Non-technical Abstract The goal of the proposed work is to limit the transmission of the COVID-19 virus and influenza virus through the development of new antimicrobial materials. The work focuses on metal alloys that can be used to coat regularly touched surfaces. Such surfaces are a major contributor to the spread of a virus as they become contaminated by an infected individual and lay in wait to infect a healthy person without any direct contact between the two individuals. An effective antimicrobial coating can dramatically reduce the length of time a virus can survive on such surfaces through release of oxidized copper and in that way minimize the likelihood of transmission. In this work, the focus is on balancing the antimicrobial behavior of the materials with the other critical aspects of a coating, specifically, the corrosion and passivation behavior, the surface preparation, and the impact of cleaning. Surface preparation and cleaning are important factors since it is vital that any coating be robust and effective in real-world environments. By obtaining a thorough understanding of the corrosion behavior, it becomes possible to better understand the science underlying the antimicrobial behavior and enables the future development of coatings either targeted to other viruses or suitably broad-spectrum to address a wide range of viruses so that the threat of future pandemics can be addressed by this strategy.
The goal of this work is to determine the efficacy of antimicrobial functional copper-based alloys deployed as coatings in reducing the survivability of bacteria and viruses on high-touch surfaces. The process of mitigating virus viability is dependent on the concentration of copper ions released, the rate of release from the alloys as well as oxygen radicals produced as a result of electrochemical reactions, and the nature, concentration, and inoculum of the virus. These reactions and the fate of copper depend on alloy composition and the details of surface structure, morphology, and the nature of the passive oxide surface film produced by pretreatments and ambient exposure. A given copper cation concentration reduces virus viability depending on environmental factors and virus attributes. Hence, in this work virus viability is investigated using a palette of viruses representative of SARS-CoV-2 as well as influenza strains. Using a judicial selection of copper-based alloys and expected surface treatments as the starting point, the antimicrobial performance of these alloys, judged by virus unit death over time of exposure will be determined as a function of alloy composition and surface character produced by surface preparation. Detailed surface and electrolyte characterization is carried out to elucidate the details of the corrosion mechanism, which enable virus mitigation. This work seeks to enable the immediate selection of specific copper alloys for deployment as high-touch surfaces by answering the question of optimal alloy composition and treatment as well as affect future scientific principles of alloys further optimized for this function.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
