{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T07:41:33Z","timestamp":1773819693017,"version":"3.50.1"},"reference-count":38,"publisher":"Springer Science and Business Media LLC","issue":"7","license":[{"start":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T00:00:00Z","timestamp":1769558400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T00:00:00Z","timestamp":1769558400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/100007691","name":"Universidade da Beira Interior","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100007691","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Anal Bioanal Chem"],"published-print":{"date-parts":[[2026,4]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>The opioid crisis remains a significant public health concern, necessitating the development of sensitive and reliable analytical methods for drug detection. This study aimed to develop and validate a liquid chromatography\u2013tandem mass spectrometry (LC\u2013MS\/MS) method for the simultaneous detection and quantification of fentanyl, buprenorphine, oxycodone, morphine, tramadol, and tapentadol in plasma and oral fluid. The method was validated according to FDA guidelines, assessing selectivity, linearity, precision, accuracy, matrix effect, extraction efficiency, stability, carryover, and dilution integrity. The lower limits of quantification (LLOQs) were established at 0.1\u00a0ng\/mL for fentanyl, 1.2\u00a0ng\/mL for tramadol, and 0.6\u00a0ng\/mL for the remaining opioids, demonstrating high sensitivity. The method exhibited excellent precision and accuracy, with coefficients of variation below 15% for intra-day, inter-day, and intermediate precision analyses. Extraction efficiencies exceeded 90% for most analytes, and matrix effects remained within acceptable limits. Real-world application to authentic plasma and oral fluid samples confirmed the method\u2019s robustness and reliability. Oral fluid concentrations were detectable across all target opioids, although plasma\u2013oral fluid ratios showed some compound-dependent variability. These findings highlight the potential of oral fluid as a non-invasive complementary matrix to plasma for opioid monitoring, with relevant implications for forensic toxicology and clinical drug monitoring.<\/jats:p>\n                  <jats:p>\n                    <jats:bold>Graphical Abstract<\/jats:bold>\n                  <\/jats:p>","DOI":"10.1007\/s00216-026-06336-1","type":"journal-article","created":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T01:23:01Z","timestamp":1769563381000},"page":"2107-2123","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Opioid detection and quantification in plasma and oral fluid by LC\u2013MS\/MS"],"prefix":"10.1007","volume":"418","author":[{"given":"Luana M.","family":"Rosendo","sequence":"first","affiliation":[]},{"given":"Suzel","family":"Costa","sequence":"additional","affiliation":[]},{"given":"Susana","family":"Sim\u00f5es","sequence":"additional","affiliation":[]},{"given":"Jo\u00e3o M.","family":"Franco","sequence":"additional","affiliation":[]},{"given":"Noelia","family":"Serrano Gadea","sequence":"additional","affiliation":[]},{"given":"M\u00f3nica","family":"Escorial","sequence":"additional","affiliation":[]},{"given":"Francisco Javier","family":"Toboso Ortega","sequence":"additional","affiliation":[]},{"given":"Segundo","family":"Jim\u00e9nez-Garc\u00eda","sequence":"additional","affiliation":[]},{"given":"Ana