Development and application of a new deep eutectic solvent based magnetic metal–organic framework adsorbent for the detection of fluorotelomer alcohols in edible oils

The enrichment of per- and polyfluoroalkyl substances (PFASs) poses significant challenges for environmental and food safety monitoring, given their toxic and persistent nature, highly fluorinated character, and low concentration. This study focuses on the construction of a new deep eutectic solvent (DES)-functionalized magnetic metal–organic framework (MOF) adsorbent for fluorotelomer alcohols (FTOHs) analysis in foods. The DES, composed of levulinic acid and trifluoromethoxylbenzene, was modified onto the surface of magnetic UiO-66-NH2 to enable the specific adsorption of FTOHs during the pretreatment process, which was then followed by GC–MS analysis. The method exhibited a limit of detection (LOD) ranging from 31.51 to 185.76 pg g – 1 with satisfactory recoveries (73.83 %-128.55 %), and was successfully used in detecting FTOHs in 12 edible oils samples with the concentrations ranging from 401.89 to 8006.18 pg g − 1. The proposed adsorbent exhibited significantly improved enrichment performance for PFASs, primarily attributed to the cooperative enhancement of double hydrogen-bonding interactions and fluorine affinity via the elucidation of 1H nuclear magnetic resonance (1H NMR), 19F NMR, and quantum chemical calculations. This study provided new insights and directions for the design and fabrication of selective materials to pretreatment ultra-trace emerging contaminants in complex matrices.