| A QuEChERS sample pretreatment coupled with ultra high performance liquid chromatography-LTQ Orbitrap mass spectrometric（UHPLC-LTQ Orbitrap MS） method was developed for the simultaneous determination of 5 glucocorticoids residues,including dexamethasone,prednisone,hydrocortisone,methylprednisolone and tiramcinolone,in chicken muscle tissues.The QuEChERS pretreatment procedure was optimized.The chicken muscle samples were extracted with ethyl acetate and cleaned by PSA dispersive solid phase extraction.The separation of target compounds was performed on a Waters AQUITY UPLC HSS T3（2.1 mm×150 mm,1.8 μm） column by gradient elution using acetonitrile-water（containing 0.1% formic acid） as mobile phase at a flow rate of 0.25 mL/min.Identification of the glucocorticoids was based on the retention time and the exact mass of ［M+H］+ ions,and quantification of the glucocorticoids was based on the peak area of ［M+H］+ ions.The linear ranges of five compounds were in the range of 1-100 μg/L,with correlation coefficients more than 0.99.The average recoveries of 5 glucocorticoids at spiked levels of 5,10,20 μg/kg ranged from 87.5%to 119.7%,with relative standard deviations（RSDs） of 2.0%-11.0%.The limits of detection（LODs）of the method ranged from 0.49 μg/kg to 0.78 μg/kg,and the limits of quantitation（LOQs） ranged from 1.62 μg/kg to 2.57 μg/kg.The method was reliable and efficient,and could be applied in the determination of 5 glucocorticoids in chicken muscle samples. |