免疫亲和柱在植物油农残检测前处理中的应用研究

Application of IAC in pretreatment for determination of organophosphorus pesticide residues in vegetable oil

建立了一种快速有效净化植物油中有机磷农药残留的检测方法。以不同有机试剂对植物油样品中有机磷农药进行提取,经冷冻离心后,取上清液采用多功能免疫亲和柱(MycoSep 226 AflaZon+)净化,收集净化液经浓缩、定容后采用气相色谱测定,外标法定量。以13种有机磷农药回收率为指标对丙酮、正己烷、乙腈3种提取剂及均质、涡旋和超声3种提取方式进行了筛选。结果表明:提取剂以乙腈的效果最好,回收率为81.3%~101.5%;均质、涡旋和超声3种提取方式的回收率均在76.6%以上,均质和涡旋的回收率均能达到81%以上,其中以涡旋更为便捷;在0.02~0.50 mg/L范围内,13种有机磷农药的回归方程线性关系良好,相关系数(R2)均大于等于0.999,检出限为0.005~0.010 mg/kg;0.04、0.08、0.20 mg/kg低、中、高添加量的平均加标回收率为80.3%~102.1%,相对标准偏差小于等于3.93%。本方法具有提取剂用量小,检测结果准确度高,对检测设备污染小,过柱净化操作简单,1 min内即可完成等特点,适用于植物油中有机磷农药残留的批量检测。

A fast and effective method was established for the cleanup of organophosphorus pesticide residues in vegetable oil. Organophosphorus pesticides in vegetable oil samples were extracted with different organic reagents. After freezing and centrifugation,the supernatant was purified by multi-functional immunoaffinity column( MycoSep 226 AflaZon +). The concentrated liquid was determined by gas chromatography and quantified by external standard method. Three kinds of extraction reagents such as acetone,n-hexane and acetonitrile,and three extraction methods such as homogenization,vortex and ultrasound were screened by the recovery index of 13 organophosphorus pesticides pesticides. The results showed that acetonitrile was the best extraction reagent with the recovery of 81. 3%-101. 5%. The recoveries of three extraction methods were all above 76. 6%,and the recoveries of homogenization and vortex were all above 81%. Among them,vortex was more convenient. The linear relationship of 13 organ-ophosphorus pesticides regression equation was good in the range of 0. 02-0. 50 mg/L,and the correlation coefficient( R2) was not lower than 0. 999. The detection limit was 0. 005-0. 010 mg/kg. The average recoveries of low,medium and high standard additions of 0. 04,0. 08 mg/kg and 0. 20 mg/kg were 80. 3%-102. 1%,and the RSD was not more than 3. 93%. This method had the characteristics of saving reagents,high detection accuracy,low pollution,simple operation of column purification completed within 1 min. The method extablished was suitable for batch detection of organophosphorus pesticide residues in vegetable oil.