{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,19]],"date-time":"2026-10-19T14:02:11Z","timestamp":1792418531512,"version":"4.5.0"},"reference-count":32,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,5,21]],"date-time":"2025-05-21T00:00:00Z","timestamp":1747785600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Bioeng. Biotechnol."],"abstract":"<jats:sec><jats:title>Introduction<\/jats:title><jats:p>Modern wearable electronics demand materials that are simultaneously stretchable, conductive, and environmentally robust. Hydrogels meet some of these requirements but dehydrate or freeze easily. To overcome these limitations, we prepared a poly-ionic-liquid (PIL) ionogel that integrates high elasticity with stable ionic conductivity, aiming to enable reliable, skin-compatible strain and biopotential sensing.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>1-Vinyl-3-butyl-imidazolium hexafluorophosphate and 1-butyl-3-methyl-imidazolium hexafluorophosphate were mixed at optimized mass ratios, followed by N,N\u2019-methylenebis-acrylamide (cross-linker) and Irgacure-2959 (photoinitiator). The homogeneous precursor was UV-cured for 6 min to obtain a PIL ionogel (PIL-1 \u2013 PIL-4 series). Structural, thermal, mechanical, rheological, adhesive, and electrical characteristics were analysed by FT-IR, SEM, TGA\/DSC, uniaxial tensile testing, rheometry, 90\u00b0 peel tests, and real-time resistance measurements. Applications were evaluated by attaching the gel to human joints and by recording EMG\/ECG signals.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>The UV one-step process yielded a dense multi-cross-linked network that combined covalent and ionic interactions. The optimised sample (PIL-2) showed a fracture stress of \u223c390 kPa with 320% elongation, sustaining a 500 g load without failure. It retained mass and softness after 30 days and adhered strongly (up to 90\u00b0 peel strength &amp;gt;4 N) to glass, metals, and skin\u2014even underwater. Electrical tests gave a gauge factor of 1.94 (0\u2013100%), 3.98 (100\u2013200%), and 4.04 (200\u2013320%), with 400 ms response and 500 ms recovery. The gel monitored finger (30\u00b0\/90\u00b0), wrist, and elbow motions reproducibly, functioned as a bioelectrode capturing stable EMG\/ECG with clear PQRST waves, and reliably transmitted Morse code via hand gestures.<\/jats:p><\/jats:sec><jats:sec><jats:title>Discussion<\/jats:title><jats:p>The solvent-free PIL ionogel couples mechanical toughness, wide-range elasticity, and stable ionic pathways, outperforming water-rich hydrogels in thermal\/long-term stability. Its strong, humidity-tolerant adhesion eliminates extra fixatives, while rapid, high-gain strain transduction and low-impedance skin contact enable multimodal biosensing. These attributes position the material for next-generation flexible electronics, real-time health monitoring, and gesture-based human-machine interfaces.<\/jats:p><\/jats:sec>","DOI":"10.3389\/fbioe.2025.1610197","type":"journal-article","created":{"date-parts":[[2025,5,21]],"date-time":"2025-05-21T05:24:54Z","timestamp":1747805094000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":4,"title":["Flexible wearable biosensors from poly (ionic liquid) for real-time signal monitoring"],"prefix":"10.3389","volume":"13","author":[{"given":"Yao","family":"Liu","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Siyu","family":"Han","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Panpan","family":"Gu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bai","family":"Wang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shiyan","family":"Tian","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoxu","family":"Xu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chunmei","family":"Yang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shujun","family":"Liu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jianshe","family":"Hu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2025,5,21]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1151","DOI":"10.1080\/02678292.2023.2188615","article-title":"Ionic liquid crystal elastomers for actuators, sensors, and organic transistors","volume":"50","author":"Alyami","year":"2023","journal-title":"Liq. 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