{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T14:47:50Z","timestamp":1784818070816,"version":"3.55.0"},"reference-count":57,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,1,11]],"date-time":"2025-01-11T00:00:00Z","timestamp":1736553600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["52003212"],"award-info":[{"award-number":["52003212"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Gels"],"abstract":"<jats:p>Protein-based hydrogels with stretchability and conductivity have potential applications in wearable electronic devices. However, the development of protein-based biocomposite hydrogels is still limited. In this work, we used natural ferritin to develop a PVA\/ferritin biocomposite hydrogel by a repetitive freeze\u2013thaw method. In this biocomposite hydrogel, ferritin, as a nano spring, forms a hydrogen bond with the PVA networks, which reduces the crystallinity of PVA and significantly improves the stretchability of the hydrogel. The fracture strain of the PVA\/ferritin hydrogel is 203%, and the fracture stress is 112.2 kPa. The fracture toughness of the PVA\/ferritin hydrogel is significantly enhanced to 147.03 kJ\/m3, more than 3 times that of the PVA hydrogel (39.17 kJ\/m3). In addition, the free residues and iron ions of ferritin endow the biocomposite hydrogel with enhanced ionic conductivity (0.15 S\/m). The strain sensor constructed from this hydrogel shows good sensitivity (gauge factor = 1.7 at 150% strain), accurate real-time resistance response, and good long cyclic working stability when used for joint motion monitoring. The results indicate that a PVA\/ferritin biocomposite hydrogel prepared by a facile method has enhanced stretchability and conductivity for flexible strain sensors. This work develops a new method for the preparation of protein-based hydrogels for wearable electronic devices.<\/jats:p>","DOI":"10.3390\/gels11010059","type":"journal-article","created":{"date-parts":[[2025,1,13]],"date-time":"2025-01-13T07:40:08Z","timestamp":1736754008000},"page":"59","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Biocomposite Polyvinyl Alcohol\/Ferritin Hydrogels with Enhanced Stretchability and Conductivity for Flexible Strain Sensors"],"prefix":"10.3390","volume":"11","author":[{"given":"Qiang","family":"Fu","sequence":"first","affiliation":[{"name":"China Shipbuilding Industry Corporation, Research Institute 712, Wuhan 430064, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Junxiao","family":"Tang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China"},{"name":"Hubei Longzhong Laboratory, Xiangyang 441022, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Weimin","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China"},{"name":"Hubei Longzhong Laboratory, Xiangyang 441022, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rongjie","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China"},{"name":"Hubei Longzhong Laboratory, Xiangyang 441022, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7642","DOI":"10.1021\/acs.chemrev.0c00345","article-title":"Hydrogels and hydrogel-derived materials for energy and water sustainability","volume":"120","author":"Guo","year":"2020","journal-title":"Chem. 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