{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,7]],"date-time":"2026-03-07T01:19:21Z","timestamp":1772846361046,"version":"3.50.1"},"reference-count":38,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2012,3,1]],"date-time":"2012-03-01T00:00:00Z","timestamp":1330560000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In the present work zinc oxide nanoflakes (ZnO-NF) structures with a wall thickness around 50 to 100 nm were synthesized on a gold coated glass substrate using a low temperature hydrothermal method. The enzyme uricase was electrostatically immobilized in conjunction with Nafion membrane on the surface of well oriented ZnO-NFs, resulting in a sensitive, selective, stable and reproducible uric acid sensor. The electrochemical response of the ZnO-NF-based sensor vs. a Ag\/AgCl reference electrode was found to be linear over a relatively wide logarithmic concentration range (500 nM to 1.5 mM). In addition, the ZnO-NF structures demonstrate vast surface area that allow high enzyme loading which results provided a higher sensitivity. The proposed ZnO-NF array-based sensor exhibited a high sensitivity of ~66 mV\/ decade in test electrolyte solutions of uric acid, with fast response time. The sensor response was unaffected by normal concentrations of common interferents such as ascorbic acid, glucose, and urea.<\/jats:p>","DOI":"10.3390\/s120302787","type":"journal-article","created":{"date-parts":[[2012,3,1]],"date-time":"2012-03-01T11:01:53Z","timestamp":1330599713000},"page":"2787-2797","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":69,"title":["A Potentiometric Indirect Uric Acid Sensor Based on ZnO Nanoflakes and Immobilized Uricase"],"prefix":"10.3390","volume":"12","author":[{"given":"Syed M. Usman","family":"Ali","sequence":"first","affiliation":[{"name":"Department of Science and Technology, Link\u00f6ping University, Campus Norrk\u00f6ping, Norrkoping SE-60174, Sweden"},{"name":"Department of Electronic Engineering, NED University of Engineering and Technology, Karachi 75270, Pakistan"}]},{"given":"Zafar Hussain","family":"Ibupoto","sequence":"additional","affiliation":[{"name":"Department of Science and Technology, Link\u00f6ping University, Campus Norrk\u00f6ping, Norrkoping SE-60174, Sweden"}]},{"given":"Muhammad","family":"Kashif","sequence":"additional","affiliation":[{"name":"Nano Biochip Research Group, Institute of Nano Electronic Engineering (INEE), University Malaysia Perlis, Kangar, Perlis 01000, Malaysia"}]},{"given":"Uda","family":"Hashim","sequence":"additional","affiliation":[{"name":"Nano Biochip Research Group, Institute of Nano Electronic Engineering (INEE), University Malaysia Perlis, Kangar, Perlis 01000, Malaysia"}]},{"given":"Magnus","family":"Willander","sequence":"additional","affiliation":[{"name":"Department of Science and Technology, Link\u00f6ping University, Campus Norrk\u00f6ping, Norrkoping SE-60174, Sweden"}]}],"member":"1968","published-online":{"date-parts":[[2012,3,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"73","DOI":"10.1016\/S0039-9140(03)00239-X","article-title":"A biosensor based on urate oxidase-peroxidase coupled enzyme system for uric acid determination in urine","volume":"61","author":"Akyilmaz","year":"2003","journal-title":"Talanta"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"369","DOI":"10.1185\/030079904125002982","article-title":"Uric acid: Role in cardiovascular disease and effects of losartan","volume":"20","author":"Alderman","year":"2004","journal-title":"Curr. 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