气相色谱法测定坚果中8种拟除虫菊酯农药残留

建立了东盟进口坚果夏威夷果、开心果、杏仁中8种拟除虫菊酯农药残留的检测方法。样品采用乙腈作萃取溶剂超声波提取,经中性氧化铝串联弗罗里硅土小柱净化,组分经不同极性的两根毛细管柱进行分离,采用气相色谱法以ECD检测器检测坚果中8种拟除虫菊酯农药。该方法在0.01~1.0μg/m L浓度范围内具有良好的线性关系,相关系数为0.999 2~0.999 9;在农药添加浓度为10,20,50μg/kg时,回收率为71%~115%,相对标准偏差为4.5%~9.8%,检出限(LOD,S/N=3)为0.014~0.28μg/kg,定量下限(LOQ,S/N=10)为0.047~0.94μg/kg。该方法分离效果好,准确可靠,回收率高,方便快速,可用于坚果中农药残留的日常检测。

Determination of 8 Pyrethroid Pesticide Residues in Nuts by Gas Chromatography

An analytical method was developed for the determination of 8 pyrethroid pesticide residues in nuts (hawaii nuts,pigeon nuts,almonds imported from ASEAN).The samples were extracted with acetonitrile by ultrasonic technique,purified with Alumina-N SPE and Florisil SPE.The components were separated with two different polarity capillary columns,and 8 kinds of pyrethroid pesticide residues were detected by GC with ECD detector.The linear range of the method was in the range of 0.01-1.0 μg/mL(r =0.999 2-0.999 9).The recoveries at three spiked concentrations of 10,20,50 μg/kg were in the range of 71％-115％,with relative standard deviations(RSD) of 4.5％-9.8％.The limits of detection(LOD,S/N =3) were in the range of 0.014-0.28 μg/kg.The limits of quantitation(LOQ,S/N =10) were in the range of 0.047-0.94 μg/kg.The established method has the advantages of good separation,high accurancy,high recovery,convenience and rapidness,and could be used for the routine analysis of pesticide residues in nuts.