{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T04:08:35Z","timestamp":1784779715946,"version":"3.55.0"},"reference-count":38,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2018,2,13]],"date-time":"2018-02-13T00:00:00Z","timestamp":1518480000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Science Foundation of China","doi-asserted-by":"publisher","award":["21574061 and 21604036"],"award-info":[{"award-number":["21574061 and 21604036"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Shenzhen fundamental research programs","award":["JCYJ20150630145302243"],"award-info":[{"award-number":["JCYJ20150630145302243"]}]},{"name":"start fund of SUSTech","award":["FRG-SUSTC1501A-01, Y01256009"],"award-info":[{"award-number":["FRG-SUSTC1501A-01, Y01256009"]}]},{"name":"Shenzhen Science and Technology Innovation Committee for key laboratory","award":["ZDSYS20140509142721431"],"award-info":[{"award-number":["ZDSYS20140509142721431"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this study, we developed fluorescent dual pH and oxygen sensors loaded in multi-well plates for in-situ and high-throughput monitoring of oxygen respiration and extracellular acidification during microbial cell growth for understanding metabolism. Biocompatible PHEMA-co-PAM materials were used as the hydrogel matrix. A polymerizable oxygen probe (OS2) derived from PtTFPP and a polymerizable pH probe (S2) derived from fluorescein were chemically conjugated into the matrix to solve the problem of the probe leaching from the matrix. Gels were allowed to cure directly on the bottom of 96-well plates at room-temperature via redox polymerization. The influence of matrix\u2019s composition on the sensing behaviors was investigated to optimize hydrogels with enough robustness for repeatable use with good sensitivity. Responses of the dual sensing hydrogels to dissolved oxygen (DO) and pH were studied. These dual oxygen-pH sensing plates were successfully used for microbial cell-based screening assays, which are based on the measurement of fluorescence intensity changes induced by cellular oxygen consumption and pH changes during microbial growth. This method may provide a real-time monitoring of cellular respiration, acidification, and a rapid kinetic assessment of multiple samples for cell viability as well as high-throughput drug screening. All of these assays can be carried out by a conventional plate reader.<\/jats:p>","DOI":"10.3390\/s18020564","type":"journal-article","created":{"date-parts":[[2018,2,13]],"date-time":"2018-02-13T05:32:19Z","timestamp":1518499939000},"page":"564","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":40,"title":["Hydrogel-Based Fluorescent Dual pH and Oxygen Sensors Loaded in 96-Well Plates for High-Throughput Cell Metabolism Studies"],"prefix":"10.3390","volume":"18","author":[{"given":"Shanshan","family":"Wu","sequence":"first","affiliation":[{"name":"Department of Materials Science and Engineering, Southern University of Science and Technology, No 1088 Xueyuan Road, Xili, Nanshan District, Shenzhen 518055, China"},{"name":"Department of Physics, Wuhan University, Wuhan 430072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Siying","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Southern University of Science and Technology, No 1088 Xueyuan Road, Xili, Nanshan District, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zheyuan","family":"Yi","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Southern University of Science and Technology, No 1088 Xueyuan Road, Xili, Nanshan District, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fei","family":"Zeng","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Southern University of Science and Technology, No 1088 Xueyuan Road, Xili, Nanshan District, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Weizhen","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Southern University of Science and Technology, No 1088 Xueyuan Road, Xili, Nanshan District, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuan","family":"Qiao","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Southern University of Science and Technology, No 1088 Xueyuan Road, Xili, Nanshan District, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xingzhong","family":"Zhao","sequence":"additional","affiliation":[{"name":"Department of Physics, Wuhan University, Wuhan 430072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2704-1323","authenticated-orcid":false,"given":"Xing","family":"Cheng","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Southern University of Science and Technology, No 1088 Xueyuan Road, Xili, Nanshan District, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1441-2431","authenticated-orcid":false,"given":"Yanqing","family":"Tian","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Southern University of Science and Technology, No 1088 Xueyuan Road, Xili, Nanshan District, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,2,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1016\/0166-2236(93)90117-5","article-title":"Do defecs in mitochondrial energy metabolism underlie the pathology of neurodegenerative diseases?","volume":"16","author":"Beal","year":"1993","journal-title":"Trends Neurosci."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1016\/S0022-0981(98)00139-7","article-title":"The effect of dissolved oxygen and salinity on oxygen consumption, ammonia excretion and osmotic pressure of Penaeus setiferus (Linnaeus) juveniles","volume":"234","author":"Rosas","year":"1999","journal-title":"J. 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