The Influence of Surface Scratches on Copper's Antibacterial Activity

Abstract

Copper metal is capable of killing more than 99.9% of bacteria upon contact, and has been researched as an alternative material to hospital surfaces with aim to prevent hospital-acquired infections. Because copper is a malleable metal, it is more likely to acquire surface scratches than other common materials in high-traffic health care facilities. To investigate the effects these scratches may have on copper's antibacterial activity, we inoculated scratched and unscratched copper C110 with either E. coli ATCC 11303 or S. carnosus 51365 and quantified the bacteria present at various time intervals. We found no significant difference in the antibacterial activity of copper between the two surface textures, with 99.9% of E. coli bacteria killed within 10 minutes. This suggest that copper surfaces implemented in health care facilities would not require extensive maintenance of smooth surfaces to retain their bactericidal effects. Additionally, we found a significantly greater concentration of bacteria present on stainless steel compared to copper, supporting the claims that copper surfaces could help decrease the transmission of hospital-acquired infections.