β-Cyclodextrin-/AuNPs-functionalized covalent organic framework-based magnetic sorbent for solid phase extraction and...

β-Cyclodextrin-functionalized magnetic covalent organic framework (Fe₃O₄@COF@Au-β-CD) was developed as sorbent for magnetic solid phase extraction of trace sulfonamides in meat samples prior to HPLC-MS/MS analysis. The sorbent was synthesized by loading gold nanoparticles onto a Fe₃O₄@COF surface and then functionalized by thiolated-β-cyclodextrin immobilization via Au-S bonding formation. The prepared composite material was employed for sulfonamides extraction. The main parameters were optimized to obtain the best extraction efficiency. The experiments of adsorption kinetics were carried out to investigate the adsorption mechanism. Results showed the pseudo-second-order kinetic was better fitted with the adsorption kinetics of sulfonamides. Under optimized conditions, the magnetic solid phase extraction-HPLC method showed good linearity (R² ≥ 0.9936), and the limits of detection were in the range of 0.8-1.6 μg kg^-1. The proposed method was successfully used for quantitation of sulfonamides in real samples. The recoveries ranged from 78.9 to 112.0% with relative standard deviations (RSDs) < 10% (n = 5). The proposed method exhibited great potential for enrichment and determination of sulfonamides in many other food or environment samples. Graphical abstract.