{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,14]],"date-time":"2026-03-14T08:19:30Z","timestamp":1773476370316,"version":"3.50.1"},"reference-count":38,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2011,6,27]],"date-time":"2011-06-27T00:00:00Z","timestamp":1309132800000},"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>Zinc oxide field effect transistors (ZnO-FET), covalently functionalized with single stranded DNA aptamers, provide a highly selective platform for label-free small molecule sensing. The nanostructured surface morphology of ZnO provides high sensitivity and room temperature deposition allows for a wide array of substrate types. Herein we demonstrate the selective detection of riboflavin down to the pM level in aqueous solution using the negative electrical current response of the ZnO-FET by covalently attaching a riboflavin binding aptamer to the surface. The response of the biofunctionalized ZnO-FET was tuned by attaching a redox tag (ferrocene) to the 3\u2019 terminus of the aptamer, resulting in positive current modulation upon exposure to riboflavin down to pM levels.<\/jats:p>","DOI":"10.3390\/s110706645","type":"journal-article","created":{"date-parts":[[2011,6,27]],"date-time":"2011-06-27T22:44:03Z","timestamp":1309214643000},"page":"6645-6655","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":47,"title":["Biofunctionalized Zinc Oxide Field Effect Transistors for Selective Sensing of Riboflavin with Current Modulation"],"prefix":"10.3390","volume":"11","author":[{"given":"Joshua A.","family":"Hagen","sequence":"first","affiliation":[{"name":"711th Human Performance Wing, Human Effectiveness Directorate, Air Force Research Labs, Wright Patterson Air Force Base, OH 45433, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sang N.","family":"Kim","sequence":"additional","affiliation":[{"name":"Materials and Manufacturing Directorate, Air Force Research Labs, Wright Patterson Air Force Base, OH 45433, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Burhan","family":"Bayraktaroglu","sequence":"additional","affiliation":[{"name":"Sensors Directorate, Air Force Research Labs, Wright Patterson Air Force Base, OH 45433, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kevin","family":"Leedy","sequence":"additional","affiliation":[{"name":"Sensors Directorate, Air Force Research Labs, Wright Patterson Air Force Base, OH 45433, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jorge L.","family":"Ch\u00e1vez","sequence":"additional","affiliation":[{"name":"711th Human Performance Wing, Human Effectiveness Directorate, Air Force Research Labs, Wright Patterson Air Force Base, OH 45433, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nancy","family":"Kelley-Loughnane","sequence":"additional","affiliation":[{"name":"711th Human Performance Wing, Human Effectiveness Directorate, Air Force Research Labs, Wright Patterson Air Force Base, OH 45433, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rajesh R.","family":"Naik","sequence":"additional","affiliation":[{"name":"Materials and Manufacturing Directorate, Air Force Research Labs, Wright Patterson Air Force Base, OH 45433, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Morley O.","family":"Stone","sequence":"additional","affiliation":[{"name":"711th Human Performance Wing, Human Effectiveness Directorate, Air Force Research Labs, Wright Patterson Air Force Base, OH 45433, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2011,6,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"877","DOI":"10.1021\/nl034061h","article-title":"Alcohol vapor sensors based on single-walled carbon nanotube field effect transistors","volume":"3","author":"Someya","year":"2003","journal-title":"Nano Lett"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1421","DOI":"10.1021\/nl0346833","article-title":"Interaction of aromatic compounds with carbon nanotubes: Correlation to the Hammett parameter of the substituent and measured carbon nanotube FET response","volume":"3","author":"Star","year":"2003","journal-title":"Nano Lett"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"158","DOI":"10.1016\/j.snb.2005.04.026","article-title":"A study of fast response characteristics for hydrogen sensing with platinum FET sensor","volume":"114","author":"Tsukada","year":"2006","journal-title":"Sens. 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