GC-NCI-MS快速检测食用菌中菊酯类农药

Determination of Pyrethroid Pesticides Residue in Edible Fungus by Gas Chromato-graphy-negative Chemical Ionization-Mass Spectrometry

建立了气相色谱-负化学离子化质谱法(GC-NCI-MS)快速检测食用菌中6种拟除虫菊酯农药残留量的分析方法。前处理对QuECHERS方法进行优化,样品用含0.5%乙酸的乙腈溶液提取,PSA吸附剂净化,GC-NCI-MS选择离子监测(SIM)方式对6种菊酯类农药进行检测。结果表明:6种拟除虫菊酯农药在0.007～5.0mg/L的浓度范围内线性良好,相关系数为0.999 2～0.999 9;最低检测浓度为1～3mg/kg;添加浓度为0.05mg/kg时,平均回收率为87.0～103.6%,变异系数为3.2～17.3%;添加浓度为0.1mg/kg时,平均回收率为82～99%,变异系数为2.1～14.5%。

A determination of 6 pyrethroid pesticides residue in edible fungus was developed by gas chromatography-mass spectrometry operated in negative-ion chemical ionization mode （GC- NCI-MS） . The samples were pretreated by using a modified QuEChERS method. Acetonitrile containing 0.5% acetic acid was used as extraction solvent. The extracts were analyzed by GC- NCI-MS after being subjected to a simple clean-up procedure using PSA. The results showed that the calibration linear for 6 pyrethroid pesticides range from 0.007mg/L to 5.0mg/L with a correlation coefficient of 0.999 2 ~0.999 9.The LODs range from llxg/kg to 3lxg/kg.Average recoveries spiked at the levels of 0.05 mg/kg ranged from 87% to 103.6%, the relative standard deviations were between 3.2% ranged from 82% to 99%, the and 17.3%. Average recoveries relative standard deviations were spiked at the levels of 0.1mg/kg between 2.1% and 14.5%.