A research team from Fudan University has developed a smart hydrogel that senses the pH of infected wounds and automatically shifts its therapeutic function from fighting infection to promoting tissue repair. The material, described in a study published in Biomedical Technology, represents a significant advance in intelligent wound management by providing precise, stage-specific control over healing.
Constructed from an interpenetrating network of sodium alginate and carboxymethyl chitosan, the hydrogel encapsulates two key bioactive components: tannic acid, a natural antibacterial agent, and zinc-doped bioactive glass that releases ions known to support healing. The gel responds to the wound microenvironment; during infection, when the pH is acidic, the gel contracts and releases tannic acid to kill bacteria and reduce oxidative stress. As the infection clears and the wound environment becomes more alkaline, the gel expands and gradually releases zinc and calcium ions that promote angiogenesis and tissue regeneration.
“This dual-function system adapts to each healing stage and actively assists the process,” said Prof. Xiangchao Meng, who led the study. In preclinical rat models with infected wounds, the hydrogel achieved over 90% wound closure within 14 days, significantly outperforming standard treatments. Histological analysis revealed enhanced collagen deposition, reduced inflammation, and improved blood vessel formation. Notably, the gel remains inert in healthy tissue and activates only under pathological conditions, reducing drug overuse and limiting the need for frequent dressing changes. This feature makes it especially promising for treating complex wounds such as diabetic foot ulcers or post-surgical infections.
The team is now exploring clinical translation and broader applications. “This is a step toward intelligent wound management,” Meng added. “Materials that can listen to the body and respond accordingly could redefine how we treat injury and disease.” The study was supported by several grants, including the Youth Program of Minhang Hospital and the Zhejiang Provincial Medicine and Health Technology Project. The full research paper can be accessed at https://doi.org/10.1016/j.bmt.2025.100120.
