{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,22]],"date-time":"2026-10-22T20:47:24Z","timestamp":1792702044717,"version":"4.5.0"},"reference-count":38,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2025,7,23]],"date-time":"2025-07-23T00:00:00Z","timestamp":1753228800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Dutch Research Council (NWO)","award":["SEDAS 18271"],"award-info":[{"award-number":["SEDAS 18271"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We present a novel method to estimate blood cortisol concentration from sweat cortisol measurements, incorporating a kinetic model to simulate cortisol transport dynamics. Cortisol dysregulation is observed in conditions like Cushing\u2019s syndrome, characterized by excessive cortisol production, and stress-related disorders, which can lead to metabolic disturbances, anxiety, and impaired overall health. Sweat-sensing technology offers a non-invasive and continuous alternative to blood sampling. However, the limited research exploring the sweat\u2013blood cortisol relationship in patients shows a moderate correlation (R&lt;0.6), hindering its clinical application for long-term monitoring. In this paper, we propose a novel kinetic model describing cortisol transport from blood to sweat. The model was validated using data from 44 patients before and after cardiac surgery. A high Pearson correlation coefficient of 0.95 (95% CI: 0.92\u20130.97) was observed between our model\u2019s estimated and experimental blood cortisol concentrations. Moreover, the method enables personalized estimation of physiological parameters, accurately reflecting patients\u2019 status under varying clinical conditions. The method paves the way for the clinical application of long-term, non-invasive monitoring of cortisol using sweat-sensing technology. Enabling the personalized estimation of physiological parameters could potentially support clinical decision-making, helping doctors diagnose and monitor patients with health conditions involving cortisol dysregulation.<\/jats:p>","DOI":"10.3390\/s25154551","type":"journal-article","created":{"date-parts":[[2025,7,23]],"date-time":"2025-07-23T08:02:06Z","timestamp":1753257726000},"page":"4551","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Non-Invasive Blood Cortisol Estimation from Sweat Analysis by Kinetic Modeling of Cortisol Transport Dynamics"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-2713-8450","authenticated-orcid":false,"given":"Xiaoyu","family":"Yin","sequence":"first","affiliation":[{"name":"Department of Electrical Engineering, Eindhoven University of Technology, 5612 AZ Eindhoven, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sophie","family":"Adelaars","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Eindhoven University of Technology, 5612 AZ Eindhoven, The Netherlands"},{"name":"Catharina Hospital, 5623 EJ Eindhoven, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1231-9372","authenticated-orcid":false,"given":"Elisabetta","family":"Peri","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Eindhoven University of Technology, 5612 AZ Eindhoven, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eduard","family":"Pelssers","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Eindhoven University of Technology, 5612 AZ Eindhoven, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5923-4456","authenticated-orcid":false,"given":"Jaap","family":"den Toonder","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Eindhoven University of Technology, 5612 AZ Eindhoven, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arthur","family":"Bouwman","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Eindhoven University of Technology, 5612 AZ Eindhoven, The Netherlands"},{"name":"Catharina Hospital, 5623 EJ Eindhoven, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0126-4695","authenticated-orcid":false,"given":"Daan","family":"van de Kerkhof","sequence":"additional","affiliation":[{"name":"Catharina Hospital, 5623 EJ Eindhoven, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1179-5385","authenticated-orcid":false,"given":"Massimo","family":"Mischi","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Eindhoven University of Technology, 5612 AZ Eindhoven, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1526","DOI":"10.1210\/jc.2008-0125","article-title":"The Diagnosis of Cushing\u2019s Syndrome: An Endocrine Society Clinical Practice Guideline","volume":"93","author":"Nieman","year":"2008","journal-title":"J. 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