Wang Bingfang, Lv Ailin, Wu Haofan, Guo Bihan, Lu Yuhan, Chang Zhiqiang, Wu Yuqing, Li Xiang, Yang Qiuyu, Nie Jianfang, Wei Jing, Ren Qinjuan, Ji Daizong, Zhang Ya, Rotenberg Menahem Y, Fang Yin
Research Center for Translational Medicine, Medical Innovation Center and State Key Laboratory of Cardiology, Shanghai East Hospital; The Institute for Biomedical Engineering & Nano Science, Tongji University School of Medicine, Shanghai 200120, China.
Shanghai Research Institute for Intelligent Autonomous Systems, Shanghai 201210, China.
ACS Nano. 2025 Mar 4;19(8):8176-8188. doi: 10.1021/acsnano.4c17062. Epub 2025 Feb 17.
Cardiovascular disease (CAD) is a major global public health issue, with mortality rates being significantly impacted by cold temperatures. Stable and reliable electrocardiogram (ECG) monitoring in cold environments is crucial for early detection and treatment of CAD. However, existing skin sensor struggle to balance freeze resistance, breathability, flexibility, conductivity and adhesion at cold temperatures. Here, we introduce a solvent cross-linking strategy and an in situ transfer method to prepare ultrathin bioionic gels, featuring a freezing point below -80 °C and a thickness of only 12.6 μm. The strong and abundant interactions between the ionic liquid solvent and the zwitterionic polymer effectively suppress low-temperature crystallization, forming a toughened and highly adhesive network structure. This network enables the in situ formation of an ultrathin morphology, which can be seamlessly transferred onto various substrates. Furthermore, the solvent-cross-linked network maintains a large interpolymer chain spacing, facilitating rapid ion transport pathways. Even at subzero temperatures, the gel maintains its multifunctionality, demonstrating tissue-like softness (34.6 kPa), high ionic conductivity (10.06 mS cm), excellent stretchability (360%), high transparency, robust adhesive strength (175.3 kPa) and interfacial toughness (1146 J m). Integrated into a flexible wearable device, the ultrathin gel ensures excellent skin conformity, user comfort, and high signal-to-noise ECG signal acquisition. Leveraging an artificial neural network, the system analyzes bradycardia ECG signals and achieves 96.88% accuracy in arrhythmia detection under cold conditions. This bioionic gel-based system presents a promising solution for early CAD diagnosis and prediction in extreme environments.
心血管疾病（CAD）是一个重大的全球公共卫生问题，低温对其死亡率有显著影响。在寒冷环境中进行稳定可靠的心电图（ECG）监测对于CAD的早期检测和治疗至关重要。然而，现有的皮肤传感器在低温下难以平衡抗冻性、透气性、柔韧性、导电性和粘附性。在此，我们引入一种溶剂交联策略和原位转移方法来制备超薄生物离子凝胶，其冰点低于-80°C，厚度仅为12.6μm。离子液体溶剂与两性离子聚合物之间强烈而丰富的相互作用有效抑制低温结晶，形成坚韧且高粘附性的网络结构。该网络能够原位形成超薄形态，并可无缝转移到各种基材上。此外，溶剂交联网络保持较大的聚合物链间距，有利于快速的离子传输途径。即使在零下温度下，该凝胶仍保持其多功能性，表现出类似组织的柔软度（34.6 kPa）、高离子导电性（10.06 mS cm）、出色的拉伸性（360%）、高透明度、强大的粘附强度（175.3 kPa）和界面韧性（1146 J m）。集成到柔性可穿戴设备中，超薄凝胶可确保出色的皮肤贴合性、用户舒适度以及高信噪比的ECG信号采集。利用人工神经网络，该系统分析心动过缓ECG信号，并在寒冷条件下心律失常检测中达到96.88%的准确率。这种基于生物离子凝胶的系统为极端环境下CAD的早期诊断和预测提供了一种有前景的解决方案。
