Facile synthesis of magnetic zinc metal‐organic framework for extraction of nitrogen‐containing heterocyclic fungicides from lettuce vegetable samples

Abstract We present a simple method for the fabrication of a magnetic amino‐functionalized zinc metal‐organic framework based on a magnetic graphene oxide composite. The resultant framework exhibited a porous 3D structure, high surface area and good adsorption properties for nitrogen‐containing heterocyclic fungicides. The adsorption process and capacity indicated that the primary adsorption mechanism might be hydrogen bonding and π‐π conjugation. In addition, an optimized protocol for magnetic solid phase extraction was developed (such as adsorbent content, pH, and desorption solvent), and utilized for the extraction of nitrogen‐containing heterocyclic fungicides from vegetable samples. Quantitation by high performance liquid chromatography coupled with tandem mass spectrometry offered a detection limit of 0.21–1.0 μg/L (S/N = 3) with correlation coefficients larger than 0.9975. These results demonstrate that magnetic amino‐functionalized zinc metal‐organic framewor is a promising adsorbent for the extraction and quantitation of nitrogen‐containing heterocyclic fungicides.