Smart Hydrogel Technology Enables Stage-Specific Treatment of Infected Wounds

A research team from Fudan University has developed a hydrogel technology that can sense pH changes in wound environments and dynamically release functional agents, enabling a switch from antibacterial action to tissue repair. Constructed from an interpenetrating network of sodium alginate and carboxymethyl chitosan, and loaded with tannic acid and zinc-doped bioactive glass, the hydrogel rapidly releases antibacterial molecules during infection and gradually delivers regenerative ions during healing. This represents the first demonstration of precise, stage-specific control of infected wound treatment through microenvironment-responsive mechanisms.

Led by Prof. Xiangchao Meng, the team designed a material that does not just cover wounds but understands what is happening and responds in real-time. In an acidic wound environment typical during infection, the gel contracts and releases tannic acid to kill bacteria and reduce oxidative stress. As healing progresses and the pH 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, with preclinical rat models showing over 90% wound closure in just 14 days, significantly outperforming standard treatments.

Histological analysis revealed enhanced collagen deposition, reduced inflammation, and improved blood vessel formation. 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 like diabetic foot ulcers or post-surgical infections. The research, detailed in the journal Biomedical Technology, represents a step toward intelligent wound management where materials can listen to the body and respond accordingly.

The team is now exploring clinical translation and broader applications of this technology. The work was supported by multiple funding sources including the Youth Program of Minhang Hospital, Shanghai Minhang District Medical Specialty Construction Project, Natural science research projects of Minhang District, and Zhejiang Provincial Medicine and Health Technology Project. The original research is available at https://doi.org/10.1016/j.bmt.2025.100120.