Polymerizable rotaxane hydrogels for three-dimensional printing fabrication of wearable sensors

• Main Authors: Xiong, Xueru, Chen, Yunhua, Wang, Zhenxing, Liu, Huan, Le, Mengqi, Lin, Caihong, Wu, Gang, Wang, Lin, Shi, Xuetao, Jia, Yong-Guang, Zhao, Yanli
• Other Authors: School of Chemistry, Chemical Engineering and Biotechnology
• Format: Article
• Language: English
• Published: 2023
• Subjects: Engineering::Bioengineering; Body Movement; Three Dimensional Printing
• Online Access: https://hdl.handle.net/10356/168754
• Institution: Nanyang Technological University

While hydrogels enable a variety of applications in wearable sensors and electronic skins, they are susceptible to fatigue fracture during cyclic deformations owing to their inefficient fatigue resistance. Herein, acrylated β-cyclodextrin with bile acid is self-assembled into a polymerizable pseudorotaxane via precise host-guest recognition, which is photopolymerized with acrylamide to obtain conductive polymerizable rotaxane hydrogels (PR-Gel). The topological networks of PR-Gel enable all desirable properties in this system due to the large conformational freedom of the mobile junctions, including the excellent stretchability along with superior fatigue resistance. PR-Gel based strain sensor can sensitively detect and distinguish large body motions and subtle muscle movements. The three-dimensional printing fabricated sensors of PR-Gel exhibit high resolution and altitude complexity, and real-time human electrocardiogram signals are detected with high repeating stability. PR-Gel can self-heal in air, and has highly repeatable adhesion to human skin, demonstrating its great potential in wearable sensors.