磁性固相萃取液质联用法测定植物油中的黄曲霉毒素

Determination of aflatoxins in vegetable oil by liquid chromatography-mass spectrometry with magnetic solid phase extraction

目的建立基于磁性多壁碳纳米管的磁性固相萃取结合高效液相色谱串联质谱测定植物油中黄曲霉毒素的方法。方法样品加入正己烷后,用pH为3.0、体积分数为12.5%的乙腈-水溶液提取,而后加入MWCNTs-Fe3O4进行磁性固相萃取。对影响磁性固相萃取的条件如萃取剂、吸附剂用量、吸附时间、洗脱剂、洗脱时间等进行优化。结果黄曲霉毒素AFB1、AFB2、AFG1和AFG2在其线性范围内线性关系良好,相关系数均大于0.994,方法检出限为0.02~0.05μg/kg,定量限为0.08~0.15μg/kg。在0.10、1.00和5.00μg/kg 3个添加水平下,4种黄曲霉毒素平均回收率在75.1%~96.5%之间,相对标准偏差在3.2%~6.2%之间。结论该方法简便、快速、高效、准确,可用于植物油中黄曲霉毒素的检测。

Objective To establish a method for the determination of aflatoxin in vegetable oil by magnetic solid phase extraction combined with high performance liquid chromatography-tandem mass spectrometry based on magnetic multi-walled carbon nanotubes.Methods After adding n-hexane,the samples were extracted with acetonitrile-water solution with pH of 3.0 and volume fraction of 12.5%,then MWCNTs-Fe3O4 was added for magnetic solid phase extraction.The conditions affecting magnetic solid phase extraction were optimized,such as extractant selection,the amount of MWCNTs-Fe3O4,adsorption time,eluent solvent selection and eluent time.Results Aflatoxin AFB1,AFB2,AFG1 and AFG2 showed good linear relationship within their linear range,and the correlation coefficients were all higher than 0.994 The limits of detection and the limits of quantitation of pesticides were in the range of 0.02‒0.05μg/kg and 0.08‒0.15μg/kg,respectively.The average recoveries at spiked levels of 0.10,1.00,5.00μg/kg ranged from 75.1%‒96.5%with relative standard deviations between 3.2%‒6.2%.Conclusion This method is simple,fast,efficient and accurate,which could be applied to the determination of aflatoxin in vegetable oils..