{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,23]],"date-time":"2026-06-23T23:10:22Z","timestamp":1782256222447,"version":"3.54.5"},"reference-count":33,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2022,3,4]],"date-time":"2022-03-04T00:00:00Z","timestamp":1646352000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"German Ministry of Economic Affairs and Energy","award":["KF2130904RH4"],"award-info":[{"award-number":["KF2130904RH4"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>With the increasing demand for ultrapure water in the pharmaceutical and semiconductor industry, the need for precise measuring instruments for those applications is also growing. One critical parameter of water quality is the amount of total organic carbon (TOC). This work presents a system that uses the advantage of the increased oxidation power achieved with UV\/O3 advanced oxidation process (AOP) for TOC measurement in combination with a significant miniaturization compared to the state of the art. The miniaturization is achieved by using polymer-electrolyte membrane (PEM) electrolysis cells for ozone generation in combination with UV-LEDs for irradiation of the measuring solution, as both components are significantly smaller than standard equipment. Conductivity measurement after oxidation is the measuring principle and measurements were carried out in the TOC range between 10 and 1000 ppb TOC. The suitability of the system for TOC measurement is demonstrated using the oxidation by ozonation combined with UV irradiation of defined concentrations of isopropyl alcohol (IPA).<\/jats:p>","DOI":"10.3390\/s22052004","type":"journal-article","created":{"date-parts":[[2022,3,6]],"date-time":"2022-03-06T20:40:02Z","timestamp":1646599202000},"page":"2004","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["A New Setup for the Measurement of Total Organic Carbon in Ultrapure Water Systems"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3372-8845","authenticated-orcid":false,"given":"Sara H.","family":"Sch\u00e4fer","sequence":"first","affiliation":[{"name":"Department of Natural Science, Safety and Security Research Institute, Bonn-Rhein-Sieg University of Applied Science, 53359 Rheinbach, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katharina","family":"van Dyk","sequence":"additional","affiliation":[{"name":"Innovatec Ger\u00e4tetechnik GmbH, 53359 Rheinbach, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5169-7010","authenticated-orcid":false,"given":"Johannes","family":"Warmer","sequence":"additional","affiliation":[{"name":"Innovatec Ger\u00e4tetechnik GmbH, 53359 Rheinbach, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1107-4403","authenticated-orcid":false,"given":"Torsten C.","family":"Schmidt","sequence":"additional","affiliation":[{"name":"Department of Instrumental Analytical Chemistry, University of Duisburg-Essen, 45147 Essen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8642-6253","authenticated-orcid":false,"given":"Peter","family":"Kaul","sequence":"additional","affiliation":[{"name":"Department of Natural Science, Safety and Security Research Institute, Bonn-Rhein-Sieg University of Applied Science, 53359 Rheinbach, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,3,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Ohlrogge, K., and Ebert, K. 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