Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University, Beijing 100048, China; School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China; Key Laboratory of Life-Organic Analysis of Shandong Province, Qufu Normal University, Qufu 273165, China. Electronic address: [Email]
The present research reported a facile strategy for the synthesis of a novel magnetic covalent organic frameworks (Fe3O4@COF(TpDA)) material and applied it as a sorbent for magnetic solid phase extraction of plant growth regulators from fruits and vegetables. The prepared Fe3O4@COF materials showed many attractive features involving large specific surface area (180.2 m2/g) and high saturation magnetization (62.3 emu/g), which enabled it an ideal sorbent for sample pretreatment. The experimental conditions affecting the extraction performance were optimized systematically, including eluent, amount of sorbent, adsorption time and desorption time. The extracted samples were detected by HPLC-DAD. Under the optimized conditions, the proposed method exhibited good linearity (R ≥ 0.9990) and low limits of detection (4.68-7.51 μg/L). Satisfactory recoveries were calculated to be 83.0-105.0%. Finally, the proposed method was successfully applied to determination of plant growth regulators in fruits and vegetables, indicating the potential prospect of the Fe3O4@COF(TpDA) materials in sample pretreatment.