ABSTRACT
The ongoing COVID-19 pandemic has revealed that developing effective therapeutics against viruses might be outpaced by emerging variants,1-5 waning immunity,6-9 vaccine skepticism/hesitancy,10-12 lack of resources,13-16 and the time needed to develop virus-specific therapeutics,17,18 emphasizing the importance of non-pharmaceutical interventions as the first line of defense against virus outbreaks and pandemics.19-23 However, fighting the spread of airborne viruses has proven extremely challenging,23-28 much more if this needs to be achieved on a global scale and in an environmentally-friendly manner.29,30 Here, we introduce an aerosol filter made of granular material based on whey protein nanofibrils and iron oxyhydroxides nanoparticles. The material is environmentally-friendly, biodegradable, and composed mainly of a dairy industry byproduct.31 It features remarkable filtration efficiencies between 95.91% and 99.99% for both enveloped and non-enveloped viruses, including SARS-CoV-2, the influenza A virus strain H1N1, enterovirus 71, bacteriophage {Phi}6, and bacteriophage MS2. The developed material is safe to handle and recycle, with a simple baking step sufficient to inactivate trapped viruses. The high filtration efficiency, virtually-zero environmental impact, and low cost of the material illuminate a viable role in fighting current and future pandemics on a global scale.