Qi Dawei, Fei Ting, Liu Hong, Yao Heming, Wu Da, Liu Baizhan
Technology Center, Shanghai Tobacco Group Co. Ltd. , Changyang Road No. 717, Shanghai, 200082, P.R. China.
J Agric Food Chem. 2017 Nov 15;65(45):9923-9929. doi: 10.1021/acs.jafc.7b04329. Epub 2017 Nov 2.
The combination of multiple heart-cutting two-dimensional liquid chromatography (MHC-LC/LC) and quadrupole-orbitrap high-resolution mass spectrometry (HRMS) for simultaneous determination of the aflatoxins and ochratoxin A in snus is presented in this work. A C18 capillary column was used as the first dimension (1D) to isolate the aflatoxins and ochratoxin A from the complex matrices; then, a 2-position/10-port high-pressure valve equipped with two 60 μL loops was employed to transfer the heart-cuts of 1D-LC into a pentafluorophenyl (PFP) column for the second dimension (2D) separation. With the better separation of the MHC-LC/LC system, the sensitivity of the method was improved, which is essential for the trace mycotoxins analysis. Furthermore, HRMS performed in parallel reaction monitoring mode was employed to eliminate the interferences, and the sample pretreatment procedure was simplified. A new approach utilizing ethyl acetate with 1% formic acid/water solution was adopted to extract aflatoxins and ochratoxin A in snus, which provided parallel recoveries for aflatoxins and ochratoxin A with higher responses in comparison with the QuEChERS method. A dynamic range between 0.2 and 20 μg/kg was achieved with LOQs of 0.05 μg/kg for aflatoxin B, 0.1 μg/kg for aflatoxin B, G, G, and 1.0 μg/kg for ochratoxin A in dry mass of product. The results revealed that the established method exhibited good repeatability and recovery and could be used as a rapid and reliable approach for routine analysis of aflatoxins and ochratoxin A in snus.
本文介绍了采用多维中心切割二维液相色谱（MHC-LC/LC）与四极杆-轨道阱高分辨率质谱（HRMS）联用技术同时测定口含烟中黄曲霉毒素和赭曲霉毒素A的方法。使用C18毛细管柱作为第一维（1D），从复杂基质中分离黄曲霉毒素和赭曲霉毒素A；然后，采用配备两个60 μL定量环的二位十通高压阀，将1D-LC的中心切割馏分转移至五氟苯基（PFP）柱进行第二维（2D）分离。由于MHC-LC/LC系统具有更好的分离效果，该方法的灵敏度得到提高，这对于痕量霉菌毒素分析至关重要。此外，采用平行反应监测模式的HRMS消除干扰，并简化了样品前处理程序。采用乙酸乙酯与1%甲酸/水溶液的新方法提取口含烟中的黄曲霉毒素和赭曲霉毒素A，与QuEChERS方法相比，该方法对黄曲霉毒素和赭曲霉毒素A的回收率相当，响应更高。在产品干质量中，黄曲霉毒素B1的定量限为0.05 μg/kg，黄曲霉毒素B2、G1、G2的定量限为0.1 μg/kg，赭曲霉毒素A的定量限为1.0 μg/kg，实现了0.2至20 μg/kg的动态范围。结果表明，所建立的方法具有良好的重复性和回收率，可作为口含烟中黄曲霉毒素和赭曲霉毒素A常规分析的快速可靠方法。
