The development of a new generation of wound coverings, such as those based on silver-containing polyvinyl alcohol hydrogels, is required to combat microbial infections. Such hydrogels are a reticulated polymer system that is biocompatible with the tissues of living organisms and allows imitation of biological tissues. This is due to the water-retention capacity, film-forming properties of the gels, vapor permeability, and the ability to absorb a degree of wound exudate.
Silver nanoparticles are known for their antiseptic, anti-inflammatory, and multi-level antimicrobial effects. However, silver nanoparticles are highly cytotoxic and also prone to aggregation, which can lead to a loss of antimicrobial properties.
To solve the problem of silver particle aggregation in this work, functional substances were used that can be evenly distributed in the matrix of polyvinyl alcohol. For this purpose, nanosized p-β-carboxyethenylphenoxy-p-formylphenoxycyclotriphosphazene was used as a crosslinking agent. This compound is nontoxic, which makes its application safe for wound healing. Due to the fact that phosphazene has carboxyl and aldehyde functional groups at the same time in its composition, it is able to act both as a crosslinking agent and as a carrier of silver ions. Based on the developed system, wound coverings were obtained using different amounts of crosslinking agent. It was found that as the content of the crosslinking agent decreases, the degree of water absorption of the material increases. At the same time, wound coverings with crosslinking agent concentration of 4,5 wt.% have the highest water absorption.
After silver introduction into the hydrogel, its X-ray fluorescence elemental analysis was carried out. The silver content was 0.87 wt.%, which is sufficient to exhibit antiseptic properties.