Magnetic solid-phase extraction based on Fe3O4@COF-TAPB-TPA for determining polycyclic aromatic hydrocarbons in foods and environmental water by HPLC.

A magnetic covalent organic framework (Fe3O4@COF-TAPB-TPA) was designed and synthesized via a mild approach for the magnetic solid-phase extraction (MSPE) of polycyclic aromatic hydrocarbons (PAHs) coupled with HPLC analysis. Density functional theory (DFT) calculations were performed to elucidate the adsorption mechanism, revealing that van der Waals forces and π–π stacking interactions are the primary driving forces, complemented by hydrogen bonding. Following optimization of key parameters (adsorbent dosage, eluent type, pH, ionic strength, and adsorption time), the developed method demonstrated excellent analytical performance, including wide linear ranges (R2 ≥ 0.991), low limits of detection (0.021–0.098 µg L− 1) and quantification (0.068–0.517 µg L− 1), and satisfactory recoveries (57.52%–119.34%). The practical applicability of the method was validated through successful analysis of PAHs in water, milk, honey, and green tea beverages, highlighting its potential for routine monitoring in complex food matrices.