Entanglement-DrivenAdhesion, Self-Healing, and HighStretchability of Double-Network PEG-Based Hydrogels

Hydrogels that are capable of wet adhesion and self-healing can enable major advances in a variety of biomedical applications such as tissue regeneration, wound dressings, wearable/implantable devices and drug delivery. We hereby developed an innovative but simple strategy to achieve adhesive, self-healing and highly stretchable double network hydrogels, which were composed of a primary covalent polyethylene glycol diacrylate (PEGDA) network in combination with a non-covalent network of highly diffusive, giant PEG chains. The adhesion to substrates including tissue matrices was instant and repeatable due to the the diffusive PEG chains that can spontaneously penetrate and entangle with the substrate network. Combining the intrinsic biocompatibility of PEG and rational design for tuning the hydrogel network properties, we exemplarily demonstrated that this hydrogel to be used as 3D matrix for cell culture, or as tissue adhesives for wound healing. In vivo study showed the hydrogel capable to effectively tr...