{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T15:43:53Z","timestamp":1768405433988,"version":"3.49.0"},"reference-count":35,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2024,2,5]],"date-time":"2024-02-05T00:00:00Z","timestamp":1707091200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["2022.08713.PTDC NORTE-07-0162-FEDER-000048"],"award-info":[{"award-number":["2022.08713.PTDC NORTE-07-0162-FEDER-000048"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["PTDC\/QUI-QIN\/28142\/2017"],"award-info":[{"award-number":["PTDC\/QUI-QIN\/28142\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/50016\/2020"],"award-info":[{"award-number":["UIDB\/50016\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/50006\/2020"],"award-info":[{"award-number":["UIDB\/50006\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["UIDP\/50006\/2020"],"award-info":[{"award-number":["UIDP\/50006\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Iodine is an essential micronutrient for humans due to its fundamental role in the biosynthesis of thyroid hormones. As a key parameter to assess health conditions, iodine intake needs to be monitored to ascertain and prevent iodine deficiency. Iodine is available from various food sources (such as seaweed, fish, and seafood, among others) and dietary supplements (multivitamins or mineral supplements). In this work, a microfluidic paper-based analytical device (\u03bcPAD) to quantify iodide in seaweed and dietary supplements is described. The developed \u03bcPAD is a small microfluidic device that emerges as quite relevant in terms of its analytical capacity. The quantification of iodide is based on the oxidation of 3,3\u2032,5,5\u2032-tetramethylbenzidine (TMB) by hydrogen peroxide in the presence of iodine, which acts as the catalyst to produce the blue form of TMB. Additionally, powder silica was used to intensify and uniformize the colour of the obtained product. Following optimization, the developed \u03bcPAD enabled iodide quantification within the range of 10\u2013100 \u00b5M, with a detection limit of 3 \u00b5M, and was successfully applied to seaweeds and dietary supplements. The device represents a valuable tool for point-of-care analysis, can be used by untrained personnel at home, and is easily disposable, low-cost, and user-friendly.<\/jats:p>","DOI":"10.3390\/s24031024","type":"journal-article","created":{"date-parts":[[2024,2,5]],"date-time":"2024-02-05T05:22:44Z","timestamp":1707110564000},"page":"1024","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Microfluidic Paper-Based Device Incorporated with Silica Nanoparticles for Iodide Quantification in Marine Source Dietary Supplements"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2952-3510","authenticated-orcid":false,"given":"Mafalda G.","family":"Pereira","sequence":"first","affiliation":[{"name":"CBQF\u2014Centro de Biotecnologia e Qu\u00edmica Fina, Laborat\u00f3rio Associado, Escola Superior de Biotecnologia, Universidade Cat\u00f3lica Portuguesa, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0732-1571","authenticated-orcid":false,"given":"Ana","family":"Machado","sequence":"additional","affiliation":[{"name":"ICBAS\u2014Instituto de Ci\u00eancias Biom\u00e9dicas Abel Salazar, University of Porto, Rua Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal"},{"name":"CIIMAR\u2014Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Novo Edif\u00edcio do Terminal de Cruzeiros do Porto de Leix\u00f5es, Avenida General Norton de Matos, S\/N, 4450-208 Matosinhos, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1967-8853","authenticated-orcid":false,"given":"Andreia","family":"Leite","sequence":"additional","affiliation":[{"name":"REQUIMTE-LAQV, Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias, Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0998-1437","authenticated-orcid":false,"given":"Maria","family":"Rangel","sequence":"additional","affiliation":[{"name":"REQUIMTE-LAQV, Instituto de Ci\u00eancias Biom\u00e9dicas de Abel Salazar, Universidade do Porto, Rua Jorge Viterbo, 4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9637-6541","authenticated-orcid":false,"given":"Adriano","family":"Bordalo","sequence":"additional","affiliation":[{"name":"ICBAS\u2014Instituto de Ci\u00eancias Biom\u00e9dicas Abel Salazar, University of Porto, Rua Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal"},{"name":"CIIMAR\u2014Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Novo Edif\u00edcio do Terminal de Cruzeiros do Porto de Leix\u00f5es, Avenida General Norton de Matos, S\/N, 4450-208 Matosinhos, Portugal"}]},{"given":"Ant\u00f3nio O. S. S.","family":"Rangel","sequence":"additional","affiliation":[{"name":"CBQF\u2014Centro de Biotecnologia e Qu\u00edmica Fina, Laborat\u00f3rio Associado, Escola Superior de Biotecnologia, Universidade Cat\u00f3lica Portuguesa, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7745-1860","authenticated-orcid":false,"given":"Raquel B. R.","family":"Mesquita","sequence":"additional","affiliation":[{"name":"CBQF\u2014Centro de Biotecnologia e Qu\u00edmica Fina, Laborat\u00f3rio Associado, Escola Superior de Biotecnologia, Universidade Cat\u00f3lica Portuguesa, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"497","DOI":"10.2116\/analsci.26.497","article-title":"Kinetic Spectrophotometric Determination of Trace Amounts of iodide in Food Samples","volume":"26","author":"Shishehbore","year":"2010","journal-title":"Anal. Sci."},{"key":"ref_2","unstructured":"Aburto, N.J., Abudou, M., Candeias, V., and Tiaxiang Wu, P. (2014). 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