Animal Drugs Research Center, U.S. Food and Drug Administration, Denver Federal Center, P.O. Box 25087, Denver, Colorado, USA.
Denver Laboratory, U.S. Food and Drug Administration, Denver Federal Center, Denver, Colorado, USA.
Rapid Commun Mass Spectrom. 2020 Apr 15;34(7):e8642. doi: 10.1002/rcm.8642.
A current trend in monitoring chemical contaminants in animal products is to use high-resolution mass spectrometry (HRMS). In this study, several HRMS data acquistion modes using Orbitrap MS for simultaneous full-scan MS in combination with MS2 analysis were evaulated for their effectiveness in detecting and identifying both targeted and non-targeted veterinary drug residues in aquacultured eel samples.
Sample preparation consisted of an acidic acetonitrile extraction with solid-phase extraction cleanup for analysis using LC/HRMS. Different data acquisition methods, including full-scan MS with non-targeted all ion fragmentation (AIF), multiplexed or variable data-independent analysis (mDIA or vDIA), targeted data-dependent MS2 (DDMS2), and parallel reaction monitoring (PRM) acquisition, were explored. The methods were evaluated with fortified eel tissue and imported eel samples to determine how many analytes could be detected and identified.
For non-targeted data acquisition, the number of analytes detected using DIA methods matched the results obtained by AIF, but the resulting product ion scans were more diagnostic because characteristic ions were predominant in the DIA MS2 spectra. In targeted analysis for a limited list of 68 compounds, full-scan MS followed by PRM was advantageous compared with DDMS2 because high-quality MS2 spectra were generated for almost all the analytes at target testing levels.
For residue screening, AIF has fast MS1 scan speed with adequate detection of product ions but may lead to false positive findings. DIA methods are better suited to monitor for both targeted and non-targeted compounds because they generate more characteristic MS2 spectra for retrospective library searching. For follow-up targeted analysis, PRM is prefered over DDMS2 when searching for a limited set of compounds.
目前监测动物产品中化学污染物的一个趋势是使用高分辨率质谱（HRMS）。在这项研究中，评估了几种使用 Orbitrap MS 进行同时全扫描 MS 结合 MS2 分析的 HRMS 数据采集模式，以评估其在检测和识别水产养殖鳗鱼样品中靶向和非靶向兽药残留的有效性。
样品制备包括酸性乙腈提取，固相萃取净化，用于 LC/HRMS 分析。探索了不同的数据采集方法，包括全扫描 MS 与非靶向全离子碎片化（AIF）、多重或可变数据独立分析（mDIA 或 vDIA）、靶向数据依赖 MS2（DDMS2）和平行反应监测（PRM）采集。使用加标鳗鱼组织和进口鳗鱼样品评估了这些方法，以确定可以检测和识别多少种分析物。
对于非靶向数据采集，DIA 方法检测到的分析物数量与 AIF 获得的结果相匹配，但得到的产物离子扫描更具诊断性，因为特征离子在 DIA MS2 谱中占主导地位。在针对 68 种化合物的有限列表进行靶向分析时，与 DDMS2 相比，全扫描 MS 后进行 PRM 具有优势，因为几乎所有目标测试水平的分析物都生成了高质量的 MS2 谱。
对于残留筛选，AIF 具有快速的 MS1 扫描速度和足够的产物离子检测，但可能导致假阳性结果。DIA 方法更适合监测靶向和非靶向化合物，因为它们为回溯库搜索生成更多特征 MS2 谱。对于有限化合物集的后续靶向分析，PRM 优于 DDMS2。
