GC-MS同时测定霍山石斛及霍山产铁皮石斛中拟除虫菊酯和氨基甲酸酯类16种农药残留的检测方法

Simultaneous Determination of 16 Kinds of Pyrethroid and Carbamate Pesticide Residues in Dendrobium huoshanense and Dendrobium officinale from Huoshan by GC-MS

建立了气相色谱-质谱(GC-MS)联用法同时测定霍山石斛及霍山产铁皮石斛中16种农药残留的分析方法。石斛样品经乙腈提取,减压浓缩后,采用SPE固相萃取法和QuEChERS法净化,GC-MS采用选择离子测试(SIM)模式进行检测。结果表明,16种农药在5.0～80.0μg/mL浓度范围内呈现良好的线性关系,使用SPE固相萃取法在500μg/L加标水平下各农药的加标回收率为84.87%～95.96%,相对标准偏差(RSD)为4.08%～7.66%,当使用QuEChERS法在500μg/L加标水平下各农药的加标回收率为94.90%～104.91%,相对标准偏差(RSD)为2.23%～4.67%,且QuEChERS法加样回收率和相对标准偏差略优于SPE固相萃取法。16种农药残留定量限为0.0003～0.2331μg/mL,精密度(RSD)为1.02%～2.58%,稳定性(RSD)为1.82%～2.97%。该方法快速、灵敏、准确,可应用于霍山石斛及霍山产铁皮石斛中多种农药残留的测定。

Gas chromatography-mass spectrometry(GC-MS)method for the simultaneous determination of 16 pyrethroid and carbamate pesticide residues in Dendrobium huoshanense and Dendrobium officinale from Huoshan was developed.The samples were extracted with acetonitrile.After being vacuum concentrated,the extract was purified by using SPE and QuEChERS pretreatments.GC-MS was tested by selective ion mode(SIM).The results showed that the working curves for 16 pesticides were linear in the range of 5.0~80.0μg/mL.The SPE pretreatment recoveries of 16 pesticides at spiked level of 500μg/L were 84.87%~95.96%,and relative standard deviations(RSD)were 4.08%~7.66%.The QuEChERS pretreatment recoveries of 16 pesticides at spiked level of 500μg/L were 94.90%~104.91%,and relative standard deviations(RSD)were 2.23%~4.67%.The QuEChERS methods was slightly better than SPE about recoveries and relative standard deviations.The limits of quantitation were 0.0003~0.2331μg/mL,the precision and stability were 1.02%~2.58%and 1.82%~2.97%,respectively.This method was rapid,sensitive and accurate and it could meet the demands for the determination of multi-pesticides in D.huoshanense and D.officinale samples from Huoshan.