{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,5]],"date-time":"2026-03-05T03:07:14Z","timestamp":1772680034218,"version":"3.50.1"},"reference-count":32,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2019,9,11]],"date-time":"2019-09-11T00:00:00Z","timestamp":1568160000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Thousand-Young-Talent Program of China","award":["NA"],"award-info":[{"award-number":["NA"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The development of new bioelectronic platforms for direct interactions with oral fluid could open up significant opportunities for healthcare monitoring. A tongue depressor is a widely used medical tool that is inserted into the mouth, where it comes into close contact with saliva. Glucose is a typical salivary biomarker. Herein, we report\u2014for the first time\u2014a tongue depressor-based biosensor for the detection of glucose in both phosphate buffer and real human saliva. Carbon nanotubes (CNTs) are attractive electronic materials, with excellent electrochemical properties. The sensor is constructed by printing CNTs and silver\/silver chloride (Ag\/AgCl) to form three electrodes in an electrochemical cell: Working, reference, and counter electrodes. The enzyme glucose oxidase (GOD) is immobilized on the working electrode. The glucose detection performance of the sensor is excellent, with a detection range of 7.3 \u03bcM to 6 mM. The glucose detection time is about 3 min. The discretion between healthy people\u2019s and simulated diabetic patients\u2019 salivary samples is clear and easy to tell. We anticipate that the biosensor could open up new opportunities for the monitoring of salivary biomarkers and advance healthcare applications.<\/jats:p>","DOI":"10.3390\/s19183864","type":"journal-article","created":{"date-parts":[[2019,9,9]],"date-time":"2019-09-09T04:12:40Z","timestamp":1568002360000},"page":"3864","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["A Smart Tongue Depressor-Based Biosensor for Glucose"],"prefix":"10.3390","volume":"19","author":[{"given":"Xiaojin","family":"Luo","sequence":"first","affiliation":[{"name":"College of Engineering, Peking University, Beijing 100871, China"}]},{"given":"Weihua","family":"Shi","sequence":"additional","affiliation":[{"name":"College of Engineering, Peking University, Beijing 100871, China"}]},{"given":"Yiqun","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Engineering, Peking University, Beijing 100871, China"}]},{"given":"Pengju","family":"Sha","sequence":"additional","affiliation":[{"name":"College of Engineering, Peking University, Beijing 100871, China"}]},{"given":"Yanan","family":"Chu","sequence":"additional","affiliation":[{"name":"College of Engineering, Peking University, Beijing 100871, China"}]},{"given":"Yue","family":"Cui","sequence":"additional","affiliation":[{"name":"College of Engineering, Peking University, Beijing 100871, China"}]}],"member":"1968","published-online":{"date-parts":[[2019,9,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"11790","DOI":"10.1021\/acsami.6b15989","article-title":"Magnetic Printing of a Biosensor: Inexpensive Rapid Sensing To Detect Picomolar Amounts of Antigen with Antibody-Functionalized Carbon Nanotubes","volume":"9","author":"Fattah","year":"2017","journal-title":"ACS Appl. 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