QuEChERS结合UPLC-Q/Orbitrap HRMS法测定小麦粉中9种真菌毒素

Determination of Nine Mycotoxins in Wheat Flour by QuEChERS-Ultra-high Performance Liquid Chromatography Quadrupole/Orbitrap High-Resolution Mass Spectrometry

建立QuEChERS-高效液相色谱-四极杆/静电轨道离子阱高分辨质谱法同时测定小麦粉中9种真菌毒素的方法。样品经2.0%甲酸-乙腈提取,QuEChERS盐包脱水盐析后,用dSPE净化管净化,超高效液相色谱分离,在正离子模式下进行检测。在全扫描模式下测定目标化合物的一级精密质量数,与理论精密质量数相比,相对偏差不大于1.91×10^(-6),可实现精准定性;同时建立了9种真菌毒素的二级质谱数据库,实现对9种真菌毒素的定性筛查及同步定量。9种真菌毒素线性范围为0.25~100μg/L,定量限范围为0.30~3.00μg/kg,在低、中、高3个不同添加水平下的平均回收率为70.2%~112.0%,相对标准偏差为0.2%~4.5%。该方法可作为小麦粉中真菌毒素的高通量筛查和确认检测方法。

A method was developed for the simultaneous determination of nine mycotoxins in wheat flour by ultra-high performance liquid chromatography-quadrupole/orbitrap high-resolution mass spectrometry(UPLC-Q/Orbitrap HRMS)combined with QuEChERS(quick,easy,cheap,effective,rugged and safe)pretreatment.Samples were extracted with acetonitrile/formic acid solution(98.0:2.0,V/V),salted out with a QuEChERS salt pocket,and then purified with a dispersive solid phase extraction(dSPE)tube.The target compounds were separated by UPLC and detected in the positive ion mode.Measured accurate mass-to-charge ratios of the nine mycotoxins were obtained in the full scan mode with a relative deviation not more than 1.91×10^(-6) compared to the theoretical value,indicating accurate qualitative analysis of these compounds.A tandem mass spectral library for simultaneous screening and quantitation of the mycotoxins was built based on characteristic fragment ions.The linear ranges were 0.25–100μg/L for all target analytes.The limit of quantification(LOQ)ranged from 0.30 to 3.00μg/kg.Average recoveries at three spiked levels were in the range of 70.2%-112.0%with relative standard deviation(RSD)of 0.2%–4.5%.This method is useful for the high-throughput screening and confirmation of mycotoxins in wheat flour.