{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,25]],"date-time":"2026-03-25T11:21:22Z","timestamp":1774437682074,"version":"3.50.1"},"reference-count":30,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2017,7,19]],"date-time":"2017-07-19T00:00:00Z","timestamp":1500422400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Monitoring of the pH, oxidation-reduction-potential (ORP), and conductivity of aqueous samples is typically performed using multiple sensors. To minimize the size and cost of these sensors for practical applications, we have investigated the use of a single sensor constructed with only bare platinum electrodes deposited on a glass substrate. The sensor can measure pH from 4 to 10 while simultaneously measuring ORP from 150 to 800 mV. The device can also measure conductivity up to 8000 \u03bcS\/cm in the range of 10 \u00b0C to 50 \u00b0C, and all these measurements can be made even if the water samples contain common ions found in residential water. The sensor is inexpensive (i.e., ~$0.10\/unit) and has a sensing area below 1 mm2, suggesting that the unit is cost-efficient, robust, and widely applicable, including in microfluidic systems.<\/jats:p>","DOI":"10.3390\/s17071655","type":"journal-article","created":{"date-parts":[[2017,7,20]],"date-time":"2017-07-20T04:28:26Z","timestamp":1500524906000},"page":"1655","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Multifunctional Water Sensors for pH, ORP, and Conductivity Using Only Microfabricated Platinum Electrodes"],"prefix":"10.3390","volume":"17","author":[{"given":"Wen-Chi","family":"Lin","sequence":"first","affiliation":[{"name":"Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Klaus","family":"Brondum","sequence":"additional","affiliation":[{"name":"Masco Corporation, Taylor, MI 48180, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Charles","family":"Monroe","sequence":"additional","affiliation":[{"name":"Department of Engineering Science, University of Oxford, Oxford OX1 3PJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mark","family":"Burns","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109, USA"},{"name":"Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,7,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7333","DOI":"10.3390\/ijerph110707333","article-title":"Comparison and Cost Analysis of Drinking Water Quality Monitoring Requirements versus Practice in Seven Developing Countries","volume":"11","author":"Crocker","year":"2014","journal-title":"Int. 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