M.","family":"Peir\u00f3","sequence":"additional","affiliation":[]},{"given":"Isabel","family":"Duque","sequence":"additional","affiliation":[]},{"given":"Tiago","family":"Rosado","sequence":"additional","affiliation":[]},{"given":"M\u00e1rio","family":"Barroso","sequence":"additional","affiliation":[]},{"given":"Eugenia","family":"Gallardo","sequence":"additional","affiliation":[]}],"member":"297","published-online":{"date-parts":[[2026,1,28]]},"reference":[{"key":"6336_CR1","doi-asserted-by":"publisher","first-page":"290","DOI":"10.15585\/mmwr.mm6911a4","volume":"69","author":"N Wilson","year":"2020","unstructured":"Wilson N, Kariisa M, Seth P, Smith H, Davis NL. Drug and opioid-involved overdose deaths \u2014 United States, 2017\u20132018. MMWR Morb Mortal Wkly Rep. 2020;69:290\u20137. https:\/\/doi.org\/10.15585\/mmwr.mm6911a4.","journal-title":"MMWR Morb Mortal Wkly Rep"},{"key":"6336_CR2","doi-asserted-by":"crossref","unstructured":"Polston G. Opioid overdose. In: Challenging cases and complication management in pain medicine. Cham: Springer International Publishing; 2018. pp. 3\u20137.","DOI":"10.1007\/978-3-319-60072-7_1"},{"key":"6336_CR3","doi-asserted-by":"publisher","first-page":"121","DOI":"10.1016\/j.neuropharm.2017.10.016","volume":"134","author":"P Armenian","year":"2018","unstructured":"Armenian P, Vo KT, Barr-Walker J, Lynch KL. Fentanyl, fentanyl analogs and novel synthetic opioids: a comprehensive review. Neuropharmacology. 2018;134:121\u201332. https:\/\/doi.org\/10.1016\/j.neuropharm.2017.10.016.","journal-title":"Neuropharmacology"},{"key":"6336_CR4","doi-asserted-by":"publisher","first-page":"1560","DOI":"10.1016\/S0140-6736(19)32229-9","volume":"394","author":"L Degenhardt","year":"2019","unstructured":"Degenhardt L, Grebely J, Stone J, Hickman M, Vickerman P, Marshall BDL, et al. Global patterns of opioid use and dependence: harms to populations, interventions, and future action. Lancet. 2019;394:1560\u201379. https:\/\/doi.org\/10.1016\/S0140-6736(19)32229-9.","journal-title":"Lancet"},{"key":"6336_CR5","doi-asserted-by":"publisher","first-page":"108019","DOI":"10.1016\/j.pharmthera.2021.108019","volume":"233","author":"P Skolnick","year":"2022","unstructured":"Skolnick P. Treatment of overdose in the synthetic opioid era. Pharmacol Ther. 2022;233:108019. https:\/\/doi.org\/10.1016\/j.pharmthera.2021.108019.","journal-title":"Pharmacol Ther"},{"key":"6336_CR6","doi-asserted-by":"publisher","first-page":"1730","DOI":"10.1136\/bmj.p1730","volume":"382","author":"E Mahase","year":"2023","unstructured":"Mahase E. Potent synthetic opioids are linked to rise in heroin overdoses and deaths in England. BMJ. 2023;382:1730. https:\/\/doi.org\/10.1136\/bmj.p1730.","journal-title":"BMJ"},{"key":"6336_CR7","unstructured":"GOV.UK. Deaths linked to potent synthetic opioids. 2025. https:\/\/www.gov.uk\/government\/publications\/deaths-linked-to-potent-synthetic-opioids\/deaths-linked-to-potent-synthetic-opioids. Accessed 4 Feb 2025."},{"key":"6336_CR8","doi-asserted-by":"publisher","first-page":"42","DOI":"10.1097\/FTD.0000000000000789","volume":"43","author":"J Van Amsterdam","year":"2021","unstructured":"Van Amsterdam J, Pierce M, van den Brink W. Is Europe facing an emerging opioid crisis comparable to the U.S.? Ther Drug Monit. 2021;43:42\u201351. https:\/\/doi.org\/10.1097\/FTD.0000000000000789.","journal-title":"Ther Drug Monit"},{"key":"6336_CR9","doi-asserted-by":"publisher","first-page":"1760","DOI":"10.1002\/ejp.1786","volume":"25","author":"W H\u00e4user","year":"2021","unstructured":"H\u00e4user W, Buchser E, Finn DP, Dom G, Fors E, Heiskanen T, et al. Is Europe also facing an opioid crisis?