Separation of β-agonists in pork on a weak cation exchange column by HPLC with fluorescence detection

Abstract

The separation of β-agonists was performed for the first time on a silica-based weak cation exchange (WCX) stationary phase in which aqueous electrolyte solution with small amount of organic solvent was used as the mobile phase. Compared to the organic solvent used in reverse phase HPLC mode, the merits of using an aqueous mobile phase include unique selectivity, environment-friendly operation and reduced operation costs. The effective separation of four commonly used β-agonists including salbutamol, terbutaline, metoprolol and ractopamine, were achieved with the mobile phase of 20 mM ammonium formate/acetonitrile (5%). The interference from the hydrophobic analytes could be easily eliminated due to their poor retention under this mode. The detection limits for the above analytes when fluorescence detection is employed were in the range of 3.55–8.32 μg kg⁻¹ and the spiked recoveries for metoprolol for the spike sample reached about 83% and the relative standard deviation (RSD) was 4.7%.