{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,8]],"date-time":"2026-03-08T23:50:23Z","timestamp":1773013823046,"version":"3.50.1"},"reference-count":44,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2020,12,24]],"date-time":"2020-12-24T00:00:00Z","timestamp":1608768000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003593","name":"Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico","doi-asserted-by":"publisher","award":["CNPq \u2013 430121\/2016-4 and CNPq - 306323\/2018-4"],"award-info":[{"award-number":["CNPq \u2013 430121\/2016-4 and CNPq - 306323\/2018-4"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001807","name":"Funda\u00e7\u00e3o de Amparo \u00e0 Pesquisa do Estado de S\u00e3o Paulo","doi-asserted-by":"publisher","award":["FAPESP 2014\/50945-4"],"award-info":[{"award-number":["FAPESP 2014\/50945-4"]}],"id":[{"id":"10.13039\/501100001807","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002322","name":"Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior","doi-asserted-by":"publisher","award":["CAPES 88887136426\/2017\/00"],"award-info":[{"award-number":["CAPES 88887136426\/2017\/00"]}],"id":[{"id":"10.13039\/501100002322","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["PIDDAC"],"award-info":[{"award-number":["PIDDAC"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>This study aims to investigate the applicability of a hybrid electrochemical sensor composed of cork and graphite (Gr) for detecting caffeine in aqueous solutions. Raw cork (RAC) and regranulated cork (RGC, obtained by thermal treatment of RAC with steam at 380 \u00b0C) were tested as modifiers. The results clearly showed that the cork-graphite sensors, GrRAC and GrRGC, exhibited a linear response over a wide range of caffeine concentration (5\u20131000 \u00b5M), with R2 of 0.99 and 0.98, respectively. The limits of detection (LOD), estimated at 2.9 and 6.1 \u00b5M for GrRAC and GrRGC, suggest greater sensitivity and reproducibility than the unmodified conventional graphite sensor. The low-cost cork-graphite sensors were successfully applied in the determination of caffeine in soft drinks and pharmaceutical formulations, presenting well-defined current signals when analyzing real samples. When comparing electrochemical determinations and high performance liquid chromatography measurements, no significant differences were observed (mean accuracy 3.0%), highlighting the potential use of these sensors to determine caffeine in different samples.<\/jats:p>","DOI":"10.3390\/ma14010037","type":"journal-article","created":{"date-parts":[[2020,12,24]],"date-time":"2020-12-24T09:02:44Z","timestamp":1608800564000},"page":"37","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["Applicability of Cork as Novel Modifiers to Develop Electrochemical Sensor for Caffeine Determination"],"prefix":"10.3390","volume":"14","author":[{"given":"Mayra","family":"Monteiro","sequence":"first","affiliation":[{"name":"Laborat\u00f3rio de Eletroqu\u00edmica Ambiental e Aplicada, Universidade Federal do Rio Grande do Norte, Lagoa Nova 59.072-900, Brazil"}]},{"given":"Djalma","family":"Da Silva","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Eletroqu\u00edmica Ambiental e Aplicada, Universidade Federal do Rio Grande do Norte, Lagoa Nova 59.072-900, Brazil"}]},{"given":"Marco","family":"Quiroz","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Eletroqu\u00edmica Ambiental e Aplicada, Universidade Federal do Rio Grande do Norte, Lagoa Nova 59.072-900, Brazil"},{"name":"Grupo de Investigaci\u00f3n en Energ\u00eda y Ambiente, Universidad de las Am\u00e9ricas Puebla, ExHda. Sta. Catarina Martir, Cholula 72820, Mexico"}]},{"given":"V\u00edtor","family":"Vilar","sequence":"additional","affiliation":[{"name":"Laboratory of Separation and Reaction Engineering-Laboratory of Catalysis and Materials (LSRE-LCM), Chemical Engineering Department, Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6209-5426","authenticated-orcid":false,"given":"Carlos","family":"Mart\u00ednez-Huitle","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Eletroqu\u00edmica Ambiental e Aplicada, Universidade Federal do Rio Grande do Norte, Lagoa Nova 59.072-900, Brazil"},{"name":"National Institute for Alternative Technologies of Detection, Toxicological Evaluation and Removal of Micropollutants and Radioactives (INCT-DATREM), Institute of Chemistry, UNESP, P.O. Box 355, Araraquara 14800 900, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2189-5694","authenticated-orcid":false,"given":"Elisama","family":"Dos Santos","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Eletroqu\u00edmica Ambiental e Aplicada, Universidade Federal do Rio Grande do Norte, Lagoa Nova 59.072-900, Brazil"},{"name":"National Institute for Alternative Technologies of Detection, Toxicological Evaluation and Removal of Micropollutants and Radioactives (INCT-DATREM), Institute of Chemistry, UNESP, P.O. Box 355, Araraquara 14800 900, Brazil"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,24]]},"reference":[{"key":"ref_1","first-page":"1","article-title":"Acute doses of caffeine shift nervous system cell expression profiles toward promotion of neuronal projection growth","volume":"7","author":"Yu","year":"2017","journal-title":"Sci. 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