Sisco Edward, Burns Amber, Schneider Elizabeth, Miller Charles R, Bobka Laurel
National Institute of Standards and Technology, Gaithersburg, Maryland, USA.
Maryland State Police Forensic Sciences Division, Pikesville, Maryland, USA.
J Forensic Sci. 2022 Mar;67(2):471-482. doi: 10.1111/1556-4029.14936. Epub 2021 Nov 17.
As the challenges faced by drug chemists persist, due to the presence of emerging drugs, laboratories continue to look for new solutions, ranging from existing methods to implementation of entirely new technology. A common barrier for making workflow changes is a lack of pre-existing data demonstrating the potential impact of these changes. In this study, we compare, qualitatively and quantitatively, an existing workflow for seized drug analysis to an experimental workflow. Four chemists were asked to analyze a total of 50 mock case samples across the two workflows. The existing workflow employed color tests for screening alongside general purpose GC-FID and GC-MS analyses for confirmation. The experimental workflow combined DART-MS screening with class-specific (targeted) GC-MS analysis for confirmation. Comparison of the workflows showed that screening by DART-MS required the same amount of time as color tests but yielded more accurate and specific information. Confirmation using the existing workflow required more than twice the amount of instrument time and data interpretation time while also presenting other analytical challenges that prevented compound confirmation in select samples. Targeted GC-MS methods simplified data interpretation, reduced consumption of reference materials, and addressed almost all limitations of general-purpose methods. While the experimental workflow requires modifications and answering of additional research questions, this study shows how rethinking analytical workflows for seized drug analysis could reduce turnaround times, backlogs, and standards consumption. It also demonstrates the potential impact of being able to investigate workflow changes prior to implementation.
由于新型药物的出现，药物化学家面临的挑战依然存在，各实验室继续寻求新的解决方案，从现有方法到采用全新技术。改变工作流程的一个常见障碍是缺乏预先存在的数据来证明这些改变的潜在影响。在本研究中，我们对查获毒品分析的现有工作流程与实验性工作流程进行了定性和定量比较。四名化学家被要求在这两种工作流程中总共分析50个模拟案件样本。现有工作流程采用颜色测试进行筛选，并结合通用气相色谱 - 火焰离子化检测器（GC - FID）和气相色谱 - 质谱联用仪（GC - MS）分析进行确证。实验性工作流程将直接实时分析质谱（DART - MS）筛选与特定类别（靶向）GC - MS分析相结合进行确证。工作流程的比较表明，DART - MS筛选所需时间与颜色测试相同，但能产生更准确和具体的信息。使用现有工作流程进行确证所需的仪器时间和数据解读时间是原来的两倍多，同时还存在其他分析挑战，导致在某些样本中无法进行化合物确证。靶向GC - MS方法简化了数据解读，减少了参考材料的消耗，并解决了通用方法几乎所有的局限性。虽然实验性工作流程需要进行修改并回答其他研究问题，但本研究表明，重新思考查获毒品分析的分析工作流程如何能够减少周转时间、积压和标准品消耗。它还展示了在实施之前能够研究工作流程变化的潜在影响。
