An Injectable, Wound-Adapting, Self-Healing Hydrogel for Fibroblast Growth Factor 2 Delivery System in Tissue Repair Applications

Rapid wound healing is a fundamental health concern and poses a critical challenge for healthcare systems worldwide. Here, we developed an injectable, dynamic, self-healing hydrogel serving as a fibroblast growth factor 2 (FGF2) delivery system for tissue repair applications. Benzaldehyde-terminated polyethylene glycol (BAPEG) was synthesized and crosslinked with N-Succinyl-chitosan (SCS) through reversible Schiff-base reaction to form a dynamic self-healing hydrogel. Because it can be injected after gelation and self-heal into an integral part, the hydrogel could not only auto-adapt to the irregular wound surface to provide better protection but also encapsulate drugs homogeneously and implant into tissue with a less invasive strategy. As a result, the FGF2-loaded SCS/BAPEG hydrogel is able to significantly promote the process of angiogenesis, collagen deposition, and granulation tissue formation, as well as reduce inflammation. This study opens the door to self-healing hydrogels serving as a drug delivery system for tissue repair applications.