Abstract
Burn wounds are debilitating injuries that contribute significantly to global morbidity and mortality. The disruption of skin integrity elevates the risk of infection, which can impede healing and potentially lead to sepsis. Furthermore, antibiotic resistance, primarily driven by biofilm formation, poses a major challenge to effective treatment. This study is aimed at evaluating the potential of positively charged carbon dots (CDs) in inhibiting biofilm formation, with possible applications in wound care. Specifically, carbon nanodots (CDs-NH(2)) were tested in vitro against both planktonic cells and biofilms formed by a range of pathogens, including the Gram-positive bacterium Staphylococcus aureus, the Gram-negative bacterium Escherichia coli, the yeast Candida albicans, and the mold Aspergillus brasiliensis. Additionally, the activity of CDs-NH(2) was assessed against polymicrobial biofilms composed of S. aureus and C. albicans. The in vivo efficacy of CDs-NH(2) was evaluated using the Galleria mellonella burn wound infection model for both monomicrobial and polymicrobial infections. The ability of CDs-NH(2) to penetrate fungal cells was demonstrated by fluorescence microscopy analysis. Biomass quantification showed that CDs-NH(2) reduced biofilm formation by over 50% for C. albicans, E. coli, and A. brasiliensis, as well as for C. albicans-S. aureus cocultures, at concentrations below 62.5 μg/mL. The in vivo studies further confirmed the antimicrobial activity of CDs-NH(2) against all tested strains in burn wound infections. Strategies that target biofilm-forming microorganisms at wound sites may enhance infection control and promote wound healing.