{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T13:07:32Z","timestamp":1781183252171,"version":"3.54.1"},"reference-count":24,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2024,10,18]],"date-time":"2024-10-18T00:00:00Z","timestamp":1729209600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union and the Ministry of Hungary","award":["GINOP-2.3.3-15-2016-00020"],"award-info":[{"award-number":["GINOP-2.3.3-15-2016-00020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Autoimmune hepatitis (AIH) is a chronic inflammatory liver disease treated by steroids and immunomodulator thiopurine drugs such as azathioprine (AZA). AZA is metabolized in the human body into bioactive forms such as 6-thioguanine (6-TG) and 6-methyl-mercaptopurine (6-MMP). Monitoring the levels of bioactive AZA metabolites is very important for proper treatment of patients. In this study, our aim was to develop and validate a fast and sensitive ultra-high performance liquid chromatography\u2013mass spectrometry (UHPLC\u2013MS) method for the analysis of 6-TG and 6-MMP from blood samples of patients with AIH to monitor the level of these bioactive metabolites. The detection and quantification of the analytes was carried out by Selected Reaction Monitoring (SRM)-based targeted mass spectrometry. The method was validated according to the EMA guidelines. Blood samples from patients with AIH treated with AZA were analysed with the developed method. The method was successfully validated with appropriate accuracy and precision for the target biomolecules and their concentration in the samples from patients with AIH was determined. The developed and validated UHPLC\u2013MS method enables the fast and precise analysis of AZA metabolites.<\/jats:p>","DOI":"10.3390\/ijms252011233","type":"journal-article","created":{"date-parts":[[2024,10,21]],"date-time":"2024-10-21T03:57:09Z","timestamp":1729483029000},"page":"11233","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Analysis of Azathioprine Metabolites in Autoimmune Hepatitis Patient Blood\u2014Method Development and Validation"],"prefix":"10.3390","volume":"25","author":[{"given":"Andrea","family":"Guba","sequence":"first","affiliation":[{"name":"Proteomics Core Facility, Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Egyetem t\u00e9r 1, 4032 Debrecen, Hungary"},{"name":"Metabolomics Research Group, Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Egyetem t\u00e9r 1, 4032 Debrecen, Hungary"},{"name":"Doctoral School of Molecular Cell and Immune Biology, University of Debrecen, Egyetem t\u00e9r 1, 4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Patr\u00edcia","family":"Kov\u00e1ts","sequence":"additional","affiliation":[{"name":"Division of Gastroenterology, Department of Internal Medicine, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98, 4032 Debrecen, Hungary"},{"name":"K\u00e1lm\u00e1n Laki Doctoral School, University of Debrecen, Egyetem t\u00e9r 1, 4032 Debrecen, Hungary"},{"name":"Institute of Gastroenterology, European Reference Network on Hepatological Diseases, ERN RARE-LIVER, Clinical Center, 4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7886-8665","authenticated-orcid":false,"given":"Zolt\u00e1n A.","family":"Mezei","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98, 4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3662-4010","authenticated-orcid":false,"given":"M\u00e1ria","family":"Papp","sequence":"additional","affiliation":[{"name":"Division of Gastroenterology, Department of Internal Medicine, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98, 4032 Debrecen, Hungary"},{"name":"K\u00e1lm\u00e1n Laki Doctoral School, University of Debrecen, Egyetem t\u00e9r 1, 4032 Debrecen, Hungary"},{"name":"Institute of Gastroenterology, European Reference Network on Hepatological Diseases, ERN RARE-LIVER, Clinical Center, 4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4373-2175","authenticated-orcid":false,"given":"\u00c9va","family":"Cs\u0151sz","sequence":"additional","affiliation":[{"name":"Proteomics Core Facility, Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Egyetem t\u00e9r 1, 4032 Debrecen, Hungary"},{"name":"Metabolomics Research Group, Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Egyetem t\u00e9r 1, 4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5732-8758","authenticated-orcid":false,"given":"Gerg\u0151","family":"Kall\u00f3","sequence":"additional","affiliation":[{"name":"Proteomics Core Facility, Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Egyetem t\u00e9r 1, 4032 Debrecen, Hungary"},{"name":"Metabolomics Research Group, Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Egyetem t\u00e9r 1, 4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1156","DOI":"10.1177\/2050640619872408","article-title":"Clinical management of autoimmune hepatitis","volume":"7","author":"Pape","year":"2019","journal-title":"United Eur. 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