{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,8]],"date-time":"2025-11-08T22:51:35Z","timestamp":1762642295953,"version":"build-2065373602"},"reference-count":39,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2019,12,4]],"date-time":"2019-12-04T00:00:00Z","timestamp":1575417600000},"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 a Tecnologia","doi-asserted-by":"publisher","award":["PTDC\/FIS-NAN\/0909\/2014","UID\/FIS\/00068\/2019","UID\/AMB\/04085\/2019","SFRH\/BD\/114674\/2016."],"award-info":[{"award-number":["PTDC\/FIS-NAN\/0909\/2014","UID\/FIS\/00068\/2019","UID\/AMB\/04085\/2019","SFRH\/BD\/114674\/2016."]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Marie Sk\u0142odowska-Curie","award":["No. 778045"],"award-info":[{"award-number":["No. 778045"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Triclosan, which is a bacteriostatic used in household items, has raised health concerns, because it might lead to antimicrobial resistance and endocrine disorders in organisms. The detection, identification, and monitoring of triclosan and its by-products (methyl triclosan, 2,4-Dichlorophenol and 2,4,6-Trichlorophenol) are a growing need in order to update current water treatments and enable the continuous supervision of the contamination plume. This work presents a customized electronic tongue prototype coupled to an electrochemical flow reactor, which aims to access the monitoring of triclosan and its derivative by-products in a real secondary effluent. An electronic tongue device, based on impedance measurements and polyethylenimine\/poly(sodium 4-styrenesulfonate) layer-by-layer and TiO2, ZnO and TiO2\/ZnO sputtering thin films, was developed and tested to track analyte degradation and allow for analyte detection and semi-quantification. A degradation pathway trend was observable by means of principal component analysis, being the sample separation, according to sampling time, explained by 77% the total variance in the first two components. A semi-quantitative electronic tongue was attained for triclosan and methyl-triclosan. For 2,4-Dichlorophenol and 2,4,6-Trichlorophenol, the best results were achieved with only a single sensor. Finally, working as multi-analyte quantification devices, the electronic tongues could provide information regarding the degradation kinetic and concentrations ranges in a dynamic removal treatment.<\/jats:p>","DOI":"10.3390\/s19245349","type":"journal-article","created":{"date-parts":[[2019,12,5]],"date-time":"2019-12-05T03:16:36Z","timestamp":1575515796000},"page":"5349","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Electronic Tongue Coupled to an Electrochemical Flow Reactor for Emerging Organic Contaminants Real Time Monitoring"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5667-4819","authenticated-orcid":false,"given":"C\u00e1tia","family":"Magro","sequence":"first","affiliation":[{"name":"CENSE, Department of Sciences and Environmental Engineering, NOVA School of Science and Technology, NOVA University Lisbon, Caparica Campus, 2829-516 Caparica, Portugal"}]},{"given":"Eduardo P.","family":"Mateus","sequence":"additional","affiliation":[{"name":"CENSE, Department of Sciences and Environmental Engineering, NOVA School of Science and Technology, NOVA University Lisbon, Caparica Campus, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1464-6975","authenticated-orcid":false,"given":"Juan M.","family":"Paz-Garcia","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Faculty of Sciences, University of Malaga, Teatinos Campus, 29010 Malaga, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8086-7792","authenticated-orcid":false,"given":"Susana","family":"S\u00e9rio","sequence":"additional","affiliation":[{"name":"CEFITEC, Department of Physics, NOVA School of Science and Technology, NOVA University Lisbon, Caparica Campus, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4710-0693","authenticated-orcid":false,"given":"Maria","family":"Raposo","sequence":"additional","affiliation":[{"name":"CEFITEC, Department of Physics, NOVA School of Science and Technology, NOVA University Lisbon, Caparica Campus, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5606-3591","authenticated-orcid":false,"given":"Alexandra B.","family":"Ribeiro","sequence":"additional","affiliation":[{"name":"CENSE, Department of Sciences and Environmental Engineering, NOVA School of Science and Technology, NOVA University Lisbon, Caparica Campus, 2829-516 Caparica, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2019,12,4]]},"reference":[{"key":"ref_1","unstructured":"United Nations (2019). 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