\u2014A survey of European Pain Federation chapters. Eur J Pain. 2021;25:1760\u20139. https:\/\/doi.org\/10.1002\/ejp.1786.","journal-title":"Eur J Pain"},{"key":"6336_CR10","doi-asserted-by":"publisher","first-page":"461241","DOI":"10.1016\/j.chroma.2020.461241","volume":"1624","author":"KF da Cunha","year":"2020","unstructured":"da Cunha KF, Rodrigues LC, Huestis MA, Costa JL. Miniaturized extraction method for analysis of synthetic opioids in urine by microextraction with packed sorbent and liquid chromatography\u2013tandem mass spectrometry. J Chromatogr A. 2020;1624:461241. https:\/\/doi.org\/10.1016\/j.chroma.2020.461241.","journal-title":"J Chromatogr A"},{"key":"6336_CR11","doi-asserted-by":"publisher","first-page":"641","DOI":"10.3390\/molecules27030641","volume":"27","author":"E Almeida","year":"2022","unstructured":"Almeida E, Soares S, Gon\u00e7alves J, Rosado T, Fern\u00e1ndez N, Rodilla JM, et al. Stability of cocaine, opiates, and metabolites in dried saliva spots. Molecules. 2022;27:641. https:\/\/doi.org\/10.3390\/molecules27030641.","journal-title":"Molecules"},{"key":"6336_CR12","doi-asserted-by":"publisher","first-page":"465","DOI":"10.1093\/jat\/bkz029","volume":"43","author":"T Rosado","year":"2019","unstructured":"Rosado T, Barroso M, Vieira DN, Gallardo E. Determination of selected opiates in hair samples using microextraction by packed sorbent: a new approach for sample clean-up. J Anal Toxicol. 2019;43:465\u201376. https:\/\/doi.org\/10.1093\/jat\/bkz029.","journal-title":"J Anal Toxicol"},{"key":"6336_CR13","doi-asserted-by":"publisher","first-page":"6761","DOI":"10.3390\/molecules27196761","volume":"27","author":"S Yasien","year":"2022","unstructured":"Yasien S, Ali E, Javed M, Iqbal MM, Iqbal S, Alrbyawi H, et al. Simultaneous quantification of opioids in blood and urine by gas chromatography\u2013mass spectrometer with modified dispersive solid-phase extraction technique. Molecules. 2022;27:6761. https:\/\/doi.org\/10.3390\/molecules27196761.","journal-title":"Molecules"},{"key":"6336_CR14","doi-asserted-by":"publisher","first-page":"1962","DOI":"10.3390\/biomedicines11071962","volume":"11","author":"A Cafaro","year":"2023","unstructured":"Cafaro A, Conti M, Pigliasco F, Barco S, Bandettini R, Cangemi G. Biological fluid microsampling for therapeutic drug monitoring: a narrative review. Biomedicines. 2023;11:1962. https:\/\/doi.org\/10.3390\/biomedicines11071962.","journal-title":"Biomedicines"},{"key":"6336_CR15","doi-asserted-by":"publisher","first-page":"657","DOI":"10.4155\/bio-2023-0122","volume":"15","author":"E Gallardo","year":"2023","unstructured":"Gallardo E, Rosado T, Barroso M. The potential of oral fluid in drug monitoring: an update. Bioanalysis. 2023;15:657\u201360. https:\/\/doi.org\/10.4155\/bio-2023-0122.","journal-title":"Bioanalysis"},{"key":"6336_CR16","doi-asserted-by":"publisher","first-page":"415","DOI":"10.1093\/jat\/bkz048","volume":"43","author":"NA Desrosiers","year":"2019","unstructured":"Desrosiers NA, Huestis MA. Oral fluid drug testing: analytical approaches, issues and interpretation of results. J Anal Toxicol. 2019;43:415\u201343. https:\/\/doi.org\/10.1093\/jat\/bkz048.","journal-title":"J Anal Toxicol"},{"key":"6336_CR17","doi-asserted-by":"publisher","first-page":"51","DOI":"10.1196\/annals.1391.043","volume":"1098","author":"EJ Cone","year":"2007","unstructured":"Cone EJ, Huestis MA. Interpretation of oral fluid tests for drugs of abuse. Ann N Y Acad Sci. 2007;1098:51\u2013103. https:\/\/doi.org\/10.1196\/annals.1391.043.","journal-title":"Ann N Y Acad Sci"},{"key":"6336_CR18","unstructured":"Rosado T, Soares S, Malaca S, Gon\u00e7alves J, Barroso M, Gallardo E. The role of liquid chromatography in toxicological analysis. In: High-performance liquid chromatography: types, parameters and applications. 2018. pp. 1\u2013120."