Dual Self-Assembly of Puerarin and Silk Fibroin into Supramolecular Nanofibrillar Hydrogel for Infected Wound Treatment.

The treatment of infected wounds remains a challenging biomedical problem because of the complex microenvironment at the wound bed. Some natural bioactive small-molecule hydrogelators with unique rigid structures can self-assemble into supramolecular hydrogels, serving as supporting dressings and therapeutic agents for wound healing. However, they are still suffered from low structural stability and bio-functionality. Herein, we proposed a supramolecular hydrogel antibacterial dressing with a dual nanofibrillar network structure. A nanofibrillar network created by small-molecule hydrogelator, puerarin extracted from the traditional Chinese medicine Pueraria, was interconnected with a secondary macromolecular silk fibroin nanofibrillar network induced by Ga ions via charge-induced supramolecular self-assembly. The resulting hydrogel features adequate mechanical strength for sustainable retention at wounds. The good biocompatibility and efficient bacterial inhibition were also obtained when the Ga ion concentration was 0.05%. Otherwise, the substantial release of Ga ions and puerarin endows the hydrogel with excellent hemostatic and antioxidative properties. In vivo evaluation on a mouse infected wound model demonstrates that its healing effect outperformed that of a commercially available silver-containing wound dressing. The experimental group successfully achieved a 100% wound closure rate on day 10 of treatment. This study sheds a new light on the design of nanofibrillar hydrogels based on supramolecular self-assembly of naturally derived bioactive and/or biofunctional molecules as well as their clinical use for the treatment of chronic infected wounds. This article is protected by copyright. All rights reserved.