Fabrication of magnetic porous organic framework for effective enrichment and assay of nitroimidazoles in chicken meat

A magnetic porous organic framework (M-POF) was rationally designed and served as a sorbent for magnetic solid-phase extraction of six nitroimidazoles from chicken meat prior to their assay by high-performance liquid chromatography with diode array detection. The M-POF exhibited good magnetic responsiveness and outstanding affinity to nitroimidazoles with large adsorption capacity up to 36 mg g −1 . Under optimal conditions, the developed method offered good linearity ( r  greater than 0.992) in the range of 1.5–100.0 ng g −1 , low limits of detection (S/N = 3) of 0.5–0.8 ng g −1 , low limits of quantification of 1.5–2.5 ng g −1 and high enrichment factors of 80–175 for the nitroimidazoles. The method was successfully applied to analyze nitroimidazoles in chicken meat. The recoveries were 80.2–118% with relative standard deviations lower than 12%. The adsorption mechanism was further explored and the results showed that the M-POF exhibited adsorption potential for compounds with strong polar interactions.