Development of an engineered face mask with optimized nanoparticle layering for filtration of air pollutants and viral pathogens

Face masks became a critical part of the personal protective equipment for front-line workers and the public during the COVID-19 pandemic. Studies conducted during the pandemic have shown a strong positive correlation between COVID-19 mortality and air pollution. This project's goals are to develop an engineered face mask with an optimized layering of nanoparticles to filter PM2.5 and viral pathogens, that is cost-effective, reusable, and clinically safe. The nanoparticles were selected based on their filtration, virucidal, and non-toxic properties. The experiment was designed with a wind-tunnel using vacuum pumps to simulate human breathing. The results indicate that particle filtration efficiency (PFE), tested with PM2.5 from incense sticks measured by laser particle detectors improved by & AP;100% as compared to uncoated masks. Virus Filtration Efficiency (VFE), tested using nebulized NaCl particles as a virus surrogate, improved by & AP;140% with nanoparticle coatings. The filtration efficiency was independent of the source of PM2.5. The nanoparticle retention efficacy was well within the permissible exposure limits per OSHA standards. An accelerated durability test demonstrated & AP;95% effectiveness maintained over 4 equivalent days of wear. This multi-purpose, reusable mask can be effective in polluted cities, in fire-prone areas and can protect people against the deadly effects of viruses.