{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,17]],"date-time":"2026-02-17T13:27:41Z","timestamp":1771334861055,"version":"3.50.1"},"reference-count":20,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2013,12,4]],"date-time":"2013-12-04T00:00:00Z","timestamp":1386115200000},"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>We report fabrication of a microneedle-based three-electrode integrated electrochemical sensor and in-vitro characterization of this sensor for glucose sensing applications. A piece of silicon was sequentially dry and wet etched to form a 15 \u00d7 15 array of tall (approximately 380 \u00b5m) sharp silicon microneedles. Iron catalyst was deposited through a SU-8 shadow mask to form the working electrode and counter electrode. A multi-walled carbon nanotube forest was grown directly on the silicon microneedle array and platinum nano-particles were electrodeposited. Silver was deposited on the Si microneedle array through another shadow mask and chlorinated to form a Ag\/AgCl reference electrode. The 3-electrode electrochemical sensor was tested for various glucose concentrations in the range of 3~20 mM in 0.01 M phosphate buffered saline (PBS) solution. The sensor\u2019s amperometric response to the glucose concentration is linear and its sensitivity was found to be 17.73 \u00b1 3 \u03bcA\/mM-cm2. This microneedle-based sensor has a potential to be used for painless diabetes testing applications.<\/jats:p>","DOI":"10.3390\/s131216672","type":"journal-article","created":{"date-parts":[[2013,12,4]],"date-time":"2013-12-04T12:02:38Z","timestamp":1386158558000},"page":"16672-16681","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":78,"title":["Fabrication of a Microneedle\/CNT Hierarchical Micro\/Nano Surface Electrochemical Sensor and Its In-Vitro Glucose Sensing Characterization"],"prefix":"10.3390","volume":"13","author":[{"given":"Youngsam","family":"Yoon","sequence":"first","affiliation":[{"name":"Department of Electrical Engineering, the University of Texas at Dallas, 800 W. Campbell Rd., Richardson, TX 75080, USA"}]},{"given":"Gil","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, the University of Texas at Dallas, 800 W. Campbell Rd., Richardson, TX 75080, USA"}]},{"given":"Koangki","family":"Yoo","sequence":"additional","affiliation":[{"name":"Department of Information and Communication Engineering, Hanbat National University, 125 Dongseodaero, Yuseong-Gu, Daejeon 305-719, Korea"}]},{"given":"Jeong-Bong","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, the University of Texas at Dallas, 800 W. Campbell Rd., Richardson, TX 75080, USA"}]}],"member":"1968","published-online":{"date-parts":[[2013,12,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1047","DOI":"10.2337\/diacare.27.5.1047","article-title":"Global prevalence of diabetes","volume":"27","author":"Wild","year":"2004","journal-title":"Diabetes Care"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1089\/15209150252924058","article-title":"Alternate site glucose testing: A crossover design","volume":"4","author":"Bennion","year":"2004","journal-title":"Diabetes Technol. Ther."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2353","DOI":"10.1373\/clinchem.2004.039701","article-title":"Photonic crystal glucose-sensing material for noninvasive monitoring of glucose in tear fluid","volume":"50","author":"Alexeev","year":"2004","journal-title":"Clin. 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