The medical-supply shortage during the COVID-19 pandemic has created an unprecedented need for disinfecting medical personal protective equipment (PPE). Microwaves and plasma can effectively inactivate microbial pathogens and may be used for disinfecting contaminated medical equipment. This research project presents an exploratory approach to address some of the challenges created by the current pandemic. The researchers will investigate the effectiveness of the dual action of microwaves and plasma in disinfecting PPE contaminated with enveloped viruses, such as the COVID-19, at low temperatures. If successful, this process will have the ability to decontaminate heat-sensitive materials (e.g., masks, gloves, and gowns) by subjecting them to microwave-assisted low-temperature plasma with controlled intensity and density to avoid compromising their structural integrity. The proposed disinfection approach is potentially transformative and may also inspire fundamental changes in how communities use and recycle certain objects, as well as address challenges beyond the current COVID-19 pandemic. For instance, the U.S. Centers for Disease Control and Prevention (CDC) estimates that each year healthcare-associated infections kill more people worldwide than other incidents such as AIDS, breast cancer, or car accidents. The outcomes of the proposed research will significantly contribute to alleviating this problem by presenting effective techniques for disinfecting medical equipment. Thus, it will have tremendous environmental and economic impacts to geographical locations with limited consistent access to fresh medical supplies, e.g., rural communities in the U.S. and other developing countries.
This multidisciplinary research will analyze key parameters affecting microwave and plasma disinfection mechanisms of contaminated PPE at low and nondestructive temperatures. Numerical solutions for equations describing electromagnetic-wave and plasma interactions in an overmoded microwave cavity will be developed. These solutions will be used to design an experimental system to apply variable intensities of microwaves and low-temperature plasma to contaminated specimens. An optimized system will be built with high precision to analyze the parameters affecting the decontamination process. The effectiveness of the developed system in inactivating enveloped viruses, such as COVID-19, will be tested using influenza A viruses. The effective destruction of influenza A virus would guarantee the system's capability to destroy COVID-19. The microwave and plasma intensities and exposure time will be varied while the specimen's temperature, humidity in the device chamber, and the viability of the virus are being monitored. The aim is to determine the effective combination of microwave and plasma doses, exposure time, humidity, and temperature that can destroy the virus. The proposed approach has several advantages over conventional disinfection approaches using chemicals, including speed, convenience for repeated use, continuous availability, environmental friendliness, and safety. The research can potentially be extended to explore disinfecting objects contaminated with other pathogens such as fungal cells and bacteria, in addition to enveloped and non-enveloped viruses.
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.
