基于自建数据库的超高效液相色谱-四极杆-飞行时间质谱法定量测定玉米中5种真菌毒素

Determination of 5 kinds of mycotoxins in Zea mays by ultra performance liquid chromatography-quadrupole-time-of-flight mass spectrometry based on self-established database

中文关键词:  超高效液相色谱-四极杆-飞行时间质谱  自建数据库 玉米  负离子真菌毒素?? 检验方法

英文关键词:Ultra-high  performance liquid  chromatography-Quadrupole-time-of-flight  mass spectrometry  self-built  database corn  mycotoxin method  confirmation

中文摘要:

      目的：应用超高效液相色谱－四极杆－飞行时间质谱（UPLC－Q－TOF/MS）自建数据库测定玉米中5种负离子真菌毒素方法。方法：Waters UPLC BEH C18色谱柱进行色谱分离后在Q－TOF/MS IDA负离子模式采集，绝对保留时间在0.5min内，加合物和碎片离子的精确质量匹配容差为5×10－6以内。SCIEX OS Explorer条件下确定5种负离子真菌毒素精确数据录入数据库。在玉米基质中以筛查检出限（SDL）作为主要参数验证方法。结果：在一定范围内5种负离子真菌毒素的检出限的范围为1.0～5.0ug/kg。Q-TOF-HRMS高分辨模式下我们采用加内标来改善基质干扰系数校正，提取同时添加法对真菌毒素在玉米基体中的基质效应θ进行评估,θ在0.84～1.10之间。基质匹配内标校准定量,5种负离子真菌毒素在范围内具有较好的线性关系，相关系数（r）为0.997～0.9993。玉米基质在低、中、高3个加标水平下的平均回收率为83.9％～106.8％和RSD%分别为2.39% ～11.37%。结论：内蒙部分地区100份玉米中5种负离子真菌毒素都有检出，有三份玉米中玉米赤霉烯酮超过100ug/kg限量标准，应引起相关监管部门重视。TEA和TEN检出率高达98.1和95.6%，为玉米中5种真菌毒素污染监测提供技术支持。

英文摘要:

      Five mycotoxins in maize were determined by ultra-high performance liquid chromatography-Quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) using a self-developed database. After separation on Waters UPLC BEH C18 column, the samples were collected in PLC-Q-TOF/MS IDA negative ion mode. The corresponding retention time (±0.2) and the exact mass matching tolerance of adduct ion and fragment ion were recorded as 5×10-6. A database of 5 mycotoxins was established in SCIEX OS Explorer in IDA mode. The detection limit of screening (SDL) was used as the main parameter to verify the screening method in maize matrix. The results showed that all five mycotoxins could be accurately screened at their limited levels, and their SDL ranged from 1.0 to 5.0 ug/kg. LC/MS/MS We added internal standard to improve the coefficient correction of matrix interference, IDMS correction factor θ evaluated the difference of matrix effect between the measured substance and its isotope diluent in the analysis, and the matrix effect (ME) was evaluated by extracting and adding method, with θ ranging from 0.84 to 1.08. The results showed that the five mycotoxins had a good linear relationship in their respective ranges, with correlation coefficients (r) ranging from 0.997 to 0.9993. The detection limits of the five mycotoxins ranged from 1.0 to 5.0ug/kg. The average recoveries were 83.9%-106.8% and RSDS were 2.39%-11.37% at low, medium and high levels, respectively. The results showed that five mycotoxins were detected in corn, three samples contained zearalenone more than 100ug/kg, and the detection rates of TEA and TEN were as high as 98.1 and 95.6%, which provided technical support for monitoring the pollution of five mycotoxins in corn.