Transparent, Elastic Wound Gel Based on Chitosan: New Perspectives for Wound Healing

The efficient treatment of wounds remains a major challenge in modern medicine. Infections, in particular, are one of the main factors that can delay or even prevent healing. While traditional dressings primarily serve a protective function, the development of active, multifunctional wound dressings has increasingly come into focus.

A recent study demonstrates how polyvinyl alcohol (PVA) and chitosan, combined with silver nanoparticles, can form an innovative wound gel that not only exhibits antibacterial properties but also serves as a carrier for drugs.

Chitosan as a Key Material

Chitosan, a biopolymer derived from chitin, offers several properties that make it especially attractive for wound care applications:

• Biocompatibility and biodegradability: Chitosan is well tolerated by the body and can be naturally broken down.
• Antimicrobial activity: Even without additives, chitosan inhibits the growth of many bacterial species.
• Film-forming ability: In combination with PVA, stable and elastic hydrogel films can be produced.

In the study, a highly deacetylated chitosan (≥ 90%) was used, which, due to its high density of amino groups, shows particularly strong reactivity. For similar applications, chitosans with medium to high degrees of deacetylation are suitable, as they provide a good balance between mechanical stability and biological activity.

Silver Nanoparticles for Strong Antibacterial Action

The hydrogel was additionally enriched with silver nanoparticles, which were synthesized using a redox method. These particles show broad-spectrum antibacterial activity against both Gram-positive and Gram-negative bacteria. A notable advantage: unlike many antibiotics, silver nanoparticles are far less prone to resistance development.
Embedding silver nanoparticles into the PVA/chitosan matrix resulted in multiple benefits:

• High mechanical stability: The gel remains flexible and resistant to fracture.
• Protein adsorption: Microorganisms adhere to the surface, where they are effectively inactivated by silver particles.
• Transparency: With a light transmittance above 75%, the gel allows direct monitoring of the wound without removing the dressing.
  pH-Responsive Drug Release

Release profile depends on pH

Another exciting feature is the gel’s ability to load drugs and release them in a controlled manner. The study showed that the release profile depends on pH:

• Under acidic conditions (e.g., in infected wounds), drug release occurs more rapidly.
• Under neutral to alkaline conditions, release is slower - ideal for long-term treatment.

This means the composition of the gel can be adjusted depending on whether rapid or sustained release is needed.

Conclusion and Outlook
The combination of PVA, highly deacetylated chitosan, and silver nanoparticles clearly demonstrates how modern biomaterials can evolve from passive protection to active wound healing. The resulting transparent, elastic wound gel has the potential not only to prevent infections but also to deliver drugs directly to the wound site.
This research paves the way for the development of intelligent wound dressings that accelerate healing, reduce patient burden, and could transform clinical practice in the near future.

Reference
F. Aldakheel, D. Mohsen, M. M. El Sayed, S. A. Alduraywish, “Silver Nanoparticles Loaded on Chitosan-g-PVA Hydrogel for Wound-Healing Applications”, Molecules 2023, 28(7): 3241.

First published on 17th of October 2025

Revised on 17th of October 2025