Highly Adhesive, Conductive, and Self-Healing Hydrogel with Triple Cross-Linking Inspired by Mussel and DNA for Wound Adhesion and Human Motion Sensing

Hydrogel has a similar structure and function as the extracellular matrix and is expected to be used for wound adhesion and hemostasis. However, traditional hydrogels have poor adhesion and no self-healing function, and mechanical properties are also limited. Inspired by mussel and adherent DNA, the triple-cross-linking conductive self-healing hydrogel (CaSA-GAD hydrogel) containing calcium ions (Ca2+), sodium alginate, acrylated guanine, acrylamide, and acrylated dopamine was constructed through UV irradiation, including a G–C pairing hydrogen bond dynamic network, a chemical cross-linking network, and an ionic cross-linking dynamic network. The hydrogel exhibits strong adhesion to various surfaces and peeling properties in the bonding of tissues. With high toughness, the hydrogel can be stretched and compressed without damage. The self-healing property further ensures the mechanical properties of the hydrogel. By loading calcium ions to reduce the impedance of the hydrogel greatly, the wound can be monitored at the same time when the wound is bonded. Both fresh and freeze-dried hydrogel can be used to bond the wound on pork stomach and the scope of application of as wound adhesive increases. In addition, the hydrogel can be used as a sensitive sensor to monitor human movement.