{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,22]],"date-time":"2026-06-22T22:34:36Z","timestamp":1782167676483,"version":"3.54.5"},"reference-count":53,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2024,3,15]],"date-time":"2024-03-15T00:00:00Z","timestamp":1710460800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["2411567"],"award-info":[{"award-number":["2411567"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["2143140"],"award-info":[{"award-number":["2143140"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This study aims to develop a microelectrode array-based neural probe that can record dopamine activity with high stability and sensitivity. To mimic the high stability of the gold standard method (carbon fiber electrodes), the microfabricated platinum microelectrode is coated with carbon-based nanomaterials. Carboxyl-functionalized multi-walled carbon nanotubes (COOH-MWCNTs) and carbon quantum dots (CQDs) were selected for this purpose, while a conductive polymer like poly (3-4-ethylene dioxythiophene) (PEDOT) or polypyrrole (PPy) serves as a stable interface between the platinum of the electrode and the carbon-based nanomaterials through a co-electrodeposition process. Based on our comparison between different conducting polymers and the addition of CQD, the CNT\u2013CQD\u2013PPy modified microelectrode outperforms its counterparts: CNT\u2013CQD\u2013PEDOT, CNT\u2013PPy, CNT\u2013PEDOT, and bare Pt microelectrode. The CNT\u2013CQD\u2013PPy modified microelectrode has a higher conductivity, stability, and sensitivity while achieving a remarkable limit of detection (LOD) of 35.20 \u00b1 0.77 nM. Using fast-scan cyclic voltammetry (FSCV), these modified electrodes successfully measured dopamine\u2019s redox peaks while exhibiting consistent and reliable responses over extensive use. This electrode modification not only paves the way for real-time, precise dopamine sensing using microfabricated electrodes but also offers a novel electrochemical sensor for in vivo studies of neural network dynamics and neurological disorders.<\/jats:p>","DOI":"10.3390\/s24061893","type":"journal-article","created":{"date-parts":[[2024,3,15]],"date-time":"2024-03-15T09:32:30Z","timestamp":1710495150000},"page":"1893","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Dopamine Measurement Using Engineered CNT\u2013CQD\u2013Polymer Coatings on Pt Microelectrodes"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9152-2642","authenticated-orcid":false,"given":"Mahdieh","family":"Darroudi","sequence":"first","affiliation":[{"name":"Department of Bioengineering, Erik Johnsson School of Engineering & Computer Science, University of Texas at Dallas, Richardson, TX 75080, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kevin A.","family":"White","sequence":"additional","affiliation":[{"name":"Department of Bioengineering, Erik Johnsson School of Engineering & Computer Science, University of Texas at Dallas, Richardson, TX 75080, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3158-4232","authenticated-orcid":false,"given":"Matthew A.","family":"Crocker","sequence":"additional","affiliation":[{"name":"Department of Bioengineering, Erik Johnsson School of Engineering & Computer Science, University of Texas at Dallas, Richardson, TX 75080, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brian N.","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Bioengineering, Erik Johnsson School of Engineering & Computer Science, University of Texas at Dallas, Richardson, TX 75080, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,3,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2554","DOI":"10.1021\/cr068081q","article-title":"Monitoring Rapid Chemical Communication in the Brain","volume":"108","author":"Robinson","year":"2008","journal-title":"Chem. 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