凝胶渗透色谱串联气相色谱-质谱法测定鲜食用菌中25种农药残留

Determination of 25 pesticide residues in edible fresh mushroom by GPC-GC-MS

目的建立蘑菇中25种农药残留的在线凝胶渗透色谱-串联三重四极杆气质联用法。方法样品用乙腈超声提取,提取液经Qu ECh ERS小柱净化,氮吹浓缩后经凝胶渗透色谱(GPC)在线净化。采用DB-5MS(30 m×0.25 mm,0.25μm)色谱柱进行气相色谱-质谱(GC-MS)分析,以外标法定量。结果 25种农药在其浓度范围内均呈现良好的线性关系,线性相关系数(r)≥0.998 0,方法的检出限(LOD)为0.000 3 mg/kg^0.003 0 mg/kg,定量限(LOQ)为0.001 mg/kg^0.010 mg/kg。方法的加标回收率为73.1%~114.0%,相对标准偏差(RSD)为2.14%~8.32%。结论该方法的样品前处理简单,分析时间短,灵敏度和精密度均符合农药残留检测技术的要求,适用于食用菌中多种农药残留的检测。

Objective To develop a method for determination of 25 pesticides in edible fresh mushroom by gel permeation chro- matographic clean - up coupled with gas chromatography - triple quadrupole mass spectrometry （ GPC - GC - MS）. Methods The samples were extracted with a^etonitrile under ultrasonic operation, and the extract was first cleaned up with QuEChERS extraction column, and then concentrated by nitrogen gas, cleaned up with the on -line GPC system. The DB -5MS column（30 m ×0.25 mm,0.25 μm） was used for GC -MS analysis, and external standard method was used for quantification. Results The method showed good linearity in the concentration range of 25 pesticedes （r ≥ 0. 998 0）. The detection limit of the method （LOD） was in the range of 0. 000 3 mg/kg - 0. 003 0 mg/kg. The quantification limit of it （LOQ） was in the range of 0.001 mg/kg-0. 010 mg/kg. The recovery rate was 73. 1% - 114.0% with the relative standard deviations （RSDs） of 2.14% - 8.32%. Conclusion This method was simple on pretreatment and rapid on detection. Its sensitivity and accuracy could meet the requirements for the analysis of multiple pesticide residues in edible fresh mushroom.