simultaneous determination of ractopamine, chloramphenicol, and zeranols in animal-originated foods by lc-ms/ms analysis with immunoaffinity clean-up column

A novel analytical method employing immunoaffinity column (iac) clean-up coupled with liquid chromatography-tandem mass spectrometry (lc-ms/ms) method was developed for simultaneous determination of ractopamine, chloramphenicol, and zeranols (α-zearalanol, β-zearalanol, zearalanone, α-zearalenol, β-zearalenol, and zearalenone) in animal-originated foods. the sample was first digested by β-glucuronidase/sulfatase and then extracted with ethyl acetate-diethyl ether (9:1, v/v). the extracted solution was evaporated to dryness and then the residue was dissolved by 2 ml of 50% acetonitrile solution. after filtration, 1 ml filtrate was diluted to 10 ml with pbs. the reconstituted solution was cleaned up with immunoaffinity column and then analyzed by high performance liquid chromatography-tandem mass spectrometry (lc-ms/ms). the established method was shown to be sensitive efficient and reliable as indicated by the linearity (r 2 ≥ 0.9994), precision (rsd ≤ 1.7%), average recovery (72.3–103.2%), and the limit of detection (0.05–0.10 μg/kg). the method can be used for determination of trace residues of ractopamine, chloramphenicol, and zeranols in animal-originated foods.