Antiviral Electrospun Polyamide Three-Layered Mask Filter Containing Metal Oxide Nanoparticles and Black Seed Oil

Upon the tremendous spread of coronavirus, there is a need to develop biodegradable, multifunctional, antiviral masks that can be safely used without polluting the environment as conventional surgical masks do. In this study, a three-layered mask filter is designed and fabricated. The first two layers contain electrospun polyamide with dispersed nanoparticles (NPs) of TiO₂ and ZnO prepared via breakdown anodization. The third layer is composed of Nigella sativa oil (black seed oil) electrospun with polyamide and blended with chitosan to form an effective antiviral three-layered mask filter. The morphological characterization revealed the nanoscale features of the fabricated nanofibers with the ZnO and TiO₂ NPs being embedded in the polymeric matrix. The specimens showed good wettability, which is necessary for virus attachment and its subsequent decay. The assembled mask has shown very good mechanical properties. The cytotoxicity results revealed that the proposed mask filter has less cytotoxic effect on the A549 cell line than the commercial KN95 mask filter with maintaining a cell viability of 65.3%. The antiviral activity test showed a variable virucidal effect against human adenovirus on A549 cells. The proposed mask showed the highest effect on the virus followed by PA-ZnO and PA-TiO₂ films, which supports the assumption that the used NPs may have broad and promising effects on viruses when combined with the electrospun films.