{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,11]],"date-time":"2026-10-11T15:55:48Z","timestamp":1791734148999,"version":"4.3.4"},"reference-count":48,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,10,25]],"date-time":"2025-10-25T00:00:00Z","timestamp":1761350400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["22504124"],"award-info":[{"award-number":["22504124"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Science and Technology Development Program of Jilin Province","award":["YDZJ202301ZYTS302"],"award-info":[{"award-number":["YDZJ202301ZYTS302"]}]},{"name":"Science and Technology Development Program of Jilin Province","award":["YDZJ202501ZYTS455"],"award-info":[{"award-number":["YDZJ202501ZYTS455"]}]},{"name":"Science and Technology Research Project of Jilin Provincial Department of Education","award":["JJKH20250411KJ"],"award-info":[{"award-number":["JJKH20250411KJ"]}]},{"name":"Doctoral start-up fund of Yanbian University","award":["602024006"],"award-info":[{"award-number":["602024006"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Gels"],"abstract":"<jats:p>Real-time sweat pH monitoring offers a non-invasive window into metabolic status, disease progression, and wound healing. However, current wearable pH sensors struggle to balance high electrochemical sensitivity with mechanical compliance. Here we report a stretchable fiber-integrated pH electrode based on a polyaniline-phytic acid-polyvinyl alcohol (PANI-PA-PVA) hydrogel, which combines mechanical elasticity with enhanced electrochemical performance for continuous sweat sensing. Freeze\u2013thaw crosslinking of the hydrogel forms a porous interpenetrating network, facilitating rapid proton transport and stable coupling with dry-spun elastic gold fibers. This wearable device exhibits an ultra-Nernstian sensitivity of 68.8 mV pH\u22121, ultra-fast equilibrium (&lt;10 s within the sweat-relevant acidic window), long-term drift of 0.0925 mV h\u22121, and high mechanical tolerance (gel stretch recovery up to 165%). The sensor maintains consistent pH responses under bending and tensile strains, yielding sweat pH measurements at the skin surface during running that closely match commercial pH meters (sweat pH range measured in test subjects: 4.2\u20135.0). We further demonstrate real-time wireless readouts by integrating elastic gold and Ag\/AgCl fibers into a three-electrode textile structure. This PANI-PA-PVA hydrogel strategy provides a scalable material platform for robust, high-performance wearable ion sensing and skin diagnostics.<\/jats:p>","DOI":"10.3390\/gels11110853","type":"journal-article","created":{"date-parts":[[2025,10,30]],"date-time":"2025-10-30T03:44:39Z","timestamp":1761795879000},"page":"853","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Development and Electrochemical Performance of a PANI-PA-PVA Hydrogel-Based Flexible pH Fiber Sensor for Real-Time Sweat Monitoring"],"prefix":"10.3390","volume":"11","author":[{"given":"Shiqi","family":"Li","sequence":"first","affiliation":[{"name":"Department of Materials and Chemical Engineering, College of Engineering, Yanbian University, Yanji 133002, China"},{"name":"Laboratory of Catalysis for Energy and Resources, College of Sciences, Yanbian University, Yanji 133002, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6994-1317","authenticated-orcid":false,"given":"Chao","family":"Sun","sequence":"additional","affiliation":[{"name":"Department of Physics, Jilin University, Changchun 130012, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Meihui","family":"Gao","sequence":"additional","affiliation":[{"name":"Laboratory of Catalysis for Energy and Resources, College of Sciences, Yanbian University, Yanji 133002, China"},{"name":"Department of Chemistry, College of Science, Yanbian University, Yanji 133002, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haiyan","family":"Ma","sequence":"additional","affiliation":[{"name":"Laboratory of Catalysis for Energy and Resources, College of Sciences, Yanbian University, Yanji 133002, China"},{"name":"Department of Chemistry, College of Science, Yanbian University, Yanji 133002, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Longbin","family":"Xu","sequence":"additional","affiliation":[{"name":"Department of Materials and Chemical Engineering, College of Engineering, Yanbian University, Yanji 133002, China"},{"name":"Laboratory of Catalysis for Energy and Resources, College of Sciences, Yanbian University, Yanji 133002, China"},{"name":"Department of Chemistry, College of Science, Yanbian University, Yanji 133002, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xinyu","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Materials and Chemical Engineering, College of Engineering, Yanbian University, Yanji 133002, China"},{"name":"Department of Chemistry, College of Science, Yanbian University, Yanji 133002, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1465","DOI":"10.1039\/C7CS00730B","article-title":"Wearable and flexible electronics for continuous molecular monitoring","volume":"48","author":"Yang","year":"2019","journal-title":"Chem. 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Proceedings of the 2021 IEEE Sensors, Sydney, Australia.","DOI":"10.1109\/SENSORS47087.2021.9639597"}],"container-title":["Gels"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2310-2861\/11\/11\/853\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,30]],"date-time":"2025-10-30T05:19:33Z","timestamp":1761801573000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2310-2861\/11\/11\/853"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,10,25]]},"references-count":48,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2025,11]]}},"alternative-id":["gels11110853"],"URL":"https:\/\/doi.org\/10.3390\/gels11110853","relation":{},"ISSN":["2310-2861"],"issn-type":[{"value":"2310-2861","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,10,25]]}}}