Novel antibacterial hydrogels based on gelatin/polyvinyl-alcohol and graphene oxide/silver nanoconjugates: formulation, characterization, and preliminary biocompatibility evaluation.

Antibiotic resistance has become a major public health problem generated by their excessive and inappropriate use. This is worrisome because multiple microbial infections that could traditionally be treated without major complications are now considerably challenging to treat. In this regard, research in this field has been focused on searching for new molecules capable of arresting these microbial infections with high effectiveness, including antimicrobial peptides (AMP) and various nanomaterials. Here, we proposed a novel topical hydrogel treatment based on a polymeric network of gelatin-polyvinyl alcohol-hyaluronic acid encapsulating a graphene oxide (GO) nanoconjugate on which silver nanoparticles (Ag NPs) have been grown. This treatment is intended to be stable, biocompatible, non-toxic, pleasant to skin contact, provide bioavailability of the active agent for a prolonged period in the affected skin area where its application is required and inhibit microbial growth effectively. The nanocomposite hydrogels were characterized in terms of microstructure, thermal resistance, rheological behavior, particle size distribution, texture profile and physical stability, as well as a one-month accelerated stability study. The satisfactory results in terms of physical chemistry, stability on storage modulus (G'), TSI values, and microstructure allowed choosing some points of the experimental design to encapsulate the GO-Ag NPs nanoconjugates. The biological evaluation of these nanocomposites showed that the treatments are biocompatible as they have a very low hemolytic effect (less than 5%) and a moderate platelet aggregating capacity (35%-45%). Finally, 100% of bacterial growth was inhibited by the action of the topical nanocomposite hydrogel treatments. These results led to affirm that these treatments can have an excellent performance in this application as well as in wound healing and dressing, bioadhesives, tissue engineering, and other biomedical applications.