Anti-Microbial Effects of Conductive Copper Nanoparticle Film

Abstract

Novel infection control methods are needed to prevent further increases in the morbidity and mortality associated with hospital acquired infections. One method is to minimize bacterial transmission is to prevent bacterial growth on hospital surfaces. Copper has anti-microbial properties but is used sparingly in health care settings due to the cost associated with retrofitting surfaces with copper sheet metal or less durable foil. However, copper nanoparticles (CNPs) embedded in a polymer matrix may be similarly anti-microbial, which would offer a viable alternative to copper metal. In this pilot study, we created films with various densities of CNPs and tested their effectiveness in killing bacteria commonly associated with hospital-acquired infections. We found that films with mass ratios greater than 1:2 of CNP to polymer matrix solution killed Streptococcus pyogenes and Staphylococcus aureus more effectively than a copper plate, while the killing of Pseudomonas aeruginosa was similar when exposed to either surface. We also found that passing an electrical current through the CNP film increased the anti-microbial effect of the films against P. aeruginosa even more so than electrified Cu plates. CNP films, which are relatively inexpensive, could be sprayed directly onto hospital surfaces to reduce the incidence of hospital-acquired infections.

Keywords

• antimicrobial film
• copper nanoparticles
• antimicrobial copper
• mrsa