{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,4]],"date-time":"2026-07-04T00:23:22Z","timestamp":1783124602055,"version":"3.54.6"},"reference-count":25,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2017,11,15]],"date-time":"2017-11-15T00:00:00Z","timestamp":1510704000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Azathioprine is the main thiopurine drug used in the treatment of immune-based inflammations of gastrointestinal tract. For the purpose of therapy control and optimization, effective and reliable analytical methods for a rapid drug monitoring in biological fluids are essential. Here, we developed a separation method based on the capillary electrophoresis (CE) hyphenated with tandem mass spectrometry (MS\/MS) for the simultaneous determination of azathioprine and its selected metabolites (6-thioguanine, 6-mercaptopurine, and 6-methylmercaptopurine) as well as other co-medicated drugs (mesalazine, prednisone, and allopurinol). The optimized CE-MS\/MS conditions provided a very efficient and stable system for the separation and sensitive detection of these drugs in human urine matrices. The developed method was successfully applied for the assay of the targeted drugs and their selected metabolites in urine samples collected from patients suffering from inflammatory bowel disease (IBD) and receiving azathioprine therapy. The developed CE-MS\/MS method, due to its reliability, short analysis time, production of complex clinical profiles, and favorable performance parameters, evaluated according to FDA guidelines for bioanalytical method validation, is proposed for routine clinical laboratories to optimize thiopurine therapy, estimate enzymatic activity, and control patient compliance with medication and co-medication.<\/jats:p>","DOI":"10.3390\/molecules22111973","type":"journal-article","created":{"date-parts":[[2017,11,15]],"date-time":"2017-11-15T11:13:35Z","timestamp":1510744415000},"page":"1973","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Capillary Electrophoresis Hyphenated with Mass Spectrometry for Determination of Inflammatory Bowel Disease Drugs in Clinical Urine Samples"],"prefix":"10.3390","volume":"22","author":[{"given":"Katar\u00edna","family":"Mar\u00e1kov\u00e1","sequence":"first","affiliation":[{"name":"Department of Pharmaceutical Analysis and Nuclear Pharmacy, Faculty of Pharmacy, Comenius University in Bratislava, Odboj\u00e1rov 10, SK-832 32 Bratislava, Slovakia"},{"name":"Toxicological and Antidoping Center (TAC), Faculty of Pharmacy, Comenius University in Bratislava, Odboj\u00e1rov 10, SK-832 32 Bratislava, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juraj","family":"Pie\u0161\u0165ansk\u00fd","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Analysis and Nuclear Pharmacy, Faculty of Pharmacy, Comenius University in Bratislava, Odboj\u00e1rov 10, SK-832 32 Bratislava, Slovakia"},{"name":"Toxicological and Antidoping Center (TAC), Faculty of Pharmacy, Comenius University in Bratislava, Odboj\u00e1rov 10, SK-832 32 Bratislava, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zuzana","family":"Zelinkov\u00e1","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, St Michael\u2019s Hospital, Satinsk\u00e9ho 1, SK-811 08 Bratislava, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peter","family":"Miku\u0161","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Analysis and Nuclear Pharmacy, Faculty of Pharmacy, Comenius University in Bratislava, Odboj\u00e1rov 10, SK-832 32 Bratislava, Slovakia"},{"name":"Toxicological and Antidoping Center (TAC), Faculty of Pharmacy, Comenius University in Bratislava, Odboj\u00e1rov 10, SK-832 32 Bratislava, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,11,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"46","DOI":"10.1053\/j.gastro.2011.10.001","article-title":"Increasing incidence and prevalence of the inflammatory bowel diseases with time, based on systematic review","volume":"142","author":"Molodecky","year":"2012","journal-title":"Gastroenterology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1699","DOI":"10.3748\/wjg.v19.i11.1699","article-title":"Thiopurines in inflammatory bowel disease revisited","volume":"19","author":"Sina","year":"2013","journal-title":"World J. 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