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目的通过优化气相色谱和质谱条件,建立采用固相萃取(SPE)净化结合气相色谱-质谱法同时分析果蔬中27种农药残留的方法。方法样品匀浆后用乙腈超声提取盐析过滤,氮气吹干后用丙酮二氯甲院(1:1)复溶经无水硫酸钠过滤后,Cleanert PC/NH_2-SPE固相萃取柱净化氮吹浓缩正己烷定容。采用TG-5MS毛细管柱和质谱检测器测定内标法定量。结果 27种农药在50 min内完全分离在0.05~1.5 mg/L范围内线性良好相关系数R~2均>0.998,检出限为0.14~9.84μg/kg,平均加标回收率在77.6%~114.2%范围,相对标准偏差2.19%~9.18%。结论所建立的方法背景干扰少,净化效果好,简便、快速具有较高的准确度与精密度适用于果蔬中农药残留的测定。
Objective To establish a method for the simultaneous analysis of 27 pesticide residues in fruits and vegetables by using solid phase extraction (SPE) and gas chromatography-mass spectrometry (GC-MS) by optimizing GC and MS conditions. Methods After the sample was homogenized, the sample was extracted with acetonitrile by sonication and salting-out. The filtrate was purified by acetone on a Cleanert PC / NH_2-SPE solid phase extraction column after being dried in nitrogen and reconstituted with acetone and dichloromethane (1: 1) Concentrate n-hexane concentrate. The internal standard method was used for the determination of TG-5MS capillary column and mass spectrometry detector. Results The linear correlation coefficients (R ~ 2) were all 0.998 and the limits of detection were 0.14 ~ 9.84μg / kg. The average recoveries of the 27 pesticides within 50 min were between 77.6% ~ 114.2% range, relative standard deviation 2.19% ~ 9.18%. Conclusion The established method has less background interference, good purification effect, simple and rapid, high accuracy and precision for the determination of pesticide residues in fruits and vegetables.