建立了QuEChERS-改性多壁碳纳米管提取净化结合液相色谱-质谱联用同时检测新会陈皮中6种真菌毒素和3种农药残留的分析方法,并对影响提取、净化、检测效率的因素进行了优化.以乙腈-水(80∶20)提取样品,适量改性多壁碳纳米管净化后,净化液直接用HPLC-MS/MS进行测定,选择多反应监测模式,基质匹配标准溶液外标法定量.在优化实验条件下,9种目标化合物在各自线性范围内均具有良好的线性关系,相关系数为0.983 8 ～0.998 2,检出限(S/N =3)为0.18 ～ 10μg/kg.在低、中、高3个加标水平的平均回收率为72.4％～ 106％,相对标准偏差为2.2％ ～ 7.4％.该法准确、灵敏度高、操作简单、快速,可满足新会陈皮中上述9种化合物同时测定的要求,应用于真菌毒素和农药残留的快速筛查和确证,结果满意.%An analytical method based on QuEChERS with modified multiwalled carbon nanotubes (MWNTs) as adsorbent was developed.The determination of 6 mycotoxins and 3 pesticides residues,including 2,4-D,methomyl,chlorpyrifos,AFG2,AFG1,AFB2,AFB1,OTA and ZEN in xinhui dried orange peel was carried out by liquid chromatography-tandem mass spectrometry (LC-MS/MS).The factors affecting the extraction,purification and detection efficiency were optimized,and the optimal conditions were as the following:the samples were extracted with acetonitrile-water (80 ∶ 20) mixed solution,and purified by QuEChERS method with modified MWNTs as adsorbent.The separation was performed on a Shimadzu C1s(150 mm ×2.1 mm ×3.5 μm) column,then determined by LC-MS/MS under multiple reaction monitoring(MRM) mode and quantified by external standard method with the matrix-matched standards solution.Under the optimized conditions,the calibration curves of 9 compounds were linear in the respective concentration ranges with correlation coefficients of 0.983 8-0.998 2.The detection limits(S/N =3) were in the range of 0.18-10 μg/kg.The recoveries at low,medium and high spiked levels ranged from 72.4％ to 106％,with relative standard deviations of 2.2％-7.4％.With the advantages of accuracy,high sensitivity,easy operation and rapidness,the method was suitable for the simultaneous determination of mycotoxins and pesticide in xinhui dried orange peel,and was applied in the rapid screening of toxic and harmful substances in foods with satisfactory results.
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