{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T17:21:45Z","timestamp":1779384105926,"version":"3.53.1"},"reference-count":30,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2020,5,30]],"date-time":"2020-05-30T00:00:00Z","timestamp":1590796800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100015015","name":"Government of South Australia","doi-asserted-by":"publisher","award":["IVP129"],"award-info":[{"award-number":["IVP129"]}],"id":[{"id":"10.13039\/100015015","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100015015","name":"Government of South Australia","doi-asserted-by":"publisher","award":["FIA003"],"award-info":[{"award-number":["FIA003"]}],"id":[{"id":"10.13039\/100015015","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000969","name":"Australian Academy of Science","doi-asserted-by":"publisher","award":["Regional Collaborations Programme"],"award-info":[{"award-number":["Regional Collaborations Programme"]}],"id":[{"id":"10.13039\/501100000969","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A microfluidic sensor was studied for the photometric detection of active chlorine, total chlorine, and pH in swimming pool samples. The sensor consisted of a four-layer borosilicate glass chip, containing a microchannel network and a 2.2 mm path length, 1.7 mL optical cell. The chip was optimised to measure the bleaching of methyl orange and spectral changes in phenol red for quantitative chlorine (active and total) and pH measurements that were suited to swimming pool monitoring. Reagent consumption (60 mL per measurement) was minimised to allow for maintenance-free operation over a nominal summer season (3 months) with minimal waste. The chip was tested using samples from 12 domestic, public, and commercial swimming pools (indoor and outdoor), with results that compare favourably with commercial products (test strips and the N,N\u2019-diethyl-p-phenylenediamine (DPD) method), precision pH electrodes, and iodometric titration.<\/jats:p>","DOI":"10.3390\/s20113099","type":"journal-article","created":{"date-parts":[[2020,6,2]],"date-time":"2020-06-02T09:19:27Z","timestamp":1591089567000},"page":"3099","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":35,"title":["Photometric Sensing of Active Chlorine, Total Chlorine, and pH on a Microfluidic Chip for Online Swimming Pool Monitoring"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1235-1436","authenticated-orcid":false,"given":"Sait","family":"Elmas","sequence":"first","affiliation":[{"name":"Future Industries Institute, University of South Australia, Mawson Lakes, SA 5095, Australia"},{"name":"Institute for Nanoscale Science &amp; Technology, College of Science &amp; Engineering, Flinders University, Sturt Road, Bedford Park, SA 5042, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aneta","family":"Pospisilova","sequence":"additional","affiliation":[{"name":"Future Industries Institute, University of South Australia, Mawson Lakes, SA 5095, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aneta Anna","family":"Sekulska","sequence":"additional","affiliation":[{"name":"Future Industries Institute, University of South Australia, Mawson Lakes, SA 5095, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vasil","family":"Vasilev","sequence":"additional","affiliation":[{"name":"Future Industries Institute, University of South Australia, Mawson Lakes, SA 5095, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2723-6553","authenticated-orcid":false,"given":"Thomas","family":"Nann","sequence":"additional","affiliation":[{"name":"Future Industries Institute, University of South Australia, Mawson Lakes, SA 5095, Australia"},{"name":"School of Mathematical and Physical Sciences, University of Newcastle, University Drive, Callaghan, NSW 2308, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stephen","family":"Thornton","sequence":"additional","affiliation":[{"name":"Tekelek Australia Pty Ltd., 95A Bedford St, Gillman SA 5013, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8861-2161","authenticated-orcid":false,"given":"Craig","family":"Priest","sequence":"additional","affiliation":[{"name":"Future Industries Institute, University of South Australia, Mawson Lakes, SA 5095, Australia"},{"name":"School of Engineering, University of South Australia, Mawson Lakes, SA 5095, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,5,30]]},"reference":[{"key":"ref_1","unstructured":"Swimming Pool and Spa Water Chemistry (2020, April 28). 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