Simultaneous Determination of Cimaterol, Salbutamol, Terbutaline and Ractopamine in Feed by SPE Coupled to UPLC

An ultra performance liquid chromatography (UPLC) method was established for the simultaneous determination of cimaterol, salbutamol, terbutaline, and ractopamine in feed. Target compounds were extracted with methanol and centrifuged. The supernatant was then transferred and concentrated, and applied to a solid phase extraction MCX cartridge for clean-up before UPLC analysis. The calibration curves for the four beta-agonists were good linear in concentration range of 0.05-1.0 mu g mL(-1) with the correlation coefficients (r) over 0.999. The average recoveries were in the range of 90.1-101.4% with relative standard deviation values lower than 8.0%.