Injectable silk-kudzu hydrogel achieves complete wound closure in laboratory tests

Injectable silk-kudzu hydrogel achieves complete wound closure in laboratory tests Gaby Clark Scientific Editor Robert Egan Senior Editor Researchers at the Terasaki Institute for Biomedical Innovation have developed an injectable hydrogel, a water-based gel material, made from silk proteins and a plant-derived compound. In laboratory tests, the material promoted complete wound closure within 72 hours, suggesting a potential new approach to minimally invasive soft tissue repair. Wounds that are difficult to reach or slow to heal present a persistent challenge in medicine. Current biomaterials, materials engineered to interact with biological systems, often require surgery to implant, lack the mechanical flexibility needed to conform to soft tissue or fail to support robust cell growth. The new material combines two naturally occurring substances. The first is silk fibroin (SF), a protein from silkworm cocoons that is well tolerated by the body. The second is puerarin (PUE), a bioactive compound from the root of the kudzu plant with anti-inflammatory and antioxidant properties. The team systematically tested five formulations containing increasing amounts of puerarin, ranging from 1% to 5%, combined with a fixed concentration of silk fibroin. Published in ACS Omega, the study found that puerarin strengthened the hydrogel network through hydrogen bonding, a type of physical attraction between molecules. Importantly, this process did not alter the underlying protein structure of silk fibroin. Higher puerarin concentrations produced denser internal networks and increased mechanical stability. The material could also flow through a fine 27-gauge needle under pressure and recover its gel-like structure once injected. In laboratory studies, human skin cells exposed to the hydrogels showed cell viability above 95% from day 1. Cells cultured with the material achieved complete wound closure within 72 hours across all formulations tested. The highest puerarin concentration showed about 60% wound closure within the first 24 hours alone. No signs of toxicity were observed in any tested formulation. "What excited us most was seeing complete wound closure in all formulations in 72 hours. That result, combined with the material's ability to be injected through a fine needle, suggests real clinical relevance for soft tissue applications," said Dr. Bruna V. Quevedo, visiting scholar at the Terasaki Institute and first author of the publication. "Injectable biomaterials that can be delivered through a small needle and still support tissue repair have the potential to reduce the burden of invasive procedures for patients. This work brings us a step closer to that goal," said Dr. Menekse Ermis Sen, a Terasaki fellow at the Terasaki Institute for Biomedical Innovation. This research could support the development of minimally invasive treatments for soft tissue injuries and chronic wounds. Further studies in animal models are needed to validate the material's performance under real physiological conditions. Publication details Bruna V. Quevedo et al, Injectable Silk Fibroin–Puerarin Hydrogels with Tunable Supramolecular Organization as a Potential Platform for Tissue Engineering, ACS Omega (2026). DOI: 10.1021/acsomega.6c02412 Journal information: ACS Omega Provided by Terasaki Institute for Biomedical Innovation