Sun Hao, Dong Zhibin, Kou Xinyue, Zhao Qiaoqiao, Shi Lei, Ma Yuning, Ma Yuxia
Key Laboratory of New Material Research Institute, Institute of Pharmacy, Shandong University of Traditional Chinese Medicine Jinan 250355 China
Key Laboratory of Pulp and Paper Science & Technology of Ministry of Education, State Key Laboratory of Biobased Material and Green Papermaking, Faculty of Light Industry, Qilu University of Technology (Shandong Academy of Sciences) Jinan 250353 China.
RSC Adv. 2023 Feb 15;13(9):5762-5769. doi: 10.1039/d3ra00546a. eCollection 2023 Feb 14.
Multifunctional integration is the focus of hydrogel-based flexible sensors, and formation of a dual network (DN) could shed light on the fabrication of hydrogels with multifunctionality and enhanced properties. In this study, a DN hydrogel was fabricated by the self-assembly of herbal molecule glycyrrhizic acid (GA) as the first hydrogel network and subsequent photocrosslinking of methacrylated sodium alginate (SA-MA) to form the second network. Profiting from the good compatibility between the two hydrogel networks, the obtained DN hydrogels with a homogeneous porous microstructure were endowed with remarkably enlarged stretching (114.5%) and compression (74.4%) strains. In addition, they were demonstrated to display excellent bacteriostatic activity (>99.9%) against and owing to the synergetic antibacterial effect of GA and SA-MA. The DN hydrogels as strain sensors possessed high sensitivity (GF = 1.39), linear sensing ( > 0.99), rapid response (180 ms), and good stability (1300 times) for human motion detection. Besides, the DN hydrogels could also be used to conduct pressure sensing such as application of heavy weights and even human pulses. All results suggest that the developed DN hydrogels have great potential in serving as epidermal and implantable flexible sensors for human health monitoring.
多功能集成是水凝胶基柔性传感器的研究重点，双网络（DN）的形成有助于制备具有多功能性和增强性能的水凝胶。在本研究中，通过草药分子甘草酸（GA）自组装形成第一个水凝胶网络，随后甲基丙烯酸化海藻酸钠（SA-MA）进行光交联形成第二个网络，制备了一种DN水凝胶。得益于两种水凝胶网络之间的良好相容性，所制备的具有均匀多孔微结构的DN水凝胶具有显著增大的拉伸应变（114.5%）和压缩应变（74.4%）。此外，由于GA和SA-MA的协同抗菌作用，它们对大肠杆菌和金黄色葡萄球菌表现出优异的抑菌活性（>99.9%）。作为应变传感器的DN水凝胶在人体运动检测方面具有高灵敏度（GF = 1.39）、线性传感（R²>0.99）、快速响应（180 ms）和良好的稳定性（1300次）。此外，DN水凝胶还可用于压力传感，如重物施加甚至人体脉搏检测。所有结果表明，所开发的DN水凝胶在用作人体健康监测的表皮和可植入柔性传感器方面具有巨大潜力。
