{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T21:26:45Z","timestamp":1782941205996,"version":"3.54.5"},"reference-count":33,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2020,10,26]],"date-time":"2020-10-26T00:00:00Z","timestamp":1603670400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["NRF-2019R1F1A1063034"],"award-info":[{"award-number":["NRF-2019R1F1A1063034"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["10Z20130000004"],"award-info":[{"award-number":["10Z20130000004"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"name":"The Ministry of Oceans and Fisheries, Korea","award":["20150242"],"award-info":[{"award-number":["20150242"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A simple one-step electrochemical deposition\/activation of graphitic carbon nitride (g-C3N4) is highly desired for sensor configurations and remains a great challenge. Herein, we attempt an electrochemical route to exfoliate the g-C3N4 nanosheets in an aqueous solution of pH 7.0 for constructing a sensor, which is highly sensitive for the detection of serotonin (5-HT). The significance of our design is to exfoliate the g-C3N4 nanosheets, a strong electrocatalyst for 5-HT detection. Investigations regarding the effect of neutral pH (pH 7.0) on the bulk g-C3N4 and g-C3N4 nanosheets, physical characterization, and electrochemical studies were extensively carried out. We demonstrate that the g-C3N4 nanosheets have a significant electrocatalytic effect for the 5-HT detection in a dynamic linear range from 500 pM to 1000 nM (R2 = 0.999). The limit of detection and sensitivity of the designed 5-HT sensor was calculated to be 150 pM and 1.03 \u00b5A \u00b5M\u22121 cm\u22122, respectively. The proposed sensor has great advantages such as high sensitivity, good selectivity, reproducibility, and stability. The constructed g-C3N4 nanosheets-based sensor platform opens new feasibilities for the determination of 5-HT even at the picomolar\/nanomolar concentration range.<\/jats:p>","DOI":"10.3390\/s20216083","type":"journal-article","created":{"date-parts":[[2020,10,26]],"date-time":"2020-10-26T10:38:35Z","timestamp":1603708715000},"page":"6083","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Cost-Effective Electrochemical Activation of Graphitic Carbon Nitride on the Glassy Carbon Electrode Surface for Selective Determination of Serotonin"],"prefix":"10.3390","volume":"20","author":[{"given":"Vijayaraj","family":"Kathiresan","sequence":"first","affiliation":[{"name":"Graduate Department of Chemical Materials, Pusan National University, Busan 46241, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thenmozhi","family":"Rajarathinam","sequence":"additional","affiliation":[{"name":"Department of Cogno-Mechatronics Engineering, Department of Optics and Mechatronics Engineering, College of Nanoscience and Nanotechnology, Pusan National University, Busan 46241, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Seulah","family":"Lee","sequence":"additional","affiliation":[{"name":"College of Pharmacy, Pusan National University, Busan 46241, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Suhkmann","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Pusan National University, Busan 46241, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3203-2130","authenticated-orcid":false,"given":"Jaewon","family":"Lee","sequence":"additional","affiliation":[{"name":"College of Pharmacy, Pusan National University, Busan 46241, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9005-5990","authenticated-orcid":false,"given":"Dinakaran","family":"Thirumalai","sequence":"additional","affiliation":[{"name":"Department of Cogno-Mechatronics Engineering, Department of Optics and Mechatronics Engineering, College of Nanoscience and Nanotechnology, Pusan National University, Busan 46241, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2333-9424","authenticated-orcid":false,"given":"Seung-Cheol","family":"Chang","sequence":"additional","affiliation":[{"name":"Department of Cogno-Mechatronics Engineering, Department of Optics and Mechatronics Engineering, College of Nanoscience and Nanotechnology, Pusan National University, Busan 46241, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"186","DOI":"10.1016\/j.bios.2017.05.014","article-title":"A novel sensitive sensor for serotonin based on high-quality of AuAg nanoalloy encapsulated graphene electrocatalyst","volume":"96","author":"Thanh","year":"2017","journal-title":"Biosens. 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