Preparation of magnetic MOFs for use as a solid-phase extraction absorbent for rapid adsorption of triazole pesticide residues in fruits juices and vegetables.

Detection of low levels of triazole fungicides in agricultural product matrices is important. Although several detection methods have been developed, all have some drawbacks, such as being time-consuming, requiring complex sample pretreatment, and consuming large volumes of organic solvents. There is an urgent need for a simple and rapid detection method for triazole fungicides. In this study, the adsorbent composite material magnetic MOFs based on Fe3O4-MWCNT was synthesized by in-situ polymerization at room temperature, and was applied to extract triazole pesticides from fruits and vegetables. High-performance liquid chromatography-tandem mass spectrometry was used for quantification. Under optimized conditions, the constructed detection method showed a low detection (LOD) of 0.52-1.83 µg/L (S/N = 3) and wide linear range of 5.00-500.00 µg/L for triazole fungicides in the fruit and vegetable samples. The method recovery for spiked fungicides (10, 50, and 100 µg/L) in cabbage, spinach, orange juice, and apple juice ranged from 62.80% to 94.20%. The constructed detection method has a lower detection limit than previously reported methods and has a higher sensitivity for triazole pesticide residues in complex matrices.