability and simple manipulation without complex instrumental for determination. Furthermore, the probe was successfully employed to detect LCM in eggs samples with a recovery from 88.02% to 97.29% and a relative standard deviation (RSD) less than 3.46%. The satisfactory results demonstrated that the proposed probe based on Eu(BTC)-MIP could be used for quantitative analysis of LCM and provided great potential for LCM determination in food samples. Also this study provides a new perspective for the determination of weak ultraviolet absorption or non fluorescent substances without conjugated groups.