QuEChERS-气质联用仪测定喀什石榴中70种农药残留

Determination of 70 kinds of pesticide residues in Kashi pomegranate by QuEChERS-gas chromatography-triple quadrupole mass spectrometry

建立喀什石榴中70种农药残留的快速测定方法。3个品种喀什石榴经优化后的QuEChERS技术提取和净化,根据70种农药残留特征碎片离子建立气质联用条件,在多反应监测模式下进行检测,基质匹配外标法定量分析。结果表明,在0~1.0μg/mL质量浓度范围内,线性关系良好(R^(2)>0.995),检出限为0.005~0.02 mg/kg。当添加量为0.01 mg/kg时,回收率为76.4%~108%,相对标准偏差为0.6%~10.4%(n=5);当添加量为0.05 mg/kg时,回收率为75.4%~107%,相对标准偏差为1.4%~11.2%(n=5);当添加量为0.1 mg/kg时,回收率为71.6%~108%,相对标准偏差为0.2%~9.7%(n=5)。该方法简便、快捷,溶剂消耗量少,灵敏度高,适用于喀什石榴类多色素含糖量高,干扰大的样品中农药残留检测。

To establish a method for the simultaneous determination of 70 kinds of pesticide residues in three varieties of Kashi pomegranate by QuEChERS-gas chromatography-triple quadrupole mass spectrometry.Three varieties of Kashi pomegranate were extracted and purified by optimized QuEChERS procedure,gas-mass spectrometry conditions were established based on the characteristic fragment ions of 70 pesticide residues.The detection was carried out in multiple reaction monitoring mode,and the matrix matching external standard method was used for quantitative analysis.The results showed that the 70 kinds of pesticide residues had a good linear relationship in the range of 0-1.0μg/kg,and the correlation coefficient was greater than 0.995.The limit of detection was 0.005-0.02 mg/kg.Totally 70 pesticide residues ranged from 76.4%to 108%in 0.01mg/kg;ranged from 75.4%-107%in 0.05 mg/kg;ranged from 71.6%-108%in 0.1mg/kg.The relative standard deviation(RSD)was 0.2%-11.2%(n=5)and the difference was statistically significant(P<0.05).This method is easy,simple,fast,efficient and has good repeatability and stability,which can be used for the quantitative detection and qualitative identification of pesticide residues in multi pigment sample such as Kashi pomegranate with high sugar content and large interference.