Determination of Nine β_2-Agonist Hormones Residues in Pork by GPC-SPE-RRLC-MS/MS

A gel permeation chromatography-solid phase extraction-rapid resolution liquid chromatography-tandem mass spectrometry(GPC-SPE-RRLC-MS/MS) method for the determination of 9 β2-agonist hormones including salbutamol,terbutaline,cimeterol,fenoterol,clenbuterol,ractopamine,clorprenaline,tulobuterol and penbutolol in pork has been developed.Pork samples were hydrolyzed with β-glucuronidase/arylsulfatase,extracted with tert-butyl methyl ether under ultrasonic incubation and cleaned up using gel permeation chromatography followed by solid phase extraction on an HLB column.After RRLC gradient elution separation on an Agilent Plus C18 column using methanol-water containing 0.1% formic acid as a mobile phase,the pooled eluate was qualitatively and quantitatively determined by tandem mass spectrometry under multi-reaction monitoring(MRM) mode.The limits of detection of this method were 0.1–0.3 μg/kg,and the developed calibration curves revealed excellent linearity with correlation coefficients larger than 0.996.At spiked levels of 0.3,2.0 μg/kg and 5.0 μg/kg,average recovery rates of 9 β2-agonist hormones were in the range of 79.35%–109.80%,with RSDs between 2.12% and 9.11%.This method was sensitive,reproducible,accurate and applicable for the determination of β2-agonist hormones in pork.