Mussel-Inspired Conductive Hydrogel with Self-Healing,\nAdhesive, and Antibacterial Properties for Wearable Monitoring

Abstract

Hydrogels\nwith multifunctional properties have attracted considerable\ninterest owing to their wide range of applications in soft robotics,\nwearable device development, and tissue engineering. In this study,\nan adhesive, self-healing, and antibacterial conductive poly­(dopamine\nmethacrylate-<i>co</i>-methacrylatoethyl trimethyl ammonium\nchloride-<i>co</i>-acrylic acid) (PDDA) hydrogel was prepared\nby the free-radical copolymerization of dopamine methacrylate (DMA),\nmethacrylatoethyl trimethyl ammonium chloride (DMC), and acrylic acid\n(AA). The adhesion property of the PDDA hydrogel was explored by regulating\nthe feeding ratios of AA, DMA, and DMC. The hydrogel with a DMA/DMC/AA\nmolar ratio of 1:4:40 exhibited strong adhesion to various materials\nsuch as iron, wood, rubber, glass, polytetrafluoroethylene, and plastic.\nMeanwhile, the hydrogel showed good antibacterial properties, which\nhad a good inhibitory effect against Escherichia coli (37%) and Staphylococcus aureus (44%).\nIn addition, because of its non-covalent bond interactions in the\ncross-linking network, the hydrogel exhibited excellent self-healing\nproperty when damaged. Moreover, the excellent ductility, biocompatibility,\nand adhesion property of the hydrogel allow better adhesion to the\nskin surface and conductivity to monitor the physiological activities\nof the human body by means of the electrical signals recorded using\nthe transformation of strain responses. The self-healing, adhesive,\nantibacterial, biocompatible, and conductive hydrogel has a wide range\nof applications in electronic skin and wearable devices.