Abstract:
A method for the simultaneous determination of 45 pesticide residues in apple by QuEChERS-gas chromatography-mass spectrometry was established. Apple samples were extracted by acetonitrile containing 1%(V%)acetic acid,and purified by 25 mg PSA,25 mg C
18 and 7.5 mg GCB. And detected in GC-MS selective ion monitoring(SIM)mode,and quantitatively analyzed with the matrix-matched external standard calibration curves. Test results showed that the 45 pesticides had good linearity in the range from 10~200 μg/L,and the determination coefficients of pesticides were greater than 0.995. The average recovery ranges were mainly between 69.3% and 116% at the three spiked concentration levels(30,50,100 μg/kg),and the relative standard deviations were between 0.7% and 7.9%. The LOD(limit of detection)was from 1.5 to 15.0 μg/kg,and LOQ(the limit of quantification)was from 5.0 to 50.0 μg/kg.The method is accurate,precise,simple,fast and economic. It is suitable for the detection of pesticide residues in apples.