},{"key":"6336_CR19","unstructured":"Food and Drug Administration. Bioanalytical method validation guidance for industry. 2018."},{"key":"6336_CR20","unstructured":"U.S. Department of Health and Human Services. Mandatory guidelines for federal workplace drug testing programs. Federal Register. 2025. https:\/\/www.federalregister.gov\/documents\/2025\/01\/16\/2025-00425\/mandatory-guidelines-for-federal-workplace-drug-testing-programs-authorized-testing-panels. Accessed 17 Feb 2025."},{"key":"6336_CR21","doi-asserted-by":"publisher","first-page":"269","DOI":"10.1002\/dta.284","volume":"3","author":"G Cooper","year":"2011","unstructured":"Cooper G, Moore C, George C, Pichini S. Guidelines for European workplace drug testing in oral fluid. Drug Test Anal. 2011;3:269\u201376. https:\/\/doi.org\/10.1002\/dta.284.","journal-title":"Drug Test Anal"},{"key":"6336_CR22","doi-asserted-by":"publisher","first-page":"899","DOI":"10.1093\/jat\/bkac031","volume":"46","author":"C Coulter","year":"2022","unstructured":"Coulter C, Garnier M, Moore C. Rapid extraction and qualitative screening of 30 drugs in oral fluid at concentrations recommended for the investigation of DUID cases. J Anal Toxicol. 2022;46:899\u2013904. https:\/\/doi.org\/10.1093\/jat\/bkac031.","journal-title":"J Anal Toxicol"},{"key":"6336_CR23","doi-asserted-by":"publisher","first-page":"3647","DOI":"10.1007\/s00216-015-8583-8","volume":"407","author":"C Montesano","year":"2015","unstructured":"Montesano C, Simeoni MC, Curini R, Sergi M, Lo Sterzo C, Compagnone D. Determination of illicit drugs and metabolites in oral fluid by microextraction on packed sorbent coupled with LC-MS\/MS. Anal Bioanal Chem. 2015;407:3647\u201358. https:\/\/doi.org\/10.1007\/s00216-015-8583-8.","journal-title":"Anal Bioanal Chem"},{"key":"6336_CR24","doi-asserted-by":"publisher","first-page":"554","DOI":"10.1093\/jat\/bky053","volume":"42","author":"MT Truver","year":"2018","unstructured":"Truver MT, Swortwood MJ. Quantitative analysis of novel synthetic opioids, morphine and buprenorphine in oral fluid by LC-MS\/MS. J Anal Toxicol. 2018;42:554\u201361. https:\/\/doi.org\/10.1093\/jat\/bky053.","journal-title":"J Anal Toxicol"},{"key":"6336_CR25","doi-asserted-by":"publisher","first-page":"392","DOI":"10.1093\/jat\/bky021","volume":"42","author":"M Grabenauer","year":"2018","unstructured":"Grabenauer M, Moore KN, Bynum ND, White RM, Mitchell JM, Hayes ED, et al. Development of a quantitative LC-MS\/MS assay for codeine, morphine, 6-acetylmorphine, hydrocodone, hydromorphone, oxycodone and oxymorphone in neat oral fluid. J Anal Toxicol. 2018;42:392\u20139. https:\/\/doi.org\/10.1093\/jat\/bky021.","journal-title":"J Anal Toxicol"},{"key":"6336_CR26","doi-asserted-by":"publisher","first-page":"454","DOI":"10.1016\/j.talanta.2017.06.022","volume":"174","author":"AM Ares","year":"2017","unstructured":"Ares AM, Fern\u00e1ndez P, Regenjo M, Fern\u00e1ndez AM, Carro AM, Lorenzo RA. A fast bioanalytical method based on microextraction by packed sorbent and UPLC\u2013MS\/MS for determining new psychoactive substances in oral fluid. Talanta. 2017;174:454\u201361. https:\/\/doi.org\/10.1016\/j.talanta.2017.06.022.","journal-title":"Talanta"},{"key":"6336_CR27","doi-asserted-by":"publisher","first-page":"27","DOI":"10.1016\/j.jchromb.2014.04.019","volume":"960","author":"SR Bista","year":"2014","unstructured":"Bista SR, Lobb M, Haywood A, Hardy J, Tapuni A, Norris R. Development, validation and application of an HPLC-MS\/MS method for the determination of fentanyl and norfentanyl in human plasma and saliva. J Chromatogr B. 2014;960:27\u201333. https:\/\/doi.org\/10.1016\/j.jchromb.2014.04.019.","journal-title":"J Chromatogr