Polymicrobial wound infections often require high dosages of antibiotics and fungicides. However, prolonged antimicrobial therapies are associated with potential systemic side effects and an increased risk of the development of drug-resistant microbes. With this focus, we aimed at developing chitosan bandages loaded with antimicrobial drug (ciprofloxacin and fluconazole) nanoparticles for a sustained slow release of drugs. The particle sizes of the prepared ciprofloxacin- and flucanazole-loaded fibrin nanoparticles were observed to be 132 ± 16 and 175 ± 17 nm, respectively. The chitosan bandages with drug-containing nanoparticles were flexible and had adequate tensile strength and porosity of 80-85%, which would favor excess exudate absorption in an infectious wound. The in vitro toxicity of the bandages studied against the human dermal fibroblast cell line proved its cytocompatibility. Ciprofloxacin and fluconazole were released from bandages for up to 14 days in a sustained manner. The antimicrobial-drug-loaded bandages showed significant antimicrobial activity toward polymicrobial cultures of Candida albicans, Escherichia coli, and Staphylococcus aureus in vitro and ex vivo. In vivo studies were conducted on a polymicrobially infected rat wound model. A significant reduction in microbial load was obtained upon application of antimicrobial-drug-loaded chitosan bandages in vivo.
Keywords: antimicrobial agents; fibrin nanoparticles; nanocomposite chitosan bandage; polymicrobial infection.