Poly(vinyl alcohol)/chitosan hydrogels with electrochemically synthesized silver nanoparticles for wound dressing applications

Polymer-based hydrogel materials are excellent candidates for new-generation wound dressings with improved properties, such as high sorption ability, good mechanical properties and low adhesiveness. Cross-linked hydrogel matrices also serve as excellent carriers for controlled release of antibacterial agents, such as silver nanoparticles (AgNPs), which are preferred over conventional antibiotics due to low propensity to induce bac­terial resistance. In this work, we aim to produce novel silver/poly(vinyl alco­hol)/chitosan (Ag/PVA/CHI) hydrogels for wound dressing applications. The electro­chemi­cal AgNPs syn­thesis provided facile and green method for the reduction of Ag+ ions inside the hydrogel matrices, without the need to use toxic chemical reducing agents. The forma­tion of AgNPs was confirmed using UV-visible spectroscopy, scanning and transmis­sion electron microscopy. Release kinetics was investigated in modified phosphate buffer solution at 37 °C to mimic physiological conditions. Release profiles indicated “burst release” behavior, which is beneficial for wound dressing applications. The antibacterial activity was evaluated against Staphylococcus aureus and Escherichia coli strains using disc-diffusion test, and non-toxicity of hydrogels was proved by dye-exclusion test. The obtained results confirmed strong potential of Ag/PVA/CHI hydrogels for biomedical applications.