B"},{"key":"6336_CR28","doi-asserted-by":"publisher","first-page":"114171","DOI":"10.1016\/j.jpba.2021.114171","volume":"203","author":"AA Al-Qurain","year":"2021","unstructured":"Al-Qurain AA, Williams DB, Mackenzie L, Roberts MS, Wiese MD. Simultaneous LC-MS\/MS quantification of oxycodone, tramadol and fentanyl and their metabolites in human plasma and whole blood collected via venepuncture and volumetric absorptive microsampling. J Pharm Biomed Anal. 2021;203:114171. https:\/\/doi.org\/10.1016\/j.jpba.2021.114171.","journal-title":"J Pharm Biomed Anal"},{"key":"6336_CR29","doi-asserted-by":"publisher","first-page":"335","DOI":"10.3390\/molecules29020335","volume":"29","author":"K Gory\u0144ski","year":"2024","unstructured":"Gory\u0144ski K, Sobczak \u0141, Ko\u0142odziej D. Developing and evaluating the greenness of a reliable, all-in-one thin-film microextraction protocol for determining fentanyl, methadone, and zolpidem in plasma, urine, and oral fluid. Molecules. 2024;29:335. https:\/\/doi.org\/10.3390\/molecules29020335.","journal-title":"Molecules"},{"key":"6336_CR30","doi-asserted-by":"publisher","first-page":"633","DOI":"10.1002\/jms.1021","volume":"41","author":"F Musshoff","year":"2006","unstructured":"Musshoff F, Trafkowski J, Kuepper U, Madea B. An automated and fully validated LC-MS\/MS procedure for the simultaneous determination of 11 opioids used in palliative care, with 5 of their metabolites. J Mass Spectrom. 2006;41:633\u201340. https:\/\/doi.org\/10.1002\/jms.1021.","journal-title":"J Mass Spectrom"},{"key":"6336_CR31","doi-asserted-by":"publisher","first-page":"299","DOI":"10.1002\/npr2.12268","volume":"42","author":"S Ito","year":"2022","unstructured":"Ito S, Mori M, Matsuo M, Yamasaki R, Oida Y, Soda M, et al. Establishment to measure oxycodone in plasma with liquid chromatography\u2013tandem mass spectrometry. Neuropsychopharmacol Rep. 2022;42:299\u2013305. https:\/\/doi.org\/10.1002\/npr2.12268.","journal-title":"Neuropsychopharmacol Rep"},{"key":"6336_CR32","doi-asserted-by":"publisher","first-page":"354","DOI":"10.1016\/j.jpba.2008.10.030","volume":"49","author":"BN Patel","year":"2009","unstructured":"Patel BN, Sharma N, Sanyal M, Shrivastav PS. An accurate, rapid and sensitive determination of tramadol and its active metabolite O-desmethyltramadol in human plasma by LC-MS\/MS. J Pharm Biomed Anal. 2009;49:354\u201366. https:\/\/doi.org\/10.1016\/j.jpba.2008.10.030.","journal-title":"J Pharm Biomed Anal"},{"key":"6336_CR33","doi-asserted-by":"publisher","first-page":"715","DOI":"10.1007\/s00216-011-4775-z","volume":"400","author":"CF Clavijo","year":"2011","unstructured":"Clavijo CF, Hoffman KL, Thomas JJ, Carvalho B, Chu LF, Drover DR, et al. A sensitive assay for the quantification of morphine and its active metabolites in human plasma and dried blood spots using high-performance liquid chromatography\u2013tandem mass spectrometry. Anal Bioanal Chem. 2011;400:715\u201328. https:\/\/doi.org\/10.1007\/s00216-011-4775-z.","journal-title":"Anal Bioanal Chem"},{"key":"6336_CR34","doi-asserted-by":"publisher","first-page":"124104","DOI":"10.1016\/j.jchromb.2024.124104","volume":"1237","author":"J Thomann","year":"2024","unstructured":"Thomann J, Vogt SB, Guessoum A, Meyer M, Vogel M, Liechti ME, et al. Development and validation of an LC-MS\/MS method for quantifying diamorphine and its major metabolites 6-monoacetylmorphine, morphine, morphine-3-glucuronide, and morphine-6-glucuronide in human plasma. J Chromatogr B. 2024;1237:124104. https:\/\/doi.org\/10.1016\/j.jchromb.2024.124104.","journal-title":"J Chromatogr B"},{"key":"6336_CR35","doi-asserted-by":"publisher","first-page":"e5015","DOI":"10.1002\/jms.5015","volume":"59","author":"W Zhao","year":"2024","unstructured":"Zhao W, Alshogran OY, Zhang H, Joshi A, Krans EE, Caritis S, et al. Simplified processing and rapid quantification of buprenorphine, norbuprenorphine, and their conjugated metabolites in human plasma using UPLC\u2013MS\/MS: assessment of buprenorphine exposure during opioid use disorder treatment. J Mass Spectrom. 