{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T18:48:06Z","timestamp":1785523686939,"version":"3.56.0"},"reference-count":38,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T00:00:00Z","timestamp":1776297600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key R&D Program of China","doi-asserted-by":"crossref","award":["2023YFB4706200"],"award-info":[{"award-number":["2023YFB4706200"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100003512","name":"State Administration of Foreign Experts Affairs","doi-asserted-by":"publisher","award":["H20240225"],"award-info":[{"award-number":["H20240225"]}],"id":[{"id":"10.13039\/501100003512","id-type":"DOI","asserted-by":"publisher"}]},{"award":["H20240225"],"award-info":[{"award-number":["H20240225"]}],"id":[{"id":"https:\/\/ror.org\/055gka453","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Chinese Academy of Sciences International Talent Plan (PIFI) Project","award":["2024VBB0010"],"award-info":[{"award-number":["2024VBB0010"]}]},{"name":"Pilot Projects for Fundamental Research in Suzhou","award":["SSD2023014"],"award-info":[{"award-number":["SSD2023014"]}]},{"name":"Science and Technology Development Plan Project of Jilin Province","award":["20240305049YY"],"award-info":[{"award-number":["20240305049YY"]}]},{"name":"Natural Science Foundation Project of Shandong Province","award":["ZR2022QH214"],"award-info":[{"award-number":["ZR2022QH214"]}]},{"name":"Natural Science Foundation Project of Chongqing","award":["2024NSCQ-MSX0007"],"award-info":[{"award-number":["2024NSCQ-MSX0007"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>Precise monitoring of forearm muscle groups is crucial for decoding motor intentions in human\u2013machine interfaces (HMIs) and rehabilitation. However, traditional surface electromyography (sEMG) electrodes face significant challenges in densely packed muscle regions with large skin deformations, leading to severe signal crosstalk and unstable contact. Here, we report a flexible, low-cost 16-channel copper electrode array system designed for the high-density monitoring of multiple forearm muscle activities. Through a facile fabrication process, rigid copper is transformed into a conformable sensing interface. The optimized serpentine interconnects endow the array with excellent stretchability and effectively isolate motion-induced stress, ensuring high-quality signal acquisition under complex deformations. The high-density 2 \u00d7 8 array enables the spatiotemporal mapping of distributed flexor and extensor muscle groups. Integrated with a customized wireless data acquisition system, the array successfully demonstrates real-time, multi-channel sEMG monitoring of various hand movements (e.g., fist clenching, wrist flexion\/extension), clearly revealing specific muscle activation patterns. This low-cost, high-performance flexible sensor array provides a highly promising tool for complex gesture decoding, electromyographic imaging, and next-generation wearable HMIs.<\/jats:p>","DOI":"10.3390\/bioengineering13040467","type":"journal-article","created":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T14:05:36Z","timestamp":1776348336000},"page":"467","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["A Flexible Copper Electrode Array for High-Density Surface Electromyography"],"prefix":"10.3390","volume":"13","author":[{"given":"Chaoxin","family":"Li","sequence":"first","affiliation":[{"name":"Division of Life Sciences and Medicine, School of Biomedical Engineering (Suzhou), University of Science and Technology of China, Hefei 230022, China"},{"name":"Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chenghong","family":"Lu","sequence":"additional","affiliation":[{"name":"Division of Life Sciences and Medicine, School of Biomedical Engineering (Suzhou), University of Science and Technology of China, Hefei 230022, China"},{"name":"Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiuqiang","family":"Li","sequence":"additional","affiliation":[{"name":"Division of Life Sciences and Medicine, School of Biomedical Engineering (Suzhou), University of Science and Technology of China, Hefei 230022, China"},{"name":"Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2071-6869","authenticated-orcid":false,"given":"Kai","family":"Guo","sequence":"additional","affiliation":[{"name":"Division of Life Sciences and Medicine, School of Biomedical Engineering (Suzhou), University of Science and Technology of China, Hefei 230022, China"},{"name":"Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China"},{"name":"Jinan Guoke Medical Technology Development Co., Ltd., Jinan 250101, China"},{"name":"Chongqing Guoke Medical Innovation Technology Development Co., Ltd., Chongqing 404100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Merletti, R., and Farina, D. 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