Modification of face masks with zeolite imidazolate framework-8: A tool for hindering the spread of COVID-19 infection

The worldwide spread of the SARS-CoV-2 virus has continued to accelerate, putting a considerable burden on public health, safety, and the global economy. Taking into consideration that the main route of virus transmission is via respiratory particles, the face mask represents a simple and efficient barrier between potentially infected and healthy individuals, thus reducing transmissibility per contact by reducing transmission of infected respiratory particles. However, long-term usage of a face mask leads to the accumulation of significant amounts of different pathogens and viruses onto the surface of the mask and can result in dangerous bacterial and viral co-infections. Zeolite imidazolate framework-8 (ZIF-8) has recently emerged as an efficient water-stable photocatalyst capable of generating reactive oxygen species under light irradiation destroying dangerous microbial pathogens. The present study investigates the potential of using ZIF-8 as a coating for face masks to prevent the adherence of microbial/viral entities. The results show that after 2 h of UV irradiation, a polypropylene mask coated with ZIF-8 nanostructures is capable of eliminating S. Aureus and bacteriophage MS2 with 99.99% and 95.4% efficiencies, respectively. Furthermore, low-pathogenic HCoV-OC43 coronavirus was eliminated by a ZIF-8-modified mask with 100% efficiency already after 1 h of UV irradiation. As bacteriophage MS2 and HCoV-OC43 coronavirus are commonly used surrogates of the SARS-CoV-2 virus, the revealed antiviral properties of ZIF-8 can represent an important step in designing efficient protective equipment for controlling and fighting the current COVID-19 pandemic.