Self-healing conductive composite hydrogel for human motion and 3D cell culture monitoring

Abstract

Conductive hydrogels have emerged as versatile materials with promising applications in various fields, as they possess the ability to convert external forces and deformations into electrical signals, enabling them to sense physical and chemical stimuli. However, the development of conductive hydrogels faces a challenge in balancing conductivity and mechanical strength demands. We incorporated lignin-tannic acid (lignin-TA) particles as physical crosslinkers to enhance their mechanical properties. Additionally, the multi-hydroxyl structure of hydroxypropyl cellulose molecules facilitated the formation of a semi-interpenetrating polymer network through hydrogen bond interactions. Furthermore, the bond strength between the lignin-TA-polyacrylamide networks was intensified, resulting in an elevation of their conductivity. This enhancement was achieved by harnessing the electrostatic forces and metal coordination interactions between Fe³⁺ ions and TA molecules. The resulting hydrogel exhibited outstanding mechanical characteristics due to its unique network structure, combining physical and chemical bonds. Taking advantage of the hydrogel’s unique network structure, we successfully utilized its self-adhesion, self-healing capabilities, electromechanical properties, and biocompatibility to monitor human activities and cell proliferation.

摘要

导电水凝胶已在多个领域崭露头角, 因为它具备将外界压力和形变转化为电信号的能力, 可实现对物理和化学刺激的灵敏感知. 然而, 在导电水凝胶的研发中, 需要克服平衡导电性和机械强度的挑战.本项工作中, 为了提高导电水凝胶的力学性能, 我们采用了多重策略.首先, 引入了木质素-丹宁酸(lignin-TA)颗粒作为物理交联剂, 同时充分利用羟丙基纤维素分子的多羟基结构, 促进水凝胶半互穿聚合物网络的形成. 随后, 通过利用Fe³⁺离子和TA分子之间的静电力和金属配位相互作用, 进一步增强了聚合物网络之间的键合强度, 提高了水凝胶的导电性. 最终, 所制备的导电水凝胶以其独特的网络结构, 成功融合了物理和化学键的特性, 并展现出卓越的自粘附、自愈合能力、电机械性能和生物相容性. 这使其成为一个可用于监测人体活动和细胞增殖的理想材料.