Concentration- and roughness-dependent antibacterial and antifungal activities of CuO thin films and their Cu ion cytotoxicity and elution behavior

Abstract

In this study, we aimed to evaluate the antibacterial and antifungal properties, cytotoxicity, and elution behavior of copper oxide (CuO) thin films with varying concentrations and roughness values. CuO films greater than 0.2 mol % showed 99.9 % antimicrobial activity against Escherichia coli, Staphylococcus aureus, Campylobacter jejuni, and Penicillium funiculosum. Cu ions were found to be noncytotoxic in New Zealand white rabbits. The concentration of Cu ions from CuO thin films eluted in drinking water in 24 h at 100 °C was 0.014 μg L(-1), which was below the standard acceptable level of 0.02 μg L(-1). The transmittance of CuO thin film-coated glass was similar to that of parent glass. The antimicrobial activity, cytotoxicity, elution behavior, and transmittance of CuO deposited on glass suggest that these films could be useful in household devices and display devices.

Tailor the antibacterial efficiency of copper alloys by oxidation: when to and when not to

“…Last but not the least, although it was only the antibacterial efficiency against E. coli that was investigated in the present study, copper surfaces have actually shown capability against a very broad range of bacteria [3,7,52], viruses [53][54][55], and fungi [25,52,56]. Therefore, the strategy proposed here is also encouraging in many scenarios where the general antimicrobial property is needed.…”

“…Copper oxide surfaces with antibacterial activity have been successfully synthesised by various methods, e.g. chemical vapour deposition [20], sputtering [21], wet chemical method [23], hydrothermal method [24], and spin coating [25].…”