{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,20]],"date-time":"2026-02-20T06:48:27Z","timestamp":1771570107114,"version":"3.50.1"},"reference-count":32,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2024,4,9]],"date-time":"2024-04-09T00:00:00Z","timestamp":1712620800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Science, Technological Development and Innovations of the Republic of Serbia","award":["451-03-66\/2024-03\/200124"],"award-info":[{"award-number":["451-03-66\/2024-03\/200124"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Two new surfactant sensors were developed by synthesizing Pt-doped acid-activated multi-walled carbon nanotubes (Pt@MWCNTs). Two different ionophores using Pt@MWCNTs, a new plasticizer, and (a) cationic surfactant 1,3-dihexadecyl-1H-benzo[d]imidazol-3-ium-DHBI (Pt@MWCNT-DHBI ionophore) and (b) anionic surfactant dodecylbenzenesulfonate-DBS (Pt@MWCNT-DBS ionophore) composites were successfully synthesized and characterized. Both surfactant sensors showed a response to anionic surfactants (dodecylsulfate (SDS) and DBS) and cationic surfactants (cetylpyridinium chloride (CPC) and hexadecyltrimethylammonium bromide (CTAB)). The Pt@MWCNT-DBS sensor showed lower sensitivity than expected with the sub-Nernstian response of \u224823 mV\/decade of activity for CPC and CTAB and \u224833 mV\/decade of activity for SDS and DBS. The Pt@MWCNT-DHBI surfactant sensor had superior response properties, including a Nernstian response to SDS (59.1 mV\/decade) and a near-Nernstian response to DBS (57.5 mV\/decade), with linear response regions for both anionic surfactants down to \u22482 \u00d7 10\u22126 M. The Pt@MWCNT-DHBI was also useful in critical micellar concentration (CMC) detection. Common anions showed very low interferences with the sensor. The sensor was successfully employed for the potentiometric titration of a technical grade cationic surfactant with good recoveries. The content of cationic surfactants was measured in six samples of complex commercial detergents. The Pt@MWCNT-DHBI surfactant sensor showed good agreement with the ISE surfactant sensor and classical two-phase titration and could be used as an analytical tool in quality control.<\/jats:p>","DOI":"10.3390\/s24082388","type":"journal-article","created":{"date-parts":[[2024,4,9]],"date-time":"2024-04-09T04:37:27Z","timestamp":1712637447000},"page":"2388","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Potentiometric Surfactant Sensor with a Pt-Doped Acid-Activated Multi-Walled Carbon Nanotube-Based Ionophore Nanocomposite"],"prefix":"10.3390","volume":"24","author":[{"given":"Nada","family":"Glumac","sequence":"first","affiliation":[{"name":"Me\u0111imurske Vode D.O.O., 40000 \u010cakovec, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Milan","family":"Mom\u010dilovi\u0107","sequence":"additional","affiliation":[{"name":"Faculty of Sciences and Mathematics, University of Ni\u0161, 18000 Ni\u0161, Serbia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9609-3218","authenticated-orcid":false,"given":"Iztok","family":"Kramberger","sequence":"additional","affiliation":[{"name":"Faculty of Electrical Engineering and Computer Science, University of Maribor, 2000 Maribor, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Darko","family":"\u0160traus","sequence":"additional","affiliation":[{"name":"Faculty of Electrical Engineering and Computer Science, University of Maribor, 2000 Maribor, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nikola","family":"Saka\u010d","sequence":"additional","affiliation":[{"name":"Faculty of Geotechnical Engineering, University of Zagreb, 42000 Vara\u017edin, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7473-5964","authenticated-orcid":false,"given":"Elvira","family":"Kova\u010d-Andri\u0107","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"}]},{"given":"Marija","family":"Kra\u0161evac Saka\u010d","sequence":"additional","affiliation":[{"name":"Faculty of Chemical Engineering and Technology, University of Zagreb, 10000 Zagreb, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-9726-8659","authenticated-orcid":false,"given":"Kristina","family":"\u0110ambi\u0107","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Osijek, 31000 Osijek, 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":[[2024,4,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1080\/10408340590947899","article-title":"Determination of anionic surfactants employing potentiometric sensors\u2014A review","volume":"35","year":"2005","journal-title":"Crit. 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