Magnetic covalent organic frameworks confined by ionic liquids for efficient enrichment of polycyclic aromatic hydrocarbons in edible oils

Increasing polycyclic aromatic hydrocarbons (PAHs) pollution in dietary is becoming a significant worldwide problem due to their direct threat to human health. To achieve rapid and sensitive detection of PAHs, nanocomposites were fabricated by confining ionic liquids (ILs) within magnetic covalent organic frameworks (MCOFs). After the confinement of [C 8 MIM][PF 6 ] into MCOFs, the resulting MCOF@8   C maintained high crystallinity comparable to that of the pristine MCOF, limited the diffusion of ILs and reduced the aggregation effect caused by their high viscosity. The MCOF@8   C/HPLC-FLD method gave low detection limits (0.01-0.15   µg   kg -1 ), good recoveries (85.32-99.57%) with RSDs ≤ 5.03% for seven PAHs congeners across five types of edible oils. In general, this study not only provides an excellent substitute for conventional multifunctional composites, but also develops a superior methodology for monitoring trace-level PAHs in complicated food matrices.