Fabrication of magnetic zeolitic imidazolate framework-7 supported graphene oxide for the extraction of fungicides from environmental water and soil samples

In this study, we report a facile method to prepare magnetic zeolitic imidazolate framework-7@graphene oxide (mag-ZIF-7@GO) composites with the assistance of polydopamine. Moreover, their potential for extracting fungicides from environmental water and soil samples is evaluated. Combining ZIF units and GO layers synergistically enhances the preconcentration of fungicides. A sensitive magnetic solid-phase extraction method based on mag-ZIF-7@GO coupled to LC-MS is developed to determine seven fungicides (pyrimethanil, triadimenol, flutriafol, tebuconazole, hexaconazole, diniconazole and bitertanol) as a function of optimised salt concentration, pH, extraction time, and desorption time. Under optimal conditions, the method exhibits good linearity, repeatability, and reproducibility. The limits of detection and limits of quantification for the seven fungicides are 0.58–2.38 ng/L and 1.95–7.94 ng/L, respectively. Furthermore, the proposed method is applied to determine trace fungicides in environmental water and soil samples, with recoveries of 81.8–96.7%, 87.2–96.3%, and 82.4–93.4% for pond water, river water, and soil, respectively. Therefore, this method has great potential for trace analysis of pollutants in complex environmental matrices.