{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T09:50:29Z","timestamp":1777456229620,"version":"3.51.4"},"reference-count":48,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,1,5]],"date-time":"2021-01-05T00:00:00Z","timestamp":1609804800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61673368"],"award-info":[{"award-number":["61673368"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Conventional strategies for determining phosphate concentration is limited in efficiency due to the cost, time, and labor that is required in laboratory analysis. Therefore, an on-site and rapid detection sensor for phosphate is urgently needed to characterize phosphate variability in a hydroponic system. Cobalt (Co) is a highly sensitive metal that has shown a selectivity towards phosphate to a certain extent. A disposable phosphate sensor based on the screen-printed electrode (SPE) was developed to exploit the advantages of Co-nanoparticles. A support vector machine regression model was established to predict the concentration of phosphate in the hydroponic solutions. The results showed that Co-nanoparticles improve the detection limit of the sensor in the initial state. Meanwhile, the corrosion of Co-nanoparticles leads to a serious time-drift and instability of the electrodes. On the other hand, the coefficient of variation of the disposable phosphate detection chip is 0.4992%, the sensitivity is 33 mV\/decade, and the linear range is 10\u22121\u201310\u22124.56 mol\/L. The R2 and mean square error of the buffer-free sensor in the hydroponic solution are 0.9792 and 0.4936, respectively. In summary, the SPE modified by the Co-nanoparticles is a promising low-cost sensor for on-site and rapid measurement of the phosphate concentration in hydroponic solutions.<\/jats:p>","DOI":"10.3390\/s21010299","type":"journal-article","created":{"date-parts":[[2021,1,5]],"date-time":"2021-01-05T10:35:12Z","timestamp":1609842912000},"page":"299","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["A Co-Nanoparticles Modified Electrode for On-Site and Rapid Phosphate Detection in Hydroponic Solutions"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2294-1237","authenticated-orcid":false,"given":"Feng","family":"Xu","sequence":"first","affiliation":[{"name":"Institute of Intelligent Machines, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, Anhui, China"},{"name":"Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230009, Anhui, China"},{"name":"Department of Mechanical and Nuclear Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA"}]},{"given":"Peng","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Nuclear Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA"}]},{"given":"Shiyuan","family":"Bian","sequence":"additional","affiliation":[{"name":"Institute of Intelligent Machines, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, Anhui, China"},{"name":"Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230009, Anhui, China"}]},{"given":"Yuliang","family":"Wei","sequence":"additional","affiliation":[{"name":"Institute of Intelligent Machines, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, Anhui, China"},{"name":"Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230009, Anhui, China"}]},{"given":"Deyi","family":"Kong","sequence":"additional","affiliation":[{"name":"Institute of Intelligent Machines, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, Anhui, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8531-5279","authenticated-orcid":false,"given":"Huanqin","family":"Wang","sequence":"additional","affiliation":[{"name":"Institute of Intelligent Machines, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, Anhui, China"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Naeem, M., Ansari, A.A., and Gill, S.S. 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