{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T22:37:16Z","timestamp":1790203036991,"version":"4.1.0"},"reference-count":50,"publisher":"Oxford University Press (OUP)","issue":"9","license":[{"start":{"date-parts":[[2024,9,2]],"date-time":"2024-09-02T00:00:00Z","timestamp":1725235200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2024,11,15]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p>In recent years, the use of 2-benzylbenzimidazole opioids (\u2018nitazenes\u2019) has increased with them becoming one of the most prominent synthetic opioid subclasses of novel psychoactive substances. With the increased prevalence, there is also a concern of the dangers to public health with the use of nitazenes due to their high potency especially with polypharmacy. To aid in the detection of such compounds, it is important that forensic toxicology laboratories maintain up-to-date compound libraries for drug screening methods and that sensitive analytical instrumentation is available to detect the low blood\/plasma concentrations of more potent drugs. This includes not only the compounds themselves but also potential metabolites and\/or degradation products. Metonitazene is a \u2018nitro-nitazene\u2019 with a nitro group at position 5 of the benzimidazole ring. As a nitro-nitazene, there is a potential for bacterial degradation of metonitazene to 5-aminometonitazene, as occurs with nitro-benzodiazepines. In this study, we provide evidence from a postmortem (PM) case of degradation of metonitazene in unpreserved PM blood using liquid chromatography\u2013triple quadrupole mass spectrometry (LC\u2013QQQ-MS), and putative identification of the degradation\/metabolic products 5-aminometonitazene and 5-acetamidometonitazene by liquid chromatography\u2013quadrupole time-of-flight mass spectrometry. The results from LC\u2013QQQ-MS analysis indicated that there did not appear to be such degradation in preserved (fluoride\/oxalate) blood. These results suggest that nitro-nitazenes may be subject to similar in vitro stability\/degradation issues as nitro-benzodiazepines. These breakdown products should be added to instrument libraries to aid in the detection of the use of nitro-nitazenes, and nitro-nitazenes should be quantified in preserved blood samples where available.<\/jats:p>","DOI":"10.1093\/jat\/bkae076","type":"journal-article","created":{"date-parts":[[2024,9,2]],"date-time":"2024-09-02T12:34:43Z","timestamp":1725280483000},"page":"691-700","source":"Crossref","is-referenced-by-count":21,"title":["Identification of 5-aminometonitazene and 5-acetamidometonitazene in a postmortem case: are nitro-nitazenes unstable?"],"prefix":"10.1093","volume":"48","author":[{"ORCID":"https:\/\/orcid.org\/0009-0000-1413-143X","authenticated-orcid":false,"given":"Claire","family":"Parks","sequence":"first","affiliation":[{"name":"SPA Forensic Services , Govan, Glasgow G51 3AD,","place":["United Kingdom"]},{"name":"School of Medicine, Dentistry & Nursing, University of Glasgow , Glasgow G12 8QQ,","place":["United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3801-9658","authenticated-orcid":false,"given":"Peter D","family":"Maskell","sequence":"additional","affiliation":[{"name":"SPA Forensic Services , Govan, Glasgow G51 3AD,","place":["United Kingdom"]},{"name":"School of Medicine, Dentistry & Nursing, University of Glasgow , Glasgow G12 8QQ,","place":["United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Denise A","family":"McKeown","sequence":"additional","affiliation":[{"name":"SPA Forensic Services , Govan, Glasgow G51 3AD,","place":["United Kingdom"]},{"name":"School of Medicine, Dentistry & Nursing, University of Glasgow , Glasgow G12 8QQ,","place":["United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0464-7886","authenticated-orcid":false,"given":"Lewis","family":"Couchman","sequence":"additional","affiliation":[{"name":"Analytical Services International, St George\u2019s University of London , London SW17 0RE,","place":["United Kingdom"]},{"name":"Department of Analytical, Environmental and Forensic Sciences, King\u2019s College London , London SE1 9NH,","place":["United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2024,9,2]]},"reference":[{"key":"2024111514364448800_R1","article-title":"United States Patent Office Claims Priority, Application Switzerland","author":"Karl Hoffmann","year":"1956"},{"key":"2024111514364448800_R2","doi-asserted-by":"publisher","DOI":"10.7759\/cureus.40736","article-title":"Old drugs and new challenges: a narrative review of nitazenes","volume":"15","author":"Pergolizzi","year":"2023","journal-title":"Cureus"},{"key":"2024111514364448800_R3","doi-asserted-by":"publisher","first-page":"422","DOI":"10.1002\/dta.2738","article-title":"Report on a novel emerging class of highly potent benzimidazole NPS opioids: chemical and in 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