基于QuEChERS提取的超高效液相色谱-串联质谱法测定小麦粉中5种镰刀菌毒素

Determination of 5 Fusarium Mycotoxins in Wheat Flour by QuEChERS Extraction Combined with Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry

建立了小麦粉中恩镰孢菌素A、恩镰孢菌素A1、恩镰孢菌素B、恩镰孢菌素B1、白僵菌毒素5种镰刀菌毒素的超高效液相色谱-串联质谱(HPLC-MS/MS)分析方法。小麦粉样品采用改良的Qu ECh ERS方法进行提取,无需进一步净化,以甲醇-2 mmol/L乙酸铵为流动相梯度洗脱,经Agilent Eclipse Plus C_(18)色谱柱(2.1 mm×50 mm,1.8μm)分离,在电喷雾电离(ESI)正离子模式下采用多反应监测(MRM)进行测定,基质外标法定量。在较宽的线性范围内,5种镰刀菌毒素的相关系数(r2)均不小于0.993,方法检出限为0.3~0.8μg/kg,定量下限为0.8~2.4μg/kg。样品在1倍、2倍、10倍定量下限3个加标浓度下的平均回收率为74.0%~85.4%,相对标准偏差(RSDs)为5.6%~13.1%。采用建立的方法对市售的30批次小麦粉中5种镰刀菌毒素进行筛查,数批产品检出不同含量的镰刀菌毒素。该方法简单快速、准确、灵敏,可用于小麦粉中多种镰刀菌毒素的同时分析。

An ultra performance liquid chromatography-tandem mass spectrometric（UPLC-MS/MS） method was developed for the simultaneous determination of 5 fusarium mycotoxins in wheat flour,including enniatins A,enniatins A1,enniatins B,enniatins B1 and beauvericin.The fusarium mycotoxins were extracted from the samples using a modified QuEChERS-based extraction procedure without any further clean-up step.The separation of the analytes was carried out on an Agilent Eclipse Plus C18 column（50 mm×2.1 mm,1.8 μm） using the mobile phases of methanol and 2 mmol/L ammonium acetate by gradient elution.The detection was performed in the electrospray ion（ESI） positive mode and multiple reaction monitoring（MRM） mode.The matrix-matched calibrations were used to quantify the residue concentrations.The proposed method showed good linear relationship with correlation coefficients all above 0.993.The limits of detection（LODs）were in the range of 0.3-0.8 μg/kg,and the limits of quantitation（LOQs） were 0.8-2.4 μg/kg.The blank samples were fortified at three spiked levels（1 times,2 times,10 times of LOQ）,and the average recoveries ranged from 74.0% to 85.4% with relative standard deviations（RSDs） of 5.6%-13.1%.The developed method was successfully applied in analysis of fusarium mycotoxins in 30 samples bought from the market.The method was simple,rapid,accurate and sensitive,and was suitable for the simultaneous analysis of multi-fusarium mycotoxins in wheat flour.