Self-Assembly of Naturally Small Molecules into Supramolecular Fibrillar Networks for Wound Healing

Self-assemblies of bioactively natural compounds into supramolecular hydrogels without structural modifications are of interest to improve their sustained releases and bioavailabilities in vivo. However, it is still a formidable challenge to dig out such a naturally small molecule with a meticulous structure which can be self-assembled to form a hydrogel for biomedical applications. Here, a new hydrogel consisting only of gallic acid (GA) via π-π stacking and hydrogen bond interactions, whereas none of GA analogues can form the similar supramolecular hydrogels, is reported. This interesting phenomenon is intriguing to further investigate the potential applications of GA hydrogels in wound healing. Notably, this GA hydrogel has rod-like structures with lengths varying from 10 to 100 µm. The biocompatibility and antibacterial tests prove that this well-assembled GA hydrogel has no cytotoxicity and excellent antibacterial activities against Escherichia coli and Staphylococcus aureus. Moreover, the GA hydrogel can significantly accelerate the process of wound healing with or without bacterial infections by mediation of inflammation signaling pathways. It is believed that the current study may shed a new light on the design of a supramolecular hydrogel based on self-assemblies of naturally small molecules to improve their bioavailabilities and diversify their uses in biomedical applications.