芦蒿中5种拟除虫菊酯农药残留的测定

摘要:目的　建立一种测定芦蒿中拟除虫菊酯类农药残留测定的方法。方法　芦蒿样品分别经QuEChERS法和固相萃取（SPE）法处理后，结合气相色谱-电子捕获检测器（GC-ECD）对芦蒿中5种拟除虫菊酯农药残留进行测定分析。结果　5种农药在30 min内得到很好的分离，在10.0 μg/kg～5000 μg/kg浓度范围内线性关系良好（r＞0.999），最低检出浓度为0.2 μg/kg～4.5 μg/kg。在加标100 μg/kg～200 μg/kg浓度范围内，QuEChERS平均加标回收率为23.0%～42.4%，相对标准偏差（RSD）为10.8%～26.9%；SPE法平均加标回收率为70.7%～98.9%，相对标准偏差分别为1.7%～8.9%（＜10%）（n＝5）。结论　QuEChERS法虽前处理简单、方便，但加标回收率低，相对偏差大，而SPE法虽样品处理过程费时，但加标回收率高，相对偏差小，是芦蒿中拟除虫菊酯类农药残留的首选方法。

Determination of five common pyrethroid pesticides residues in artemisia selengensis by gas chromatography

Abstract: Objective To establish a gas chromatography (GC) method for the determination of pyrethroid pesticides residues in Artemisia selengensis. Methods Artemisia selengensis samples were pre-treated by QuEChERS method and solid phase extraction (SPE) method. Then GC-ECD was adopted to detect and analyze the residues of five common pyrethroid pesticides in the samples. Results The five pyrethroid pesticides were separated well in 30 minutes and the linear range were 10.0 ～5000 μg/kg (r>0.999). The limits of detection varied from 0.2 to 4.5 μg/kg. 100～200 μg/kg standards were spiked in the samples, and the average spiked recoveries of QuEChERS method ranged from 23.0% to 43.1%, with a RSD between 5.5% to 26.9%. The average spiked recoveries of SPE method ranged from 70.6% to 98.5%, with a RSD between 1.6% to 8.1% (<10%) (n=5). Conclusion The QuEChERS method was simple and convenient, but the recovery rate was low and RSD was high. The method of processing is time-consuming, but both the recovery rate was high and the RSD were low. So the SPE method is much better than QuEChERS in determining pyrethiod pesticides residues in artemisia selengensis samples.