Triazole pesticide residues analysis based on functionalized magnetic materials and solid phase microextraction collaborative technology in tea drinks

An integrated collaborative extraction technology of solid phase microextraction (SPME) enrichment and functional magnetic material cleanup was constructed and applied to the analysis of triazole pesticide residues in tea drink samples. The magnetite (Fe₃O₄) nanoparticles modified with 3-(N,N-diethylamino) propyltrimethoxysilane (Fe₃O₄-PSA) was selected as the cleanup adsorbents to remove the matrix interferences. The target analytes were microextracted by SPME needle and analyzed by GC-MS. In this method, SPME conditions such as extraction time, extraction temperature, salinity and pH value were optimized. Meanwhile, the amount of magnetic material and SPME conditions were optimized by orthogonal experiments. Under the optimal conditions, the 19 triazole pesticides showed good linearity in the concentration range of 0.002-0.2 mg/L, and the correlation coefficient (r) was greater than 0.99. The limits of detection (LOD) ranged from 0.00012 to 0.0089 mg/L and LOQ was 0.002 mg/L. Using the matrix matched calibration curves, the recoveries ranged from 71% to 98% with relative standard deviation (RSD) lower than 16% at three spiked concentrations. Compared with the conventional method, this method was simple, convenient, reliable and environment-friendly. It is suitable for the analysis of triazole pesticide residues in tea drinks.