Determination of Clotrimazole Residue in Animal-Derived Food by Gas Chromatography-Tandem Mass Spectrometry with Isotope Dilution

An isotope dilution gas chromatography-tandem mass spectrometry(GC-MS/MS)method for the determination of clotrimazole residues in animal-derived food(Pork,chicken,pig fat,pig heart,pig liver,pig kidney)was established. The samples were extracted with accelerated solvent extraction,and cleaned up by gel permeation chromatography. HP-5 MS chromatographic column(30 m×0.25 mm×0.25 μm)was used for separation,multi-reaction monitoring(MRM)mode detection,and isotope internal standard method for quantification. Results showed that there was a good linearity for clotrimazole in the range of 1~100 μg/L with a correlation coefficient(R²)of 0.9995. The limit of quantitation(LOQ,S/N≥10)of the method was 2.0 μg/kg. The average recoveries at three spiking levels(2.0,5.0,20.0 μg/kg)were 82.6%~116.5%. Relative standard deviation(RSD)were 5.2%~13.5%. This method has high sensitivity and accuracy,and can be used for the confirmation and quantitative analysis of clotrimazole residues in animal-originated foodstuffs.