Room temperature fabrication of magnetic covalent organic frameworks for analyzing sulfonamide residues in animal‐derived foods
Zhen Gong, Qianqian Wan, Jiayi Song, Meng Li, Wenting He, Zixin Zhou, Ping Su, Chun‐Ting Zhang, Yi Yang
Abstract
Abstract A magnetic solid phase extraction method based on magnetic covalent organic frameworks (TpBD@Fe 3 O 4 ; 2,4,6‐triformylphloroglucinol (Tp) and benzidine (BD)) combined with high performance liquid chromatography has been developed to detect the sulfonamides including sulfadiazine, sulfamerazine, sulfamethazine, and sulfamethoxazole in milk and meat. TpBD@Fe 3 O 4 were synthesized at room temperature under mild reaction conditions with a simple and rapid operation. The TpBD@Fe 3 O 4 exhibited higher extraction efficiency because of the π–π and electrostatic interactions between the benzene ring structure of the TpBD and the sulfonamide molecules. The extraction conditions including the dosage of adsorbents, the type and dosage of eluent, the elution time, and the pH of the sample solution were fully optimized. The detection results showed good linearity over a wide range (50–5 × 10 4 ng/mL) and low detection limits (3.39–5.77 ng/mL) for the sulfonamide targets. The practicability of this magnetic solidphase extraction‐high‐performance liquid chromatography method was further evaluated by analyzing milk and meat samples, with recoveries of the targets of 71.6–110.8% in milk and 71.9–109.7% in pork. The successful detection of sulfonamides residues has demonstrated the TpBD@Fe 3 O 4 excellent practical potential for analyzing pharmaceutical residues in animal‐derived foods.