Scanning Electron Microscopy Analysis of Biofilm-Encased Bacteria Exposed to Cuprous Oxide-Impregnated Wound Dressings

Microbial infections in wounds can significantly delay the healing process, with bacteria often forming protective biofilms that shield them from external threats. In this study, we evaluated the impact of copper oxide-impregnated wound dressings (referred to as COD) on a bacterial mixture comprising common Gram-positive and Gram-negative wound pathogens encased in biofilm. The bacterial mix was exposed to COD or control dressings for 0, 1, 2, and 3 h, and the effects were analyzed using scanning electron microscopy. After just 1 h of exposure to COD, notable leakage of bacterial cytoplasmic contents was observed. By the 3 h mark, the Gram-negative bacteria exhibited a formation of holes in their cell walls, while Gram-positive bacteria showed a reduction in cell width. These findings demonstrate the ability of COD to effectively kill bacteria even when protected by biofilm, supporting clinical observations of its efficacy in managing infected wounds.