Novel Materials that Enhance the Effectiveness of Ultraviolet Disinfection
Healthcare associated infections and foodborne illnesses are both significant public health issues, and are both attributed, at least in part, to the inadequate disinfection of contaminated surfaces. Traditional sanitation methods, including manual cleaning with sodium hypochlorite or quaternary ammonium compounds, are sometimes ineffective and often poorly implemented.
Ultraviolet germicidal irradiation (UVGI) is a very effective method of disinfecting surfaces, and the use of UVGI in healthcare facilities has grown significantly over the past five years. UV devices are now commonly used as a supplemental step in the cleaning of patient rooms and emergency rooms. However, the efficacy of UVGI in these applications can be limited by complicated room geometries and is significantly affected by the surface properties of the materials found throughout these facilities.
Our research seeks to develop novel materials and simulation methods that optimize the disinfection of healthcare and food service facilities. This has led to the development of surface coatings that enhance UVGI by diffusely scattering germicidal light throughout a three-dimensional space. Clinical studies of these materials have shown that they significantly improve the disinfection of common hospital pathogens, such as Methicillin-resistant Staphylococcus aureus (MRSA) and Clostridium difficile (C. diff.).
Ongoing projects are applying these earlier findings to common foodborne pathogens, such as Listeria monocytogenes and Salmonella typhimurium. Especially important in this work is an understanding of the role of biofilms, which can affect UVGI by absorbing and/or scattering light. Future efforts will focus on further enhancing disinfection using photocatalytic surfaces and other antimicrobial approaches. This work is also guided by computer graphics-based simulation tools that predict UV light intensity on 3D surfaces. Ultimately, our research will help optimize UVGI protocols, ensure that critical surfaces are adequately disinfected, and improve the design of these facilities.