{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T14:42:45Z","timestamp":1768315365744,"version":"3.49.0"},"reference-count":34,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,7,27]],"date-time":"2023-07-27T00:00:00Z","timestamp":1690416000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Gels"],"abstract":"<jats:p>In the present work, a biocatalytic glucose optical sensor produced by immobilizing glucose oxidase (GOD) as a recognition molecule over a PMMA (polymethylmethacrylate) optical fiber is introduced. An enzymatic encapsulation process was carried out using the sol\u2013gel method, depositing a TEOS-based coating by immersion at the end of an optical fiber; the biosensor was characterized using different glucose levels. Finally, the best way to encapsulate the enzyme and prevent it from degrading is to perform the process at room temperature, and later implement the deposition of the coating on the fiber. The drying process was optimal below 8 \u00b0C.<\/jats:p>","DOI":"10.3390\/gels9080608","type":"journal-article","created":{"date-parts":[[2023,7,28]],"date-time":"2023-07-28T02:10:45Z","timestamp":1690510245000},"page":"608","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Glucose Sensor Using Sol\u2013Gel Coating Layer Deposited on PMMA Optical Fiber: An Enzyme Activity Measurement System"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6834-3163","authenticated-orcid":false,"given":"Jorge-A.","family":"Ortega-Contreras","sequence":"first","affiliation":[{"name":"Department of Electrical Engineering, DICIS, Universidad de Guanajuato, Salamanca 36787, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Edgar","family":"Alvarado-M\u00e9ndez","sequence":"additional","affiliation":[{"name":"Department of Electronics Engineering, DICIS, Universidad de Guanajuato, Salamanca 36787, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-1946-6536","authenticated-orcid":false,"given":"Guillermo","family":"Almanza-Rodr\u00edguez","sequence":"additional","affiliation":[{"name":"Department of Biochemical Engineering, Tecnol\u00f3gico Nacional de M\u00e9xico, Celaya 38010, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-1431-9522","authenticated-orcid":false,"given":"Mar\u00eda del Carmen","family":"Hern\u00e1ndez","sequence":"additional","affiliation":[{"name":"Department of Biochemical Engineering, Tecnol\u00f3gico Nacional de M\u00e9xico, Celaya 38010, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6513-696X","authenticated-orcid":false,"given":"Luis","family":"Celaya-Garc\u00eda","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, DICIS, Universidad de Guanajuato, Salamanca 36787, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,27]]},"reference":[{"key":"ref_1","unstructured":"McNaught, A.D., and Wilkinson, A. 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