Preparation of magnetic surface molecularly imprinted polymers for the selective extraction of triazines in environmental water samples

In this work, a magnetic molecularly imprinted polymer (Fe3O4@SiO2@MIPs) was prepared via a surface-imprinted method for the determination of the triazines in environmental water samples combined with high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). The Fourier transform infrared spectroscopy (FTIR) and vibrating sample magnetometer showed that the Fe3O4@SiO2@MIPs was successfully synthesised and exhibited superparamagnetism. The isotherm adsorption, selectivity and adsorption kinetics experiments showed that the Fe3O4@SiO2@MIPs exhibited excellent specific recognition and fast adsorption equilibrium for triazines. The adsorption process is spontaneous and endothermic. The isotherm adsorption was consistent with Scatchard model and adsorption kinetic fit pseudo-second-order kinetic model. Under the optimised adsorption conditions, the Fe3O4@SiO2@MIPs was directly used to selectively enrich six triazines in environmental water samples. The enrichment volume was up to 500mL, and the matrix effects were down to 0.7-12.4%. The built method has excellent linearities in the range of 0.25-500ngL(-1) with R-2 in the range of 0.998-0.999, lower limit of detections (0.02-0.08ngL(-1)) and higher precision (2.4-7.2%). The Fe3O4@SiO2@MIPs is expected to be widely applied to the direct enrichment of triazines in bulk environmental water samples.