{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,20]],"date-time":"2026-01-20T05:17:16Z","timestamp":1768886236387,"version":"3.49.0"},"reference-count":23,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2018,9,1]],"date-time":"2018-09-01T00:00:00Z","timestamp":1535760000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100010663","name":"H2020 European Research Council","doi-asserted-by":"publisher","award":["669768"],"award-info":[{"award-number":["669768"]}],"id":[{"id":"10.13039\/100010663","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A ruthenium oxide (RuOx) sensor for potentiometric pH sensing is currently being developed for organs-on-chip purposes. The sensor was fabricated from a Ru(OH)3 precursor, resulting in RuOx nanorods after heating. An open-circuit potential of the RuOx electrode showed a near-Nernstian response of \u221258.05 mV\/pH, with good selectivity against potentially interfering ions (lithium, sulfate, chloride, and calcium ions). The preconditioned electrode (stored in liquid) had a long-term drift of \u22120.8 mV\/h, and its response rate was less than 2 s. Sensitivity to oxygen was observed at an order of magnitude lower than other reported metal-oxide pH sensors. Together with miniaturizability, the RuOx pH sensor proves to be a suitable pH sensor for organs-on-chip studies.<\/jats:p>","DOI":"10.3390\/s18092901","type":"journal-article","created":{"date-parts":[[2018,9,3]],"date-time":"2018-09-03T10:50:51Z","timestamp":1535971851000},"page":"2901","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":29,"title":["Ruthenium Oxide Nanorods as Potentiometric pH Sensor for Organs-On-Chip Purposes"],"prefix":"10.3390","volume":"18","author":[{"given":"Esther","family":"Tanumihardja","sequence":"first","affiliation":[{"name":"BIOS Lab on a Chip Group, Technical Medical Centre, MESA + Institute for Nanotechnology, and Max Planck Center for Complex Fluid Dynamics, University of Twente, 7522 NB Enschede, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7018-1383","authenticated-orcid":false,"given":"Wouter","family":"Olthuis","sequence":"additional","affiliation":[{"name":"BIOS Lab on a Chip Group, Technical Medical Centre, MESA + Institute for Nanotechnology, and Max Planck Center for Complex Fluid Dynamics, University of Twente, 7522 NB Enschede, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Albert","family":"Van den Berg","sequence":"additional","affiliation":[{"name":"BIOS Lab on a Chip Group, Technical Medical Centre, MESA + Institute for Nanotechnology, and Max Planck Center for Complex Fluid Dynamics, University of Twente, 7522 NB Enschede, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,9,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"760","DOI":"10.1038\/nbt.2989","article-title":"Microfluidic organs-on-chips","volume":"32","author":"Bhatia","year":"2014","journal-title":"Nat. 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