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Confirmation of Carfentanil, U-47700 and Other Synthetic Opioids in a Human Performance Case by LC-MS-MS
1Department of Pathology and Laboratory Medicine, University of Miami Miller School of Medicine, Rosenstiel Medical Science Building (RMSB), 1600 NW 10th Avenue, 7th Floor Suite 7020 (R-5), Miami, FL 33136, USA.
Abstract:
Recently, it has been documented that there has been a rise in synthetic opioid abuse. Synthetic opioids are compounds that were created to act as agonists for the opioid receptors. Like synthetic cannabinoids, most of these compounds were created by research groups or pharmaceutical companies in an attempt to find compounds that have medicinal use. Synthetic opioids have severe health implications when abused that can include hospitalization and death. Due to the high potency and the low dose required to produce the desired effects for these compounds, it was hypothesized that they may not be detectable in human performance case samples. However, this report documents a male driver who was involved in a single-vehicle incident. First responders treated the subject with naloxone as opioid drug impairment was suspected and he was transported to the local emergency room. The subject consented to a blood draw for a driving under the influence (DUI) investigation. Initial routine testing identified alprazolam at 55 ng/mL and fentanyl at less than 0.5 ng/mL. Further testing using a validated liquid chromatography-tandem mass spectrometry (LC-MS-MS) assay, confirmed the presence of carfentanil, furanyl fentanyl, para-fluoroisobutyryl fentanyl, U-47700 and its metabolite. To the author's knowledge, this is the first report of a DUI cases where carfentanil, U-47700 and other synthetic opioids were confirmed and described in a human performance blood sample. This case demonstrates the need to supplement routine toxicological analyses with a sensitive methodology that can detect synthetic opioids in human performance cases where opioid use may be implicated.

