Abstract: A magnetic molecularly imprinted polymer (MMIP) was prepared by surface imprinting technology using Fe3O4@SiO2 grafted with the silane coupling agent methacryloxy propyl trimethoxyl silane (KH570) as the magnetic carrier and bitertanol as the template molecule. MMIP prepared under optimized conditions was characterized by infrared spectoscopy, transmission electron microscopy and magnetic measurement. The adsorption properties of the MMIP for bitertanol were evaluated by static adsorption experiments. The MMIP was used as the solid phase extraction (SPE) adsorbent to extract bitertanol from various food samples such as millet and wheat, which was then purified before being detected by high performance liquid chromatography (HPLC). The results indicated that the MMIP, with a core-shell structure, could recognize bitertanol and its structural analogues. The proposed method showed good linearity with correlation coefficient ≥ 0.999 6. The limit of detection was 0.01–0.02 μg/mL, and the average recoveries were between 87.7% and 104.3%, with relative standard deviations from 1.39% to 3.46% (n = 5). The MMIP was suitable for the rapid separation and purification of triazole pesticides from foods, and the developed analytical method could selectively and fast detect triazole pesticide residues in foods.

Key words: bitertanol; magnetic molecular imprinting; molecularly imprinted polymer; solid phase extraction; rapid analysis