Fabrication of a functionalized magnetic covalent organic framework composite as an efficient adsorbent for sulfonamide extraction from food samples

A carboxyl group functionalized magnetic covalent organic framework nanocomposite was prepared as a magnetic solid-phase extraction adsorbent for extraction of seven sulfonamides from meat samples. The obtained magnetic covalent organic framework composites were characterized in terms of morphology and magnetism. Due to the presence of aromatic benzene rings and amino groups in the structures of sulfonamides, π–π interactions and electrostatic interactions are the main mechanisms for adsorbing sulfonamides by adsorbents. The extraction parameters including adsorbent dosage, pH, adsorption time, ionic strength, eluting solvent, and desorption time were systematically investigated. Under the optimized extraction conditions, an efficient and convenient method for the extraction and determination of sulfonamides from meat samples was developed by combining magnetic solid-phase extraction and HPLC-MS/MS. The proposed method provided a good linearity with coefficients of determination (R2) ≥ 0.9984, low LODs (0.1–0.4 μg kg−1) and the spiked recoveries into meat samples were obtained in the range of 85.34–102.61%. The nanocomposite is a promising adsorbent for the efficient extraction of sulfonamides from complex food samples.