{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T08:50:13Z","timestamp":1778575813275,"version":"3.51.4"},"reference-count":40,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2020,4,26]],"date-time":"2020-04-26T00:00:00Z","timestamp":1587859200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004663","name":"Ministry of Science and Technology, Taiwan","doi-asserted-by":"publisher","award":["105-2923-E-194-003-MY3, 106-2112-M-194-002, and 108-2823-8-194-002"],"award-info":[{"award-number":["105-2923-E-194-003-MY3, 106-2112-M-194-002, and 108-2823-8-194-002"]}],"id":[{"id":"10.13039\/501100004663","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A highly sensitive photoelectrochemical (PEC) biosensor without external bias was developed in this study. The biosensor was configured with a p-Cu2O and n-ZnO heterostructure. Hexamethylenetetramine (HMTA) and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) was used to improve the crystal structure of Cu2O and ZnO and reduce the defects in the Cu2O\/ZnO interface. This fabrication method provided the highly crystallized Cu2O\/ZnO structure with excellent electrical property and photoresponse in visible light. The structure was applied to a biosensor for detecting two different cancerous levels of esophageal cells, namely, OE21 and OE21-1, with a high gain in photocurrent (5.8 and 6.2 times, respectively) and a low detection limit (3000 cells in 50 \u03bcL). We believe that such a p-n heterojunction PEC biosensor could advance biosensor development and provide a promising candidate for biomedical applications.<\/jats:p>","DOI":"10.3390\/s20092455","type":"journal-article","created":{"date-parts":[[2020,4,28]],"date-time":"2020-04-28T10:30:58Z","timestamp":1588069858000},"page":"2455","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["Cu2O\/PEDOT:PSS\/ZnO Nanocomposite Material Biosensor for Esophageal Cancer Detection"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4681-2939","authenticated-orcid":false,"given":"Kuang-Wen","family":"Tseng","sequence":"first","affiliation":[{"name":"Department of Medicine, Mackay Medical College, 46, Sec. 3, Zhongzheng Rd., Sanzhi Dist., New Taipei 25245, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yu-Ping","family":"Hsiao","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Chung Shan Medical University and Chung Shan Medical University Hospital, No.110, Sec. 1, Jianguo N. Rd., South Dist., Taichung City 40201, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5558-5817","authenticated-orcid":false,"given":"Chun-Ping","family":"Jen","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering and Advanced Institute of Manufacturing with High Tech Innovations, National Chung Cheng University, 168, University Rd., Min Hsiung, Chia Yi 62102, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tsung-Shun","family":"Chang","sequence":"additional","affiliation":[{"name":"Department of Otolaryngology, Kaohsiung Armed Forced General Hospital, 2, Zhongzheng 1st. Rd., Lingya District, Kaohsiung City 80284, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4107-2062","authenticated-orcid":false,"given":"Hsiang-Chen","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering and Advanced Institute of Manufacturing with High Tech Innovations, National Chung Cheng University, 168, University Rd., Min Hsiung, Chia Yi 62102, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,4,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"33","DOI":"10.3322\/canjclin.49.1.33","article-title":"Global cancer statistics","volume":"49","author":"Parkin","year":"1999","journal-title":"CA A Cancer J. 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