{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T08:30:33Z","timestamp":1777365033081,"version":"3.51.4"},"reference-count":51,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2021,11,10]],"date-time":"2021-11-10T00:00:00Z","timestamp":1636502400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Polish National Centre for Science","award":["2019\/33\/N\/NZ5\/02303"],"award-info":[{"award-number":["2019\/33\/N\/NZ5\/02303"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Iodine is an essential component for fetal neurodevelopment and maternal thyroid function. Urine iodine is the most widely used indicator of iodine status. In this study, a novel validated ion-pair HPLC\u2013UV method was developed to measure iodine concentration in clinical samples. A sodium thiosulfate solution was added to the urine sample to convert the total free iodine to iodide. Chromatographic separation was achieved in a Pursuit XRs C8 column. The mobile phase consisted of acetonitrile and a water phase containing 18-crown-6-ether, octylamine and sodium dihydrogen phosphate. Validation parameters, such as accuracy, precision, limits of detection and quantification, linearity and stability, were determined. Urinary samples from pregnant women were used to complete the validation and confirm the method\u2019s applicability. In the studied population of 93 pregnant women, the median UIC was lower in the group without iodine supplementation (117 \u00b5g\/L, confidence interval (%CI): 95; 138) than in the supplement group (133 \u00b5g\/L, %CI: 109; 157). In conclusion, the newly established ion-pair HPLC\u2013UV method was adequately precise, accurate and fulfilled validation the criteria for analyzing compounds in biological fluids. The method is less complicated and expensive than other frequently used assays and permits the identification of the iodine-deficient subjects.<\/jats:p>","DOI":"10.3390\/molecules26226797","type":"journal-article","created":{"date-parts":[[2021,11,11]],"date-time":"2021-11-11T23:04:46Z","timestamp":1636671886000},"page":"6797","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["HPLC Analysis of the Urinary Iodine Concentration in Pregnant Women"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3879-3267","authenticated-orcid":false,"given":"Aniceta A.","family":"Mikulska","sequence":"first","affiliation":[{"name":"Department of Physical Pharmacy and Pharmacokinetics, Poznan University of Medical Sciences, 60-781 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dorota","family":"Filipowicz","sequence":"additional","affiliation":[{"name":"Department of Endocrinology, Metabolism and Internal Medicine, Poznan University of Medical Sciences, 60-356 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6611-5789","authenticated-orcid":false,"given":"Franciszek K.","family":"G\u0142\u00f3wka","sequence":"additional","affiliation":[{"name":"Department of Physical Pharmacy and Pharmacokinetics, Poznan University of Medical Sciences, 60-781 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ewelina","family":"Szczepanek-Parulska","sequence":"additional","affiliation":[{"name":"Department of Endocrinology, Metabolism and Internal Medicine, Poznan University of Medical Sciences, 60-356 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6296-7220","authenticated-orcid":false,"given":"Marek","family":"Rucha\u0142a","sequence":"additional","affiliation":[{"name":"Department of Endocrinology, Metabolism and Internal Medicine, Poznan University of Medical Sciences, 60-356 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Micha\u0142","family":"Bartecki","sequence":"additional","affiliation":[{"name":"Department of Pediatric Cardiology, Poznan University of Medical Science, 60-572 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4091-7035","authenticated-orcid":false,"given":"Marta","family":"Kara\u017aniewicz-\u0141ada","sequence":"additional","affiliation":[{"name":"Department of Physical Pharmacy and Pharmacokinetics, Poznan University of Medical Sciences, 60-781 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"744","DOI":"10.3945\/jn.111.149393","article-title":"Global Iodine Status in 2011 and Trends over the Past Decade","volume":"142","author":"Andersson","year":"2012","journal-title":"J. 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