Cu/Zn galvanic couples composite antibacterial dressings prepared by template-assisted magnetron sputtering

In this study, Cu/Zn strips were deposited on a commercial low adhesive polyethylene/Cotton/polyethylene dressing (PE/Cotton/PE) by template-assisted magnetron sputtering. The electrochemical measurement, X-ray photoelectron spectroscopy, and finite element simulation results proved the forming of galvanic couples between Cu and Zn strips when activated by wound exudate. Antibacterial activity evaluated in vitro shows that the Cu/Zn@PE/Cotton/PE exhibits excellent antibacterial activity towards Staphylococcus aureus. Its antibacterial ability seems essentially attributed to the microscale electric fields and the enhancing ionization of Cu2+ and Zn2+ due to the nano-galvanic couple activation. Furthermore, benefit from the low coating area (50%) of Cu/Zn strips, the cytotoxicity study evaluated in vitro illustrates the nontoxic nature of the Cu/Zn@PE/Cotton/PE. Overall, the deposition method of Cu/Zn galvanic couples on dressings in this study shed new light on designing electroactive antibacterial wound dressings.