{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,21]],"date-time":"2026-06-21T05:48:48Z","timestamp":1782020928808,"version":"3.54.5"},"reference-count":27,"publisher":"Springer Science and Business Media LLC","license":[{"start":{"date-parts":[[2026,6,21]],"date-time":"2026-06-21T00:00:00Z","timestamp":1782000000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,6,21]],"date-time":"2026-06-21T00:00:00Z","timestamp":1782000000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/100007684","name":"Asahi Glass Foundation","doi-asserted-by":"publisher","award":["Asahi Glass Foundation"],"award-info":[{"award-number":["Asahi Glass Foundation"]}],"id":[{"id":"10.13039\/100007684","id-type":"DOI","asserted-by":"publisher"}]},{"name":"JSPS KAKENHI","award":["25K02898"],"award-info":[{"award-number":["25K02898"]}]},{"name":"JSPS KAKENHI","award":["24K21304"],"award-info":[{"award-number":["24K21304"]}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Forensic Toxicol"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>Flunitrazepam is a widely used hypnotic agent detected in many fatal intoxication and suicide cases. However, its concentration in blood during autopsy differs from that at the time of death; it is either undetected or detected at lower concentrations than expected in post-mortem blood. In this study, we evaluated interactions between flunitrazepam and human blood using liquid chromatography coupled with quadrupole-Orbitrap mass spectrometry (LC-Q-Orbitrap-MS).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We measured flunitrazepam, 7-aminoflunitrazepam via reduction by aldehyde oxidase 1 (AOX1), and the degradation product of 7-aminoflunitrazepam via the Fenton reaction by hemoglobin (Hb) in human blood. In addition, we also detected flunitrazepam, 7-aminoflunitrazepam, and their degradation products in the blood of individuals who died from intentional ingestion of flunitrazepam.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      We found that flunitrazepam was reduced to 7-aminoflunitrazepam by AOX1 in blood, and 7-aminoflunitrazepam was oxidized by Hb via the Fenton reaction. The mass spectra obtained by LC-Q-Orbitrap-MS revealed the formation of 7-amino-5-(2-fluorocyclohexa-1,3-dien-1-yl)-3-hydroxy-1-methyl-1,3-dihydro-2\n                      <jats:italic>H<\/jats:italic>\n                      -benzo[e][1,4]diazepin-2-one (7-amino-3-hydroxyflunitrazepam) in the Hb\/H\n                      <jats:sub>2<\/jats:sub>\n                      O\n                      <jats:sub>2<\/jats:sub>\n                      reaction mixture containing 7-aminoflunitrazepam, as well as in the blood of some individuals who died from intentional ingestion of flunitrazepam.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>7-Amino-3-hydroxyflunitrazepam is the degradation product of flunitrazepam at various temperatures. The degradation is brought about by post-mortem changes via AOX1-mediated reduction and Hb-mediated Fenton reaction. Thus, 7-amino-3-hydroxyflunitrazepam may be a valuable biomarker for correcting blood flunitrazepam concentration at the time of death in clinical cases.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s11419-026-00777-0","type":"journal-article","created":{"date-parts":[[2026,6,21]],"date-time":"2026-06-21T05:37:29Z","timestamp":1782020249000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Post-mortem degradation of flunitrazepam by aldehyde oxidase 1 and hemoglobin in blood"],"prefix":"10.1007","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6719-5186","authenticated-orcid":false,"given":"Yoshikazu","family":"Yamagishi","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hiroyuki","family":"Inoue","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sayaka","family":"Nagasawa","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hirotaro","family":"Iwase","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yasumitsu","family":"Ogra","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,6,21]]},"reference":[{"key":"777_CR1","doi-asserted-by":"publisher","first-page":"25","DOI":"10.1007\/s11419-009-0088-8","volume":"28","author":"K Kudo","year":"2010","unstructured":"Kudo K, Ishida T, Hikiji W, Usumoto Y, Umehara T, Nagamatsu K, Tsuji A, Ikeda N (2010) Pattern of poisoning in Japan: selection of drugs and poisons for systematic toxicological analysis. 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R001, Graduate School of Pharmaceutical Sciences; approval no. 2819, Graduate School of Medicine). The use of autopsy samples for analysis conformed to the Code of Ethics of the World Medical Association (Declaration of Helsinki). At the request of investigation agencies, we conduct forensic autopsies as part of criminal investigations. We are not allowed to meet or contact the families before or after the autopsies. Therefore, we have included a disclaimer on our official website stating that we occasionally collect samples from autopsies for research purposes, and that if the families do not consent to the deceased\u2019s body being used for research, they can opt out and inform us by fax.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval"}}]}}