{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T00:02:47Z","timestamp":1768435367238,"version":"3.49.0"},"reference-count":21,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2022,11,25]],"date-time":"2022-11-25T00:00:00Z","timestamp":1669334400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Croatian Science Foundation","award":["IP-2019-04-8846"],"award-info":[{"award-number":["IP-2019-04-8846"]}]},{"name":"Croatian Science Foundation","award":["UNIRI-prirod-18-102"],"award-info":[{"award-number":["UNIRI-prirod-18-102"]}]},{"name":"University of Rijeka","award":["IP-2019-04-8846"],"award-info":[{"award-number":["IP-2019-04-8846"]}]},{"name":"University of Rijeka","award":["UNIRI-prirod-18-102"],"award-info":[{"award-number":["UNIRI-prirod-18-102"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A low-cost and fast potentiometric surfactant sensor for cationic surfactants, based on the new ion-pair 1,3-dioctadecyl-1H-imidazol-3-ium-tetraphenylborate (DODI-TPB), is presented. The new cationic surfactant DODI-Br was synthesized and characterized by NMR, LC-MS, and elemental analysis, and was used for synthesis of the DODI-TPB ionophore. The DODI-TPB surfactant sensor was obtained by implementation of the ionophore in PVC. The sensor showed excellent response characteristics with near-Nernstian slopes to the cationic surfactants DMIC, CPC, CTAB, and Hyamine 1622. The highest voltage responses were obtained for DMIC and CPC (58.7 mV\/decade of activity). DMIC had the lowest detection limit (0.9 \u00d7 10\u22126 M) and the broadest useful linear concentration range (1.8 \u00d7 10\u22126 to 1.0 \u00d7 10\u22124 M). An interference study showed remarkable stability. Potentiometric titration curves for the titration of cationic surfactants (DMIC, CPC, CTAB, and Hyamine 1622), with DDS and TPB used as titrants, showed sigmoidal curves with well-defined inflexion points and a broad signal change. The standard addition method was successfully applied with recovery rates from 98.9 to 101.2 at two concentrations. The amount of cationic surfactant found in disinfectants and antiseptics was in good agreement with the referent two-phase titration method and the surfactant sensor on the market. This new surfactant sensor represents a low-cost alternative to existing methods for cationic surfactant detection.<\/jats:p>","DOI":"10.3390\/s22239141","type":"journal-article","created":{"date-parts":[[2022,11,25]],"date-time":"2022-11-25T03:34:24Z","timestamp":1669347264000},"page":"9141","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["The 1,3-Dioctadecyl-1H-imidazol-3-ium Based Potentiometric Surfactant Sensor for Detecting Cationic Surfactants in Commercial Products"],"prefix":"10.3390","volume":"22","author":[{"given":"Nikola","family":"Saka\u010d","sequence":"first","affiliation":[{"name":"Faculty of Geotechnical Engineering, University of Zagreb, 42000 Vara\u017edin, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dubravka","family":"Maduni\u0107-\u010ca\u010di\u0107","sequence":"additional","affiliation":[{"name":"Faculty of Geotechnical Engineering, University of Zagreb, 42000 Vara\u017edin, Croatia"},{"name":"Saponia Chemical, Pharmaceutical and Foodstuff Industry, Inc., 31000 Osijek, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6218-973X","authenticated-orcid":false,"given":"Dean","family":"Markovi\u0107","sequence":"additional","affiliation":[{"name":"Department of Biotechnology, University of Rijeka, 51000 Rijeka, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2920-6187","authenticated-orcid":false,"given":"Bartolomeo Della","family":"Ventura","sequence":"additional","affiliation":[{"name":"Department of Physics \u201cE. Pancini\u201d, Universit\u00e0 Di Napoli Federico II, 80126 Napoli, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1077-8353","authenticated-orcid":false,"given":"Raffaele","family":"Velotta","sequence":"additional","affiliation":[{"name":"Department of Physics \u201cE. Pancini\u201d, Universit\u00e0 Di Napoli Federico II, 80126 Napoli, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anita","family":"Pti\u010dek Siro\u010di\u0107","sequence":"additional","affiliation":[{"name":"Faculty of Geotechnical Engineering, University of Zagreb, 42000 Vara\u017edin, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5727-0613","authenticated-orcid":false,"given":"Brunislav","family":"Matasovi\u0107","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Osijek, 31000 Osijek, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nikolina","family":"Sermek","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Osijek, 31000 Osijek, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2361-8036","authenticated-orcid":false,"given":"Bojan","family":"\u0110urin","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering, University North, 42000 Vara\u017edin, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1567-6455","authenticated-orcid":false,"given":"Bojan","family":"\u0160arkanj","sequence":"additional","affiliation":[{"name":"Department of Food Technology, University North, 48000 Koprivnica, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9509-8105","authenticated-orcid":false,"given":"Marija","family":"Jozanovi\u0107","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Osijek, 31000 Osijek, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"149230","DOI":"10.1016\/j.scitotenv.2021.149230","article-title":"Change in the chemical content of untreated wastewater of Athens, Greece under COVID-19 pandemic","volume":"799","author":"Alygizakis","year":"2021","journal-title":"Sci. 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