咖啡中3种赭曲霉毒素QuEChERS-UPLC-MS/MS检测方法

Establishment of QuEChERS-UPLC-MS/MS method to determine three kinds of ochratoxins in coffee

目的:建立同时测定咖啡中3种赭曲霉毒素的QuEChERS-超高效液相色谱—串联质谱检测方法。方法:样品经乙腈—水—甲酸(V_(乙腈)∶V_(水)∶V_(甲酸)为55∶40∶5)超声提取,利用QuEChERS盐包进行脱水盐析,过ZanChERS-Myco17净化小柱净化。样品采用0.2%甲酸水—乙腈作为流动相经Waters BEH C_(18)(1.7μm,2.1 mm×100 mm)色谱柱梯度洗脱分离。电喷雾正离子模式,多反应监测扫描,内标法定量。结果:3种目标物在0.1~20.0 ng/mL的质量浓度范围内线性关系良好,相关系数≥0.99946,方法检出限和定量限分别为0.1~0.2,0.2~0.7μg/kg。咖啡基质中3个添加水平目标物平均回收率为79.0%~103.3%,相对标准偏差为1.5%~7.6%。结论:该方法前处理简单,重现性好,分析时间短,能够适用于不同咖啡基质样品中3种赭曲霉毒素残留的高通量检测。

Objective:A new method was developed for the simultaneous determination of three kinds of ochratoxins in coffee by ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS)combined with QuEChERS pretreatment.Methods:Samples were extracted by acetonitri-water-formic acid solution(55∶40∶5)with ultrasonic,salted out with a QuEChERS salt pocket,and then purified with a(ZanChERS-Myco17)column.The chromatographic separation was performed on an ACQUITY UPLC BEH C_(18)(1.7μm,2.1 mm×100 mm)column by gradient elution using a mobile phase comprising 0.2%formic acid aqueous solution and acetonitrile.In the positive ion mode of electric spray,the samples detected were used by multiple reaction monitoring(MRM)modes with internal standard method.Results:Three target substances had a good linear relationship in the range of 0.1~20.0 ng/mL,and the correlation coefficient was greater than 0.99946.The detection limit and quantitative limit were 0.1~0.2μg/kg and 0.2~0.7μg/kg,respectively.Average recoveries at three spiked levels in the coffee matrix were 79.0%~103.3%with a relative standard deviation of 1.5%~7.6%.Conclusion:This method has the advantages of simple sample pretreatment,good reproducibility and high efficiency,and is suitable for the high-throughput detection of multiple ochratoxins in different coffee samples.