Identification and Quantification of 22 Benzodiazepines in Postmortem Fluids and Tissues using UPLC/MS/MS

Civil Aerospace Medical Institute2018PDFTech ReportAngier, Michael K.Saenz, Sunday R.Ritter, Roxane M.Lewis, Russell J.United States. Department of Transportation. Federal Aviation Administration. Office of Aviation. Civil Aerospace Medical InstituteUnited States. Department of Transportation. Federal Aviation Administration. Office of Aviation. Office of Aerospace MedicineUnited States. Department of Transportation. Federal Aviation Administration. Office of Aviation. Civil Aerospace Medical InstituteUnited StatesForensic medicineToxicologyDrug effectsChemical analysisBlood analysisNarcoticsForensic toxicologyPostmortemLC/MS/MSBenzodiazepinesDOT/FAA/AM-18/01FinalBenzodiazepines, a class of drugs known to cause central nervous system depression, are widely prescribed for a variety of different medical conditions such as anxiety, insomnia, and as a preoperative sedative in conjunction with anesthesia. In fact, four are listed in the top 100 most prescribed drugs. Although there are many medicinal benefits with benzodiazepines, there are many impairing side effects that can impact the ability to safely operate an aircraft. Therefore, the Federal Aviation Administration's Forensic Toxicology Research Team has developed and validated a comprehensive method for the analysis of 22 benzodiazepines in postmortem fluids and tissues. The newly developed method uses ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC/MS/MS) and a single step crash-and-shoot extraction. This new method reduces extraction time, significantly reduces sample volume, and eliminates derivatization steps necessary for commonly employed methods involving solid-phase extraction and GC/MS. For each of the analytes, the linear dynamic range encompasses sub-therapeutic to toxic concentrations. This method proved to be accurate and reproducible with control values not exceeding 20% of the target concentration. Analytes were stable over a 5-day period when stored at 4\ub0C as well as on instrument, post extraction. Additionally, all analytes were stable after three freeze/thaw cycles. Ion suppression was evaluated in a variety of postmortem fluids and tissues. Although there was minimal suppression in fluids, there was suppression observed in tissues. However, this suppression affected the internal standard similarly; therefore, quantitative reliability was maintained. This newly developed UPLC/MS/MS method has been proven to be accurate and precise in the identification and quantification of 22 benzodiazepines in postmortem fluids and tissues.115