Fu Qiang, Tang Junxiao, Wang Weimin, Wang Rongjie
China Shipbuilding Industry Corporation, Research Institute 712, Wuhan 430064, China.
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China.
Gels. 2025 Jan 11;11(1):59. doi: 10.3390/gels11010059.
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-thaw 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/m, more than 3 times that of the PVA hydrogel (39.17 kJ/m). 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.
具有拉伸性和导电性的蛋白质基水凝胶在可穿戴电子设备中具有潜在应用。然而，蛋白质基生物复合水凝胶的发展仍然有限。在这项工作中，我们使用天然铁蛋白通过重复冻融法制备了一种聚乙烯醇/铁蛋白生物复合水凝胶。在这种生物复合水凝胶中，铁蛋白作为纳米弹簧与聚乙烯醇网络形成氢键，这降低了聚乙烯醇的结晶度并显著提高了水凝胶的拉伸性。聚乙烯醇/铁蛋白水凝胶的断裂应变是203%，断裂应力是112.2千帕。聚乙烯醇/铁蛋白水凝胶的断裂韧性显著提高到147.03千焦/平方米，是聚乙烯醇水凝胶（39.17千焦/平方米）的3倍多。此外，铁蛋白的游离残基和铁离子赋予生物复合水凝胶增强型离子导电性（0.15西门子/米）。由这种水凝胶构建的应变传感器在用于关节运动监测时显示出良好的灵敏度（在150%应变下的应变系数=1.7）、准确的实时电阻响应和良好的长期循环工作稳定性。结果表明，通过简便方法制备的聚乙烯醇/铁蛋白生物复合水凝胶对于柔性应变传感器具有增强的拉伸性和导电性。这项工作为可穿戴电子设备的蛋白质基水凝胶制备开发了一种新方法。