2024;59:e5015. https:\/\/doi.org\/10.1002\/jms.5015.","journal-title":"J Mass Spectrom"},{"key":"6336_CR36","doi-asserted-by":"publisher","first-page":"70","DOI":"10.1016\/j.chroma.2016.03.076","volume":"1446","author":"MJ Swortwood","year":"2016","unstructured":"Swortwood MJ, Scheidweiler KB, Barnes AJ, Jansson LM, Huestis MA. Simultaneous quantification of buprenorphine, naloxone and phase I and II metabolites in plasma and breastmilk by liquid chromatography\u2013tandem mass spectrometry. J Chromatogr A. 2016;1446:70\u20137. https:\/\/doi.org\/10.1016\/j.chroma.2016.03.076.","journal-title":"J Chromatogr A"},{"key":"6336_CR37","doi-asserted-by":"publisher","first-page":"637","DOI":"10.1016\/j.jchromb.2010.01.014","volume":"878","author":"M Wagner","year":"2010","unstructured":"Wagner M, Bourgogne E, Varesio E, Hopfgartner G. Quantitation of polar analytes using column-switching: application to oxycodone and three metabolites in human plasma. J Chromatogr B. 2010;878:637\u201344. https:\/\/doi.org\/10.1016\/j.jchromb.2010.01.014.","journal-title":"J Chromatogr B"},{"key":"6336_CR38","doi-asserted-by":"publisher","first-page":"915","DOI":"10.1007\/s00216-010-3903-5","volume":"398","author":"M Concheiro","year":"2010","unstructured":"Concheiro M, Gray TR, Shakleya DM, Huestis MA. High-throughput simultaneous analysis of buprenorphine, methadone, cocaine, opiates, nicotine, and metabolites in oral fluid by liquid chromatography\u2013tandem mass spectrometry. Anal Bioanal Chem. 2010;398:915\u201324. https:\/\/doi.org\/10.1007\/s00216-010-3903-5.","journal-title":"Anal Bioanal Chem"}],"container-title":["Analytical and Bioanalytical Chemistry"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s00216-026-06336-1.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s00216-026-06336-1","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s00216-026-06336-1.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T06:36:31Z","timestamp":1773815791000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1007\/s00216-026-06336-1"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,28]]},"references-count":38,"journal-issue":{"issue":"7","published-print":{"date-parts":[[2026,4]]}},"alternative-id":["6336"],"URL":"https:\/\/doi.org\/10.1007\/s00216-026-06336-1","relation":{},"ISSN":["1618-2642","1618-2650"],"issn-type":[{"value":"1618-2642","type":"print"},{"value":"1618-2650","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,28]]},"assertion":[{"value":"15 October 2025","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"14 December 2025","order":2,"name":"revised","label":"Revised","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"7 January 2026","order":3,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"28 January 2026","order":4,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"The study was conducted by the Declaration of Helsinki. The project \u201cOpioid Monitoring and Assessment of CYP2D6, OPRM1, and COMT Phenotypes in Pain Management: Towards a Personalized Therapy\u201d received approval from the Ethics Committees of ULSCB, EPE and ISABIAL.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval"}},{"value":"The authors declare no competing interests.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of interest"}}]}}