基于分散固相萃取液相色谱-串联质谱法测定大米中8种真菌毒素

Determination of Eight Mycotoxins in Rice by Dispersive Solid Phase Extraction Coupled with Liquid Chromatography-Tandem Mass Spectrometry

建立了大米中HT-2毒素、T-2毒素、伏马毒素B1、伏马毒素B2、玉米赤霉烯酮、赭曲霉毒素A、脱氧雪腐镰刀菌烯醇和黄曲霉毒素B1共8种真菌毒素的快速测定方法。比较了3种基于分散固相萃取原理的样品前处理方法(即Qu ECh ERS方法、EMR-lipid方法以及Dis Qu E方法)对8种真菌毒素的回收率;以提取后加标法考察大米基质中各目标物LC-MS/MS分析的基质效应。结果表明,Qu ECh ERS样品前处理方法不适于伏马毒素B1、伏马毒素B2和赭曲霉毒素A分析;而EMR-lipid样品前处理方法无法消除玉米赤霉烯酮和赭曲霉毒素A在大米中的基质效应。据此采用Dis Qu E方法并优化LC-MS/MS分析参数,一次进样监测16对离子对(每个化合物2对离子对)分析大米中的8种真菌毒素残留量。8种真菌毒素在3个添加水平下的回收率为70.0%~124.1%,相对标准偏差为0.9%~16.9%,检出限(S/N≥3)为1.2~60.0μg/kg。该方法准确、灵敏,适用于大米中多种真菌毒素的快速分析。

A rapid method was developed for the determination of HT-2 toxin,T-2 toxin,fumonisin B1,fumonisin B2,zearalenone,ochratoxin A,deoxynivalenol and aflatoxins B1 in rice.Three dispersive solid phase extraction sample preparation methods,including QuEChERS method,EMR-lipid method and DisQuE method,were compared for the determination of 8 mycotoxins in rice.The recoveries of the three extraction methods for the toxins were studied.The method of after-extraction addition was used to evaluate the matrix effects for mycotoxins in rice by liquid chromatography-tandem mass spectrometry（LC-MS/MS）.As a result,the QuEChERS method was not suitable for the analysis of fumonisin B1,fumonisin B2 and ochratoxin A.The EMR-lipid methods could not overcome the matrix effects of zearalenone and ochratoxin A in rice.In this study,mycotoxins were extracted by DisQuE method,and analysed by LC-MS/MS under the optimized condition with monitoring 16 pairs of MS/MS transitions of precursor ions（two for each mycotoxin） in one single run.Recoveries at three fortified levels in rice ranged from 70.0% to 124.1% with relative standard deviations of 0.9%-16.9%.The limits of detection（S/N≥3） were in the range of 1.2-60.0 μg/kg.The method was proved to be highly efficient,robust and sensitive,and was suitable for the simultaneous analysis of mycotoxins in rice.