{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T08:56:21Z","timestamp":1777366581690,"version":"3.51.4"},"reference-count":31,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2017,8,8]],"date-time":"2017-08-08T00:00:00Z","timestamp":1502150400000},"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>Temperature-dependent zeolite synthesis has revealed a unique surface morphology, surface area and pore size which influence the immobilization of urease on gold electrode supports for biosensor fabrication. XRD characterization has identified zeolite X (Na) at all crystallization temperatures tested. However, N2 adsorption and desorption results showed a pore size and pore volume of zeolite X (Na) 60 \u00b0C, zeolite X (Na) 70 \u00b0C and zeolite X (Na) 90 \u00b0C to range from 1.92 nm to 2.45 nm and 0.012 cm3\/g to 0.061 cm3\/g, respectively, with no significant differences. The specific surface area of zeolite X (Na) at 60, 70 and 90 \u00b0C was 64 m2\/g, 67 m2\/g and 113 m2\/g, respectively. The pore size, specific surface area and pore volumes of zeolite X (Na) 80 \u00b0C and zeolite X (Na) 100 \u00b0C were dramatically increased to 4.21 nm, 295 m2\/g, 0.762 cm3\/g and 4.92 nm, 389 m2\/g, 0.837 cm3\/g, in that order. The analytical performance of adsorbed urease on zeolite X (Na) surface was also investigated using cyclic voltammetry measurements, and the results showed distinct cathodic and anodic peaks by zeolite X (Na) 80 \u00b0C and zeolite X (Na) 100 \u00b0C. These zeolites\u2019 molar conductance was measured as a function of urea concentration and gave an average polynomial regression fit of 0.948. The findings in this study suggest that certain physicochemical properties, such as crystallization temperature and pH, are critical parameters for improving the morphological properties of zeolites synthesized from natural sources for various biomedical applications.<\/jats:p>","DOI":"10.3390\/s17081831","type":"journal-article","created":{"date-parts":[[2017,8,8]],"date-time":"2017-08-08T10:28:08Z","timestamp":1502188088000},"page":"1831","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Investigating the Influence of Temperature on the Kaolinite-Base Synthesis of Zeolite and Urease Immobilization for the Potential Fabrication of Electrochemical Urea Biosensors"],"prefix":"10.3390","volume":"17","author":[{"given":"David","family":"Anderson","sequence":"first","affiliation":[{"name":"Department of Biomedical Engineering, University of Ghana, P. O. Box LG 25, Legon, Accra, Ghana"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Srinivasan","family":"Balapangu","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, University of Ghana, P. O. Box LG 25, Legon, Accra, Ghana"},{"name":"West African Centre for Cell Biology of Infectious Pathogens, University of Ghana, P. O. Box LG 25, Legon, Accra, Ghana"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Heidimarie N. A.","family":"Fleischer","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, University of Ghana, P. O. Box LG 25, Legon, Accra, Ghana"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ruth A.","family":"Viade","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, University of Ghana, P. O. Box LG 25, Legon, Accra, Ghana"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2414-6197","authenticated-orcid":false,"given":"Francis D.","family":"Krampa","sequence":"additional","affiliation":[{"name":"West African Centre for Cell Biology of Infectious Pathogens, University of Ghana, P. O. Box LG 25, Legon, Accra, Ghana"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Prosper","family":"Kanyong","sequence":"additional","affiliation":[{"name":"School of Engineering, Ulster University, Jordanstown BT37 0QB, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5011-8686","authenticated-orcid":false,"given":"Gordon A.","family":"Awandare","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Cell and Molecular Biology, University of Ghana, P. O. Box LG 25, Legon, Accra, Ghana"},{"name":"West African Centre for Cell Biology of Infectious Pathogens, University of Ghana, P. O. Box LG 25, Legon, Accra, Ghana"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elvis K.","family":"Tiburu","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, University of Ghana, P. O. Box LG 25, Legon, Accra, Ghana"},{"name":"West African Centre for Cell Biology of Infectious Pathogens, University of Ghana, P. O. Box LG 25, Legon, Accra, Ghana"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,8,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3965","DOI":"10.1021\/ac060637m","article-title":"Electrochemical Seonsors","volume":"78","author":"Bakker","year":"2006","journal-title":"Anal. 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