Biodegradable, Breathable, and Skin‐Friendly Solution‐Blown Quercetin Nanofibers for Antiviral Nonwoven Filter

ABSTRACT Recent global viral outbreaks have highlighted the urgent need for protective face masks that combine high filtration performance with environmental sustainability. Herein, we developed a biodegradable, breathable, and antiviral nanofiber (NF) filter composed of quercetin (QU) and poly(ethylene oxide) (PEO) via a solution‐blowing (SB) technique. The resulting QU/PEO NF filter exhibited a non‐woven morphology with high porosity and excellent mechanical durability, showing a high yield strength of 30 MPa. It also demonstrated rapid biodegradation in soil, confirming its eco‐friendly nature. Filtration tests showed a high particulate matter (PM 0.5 ) removal efficiency of up to 96.2% at an airflow rate of 20 L/min, with a low pressure drop, outperforming commercial mask filters. Antiviral evaluation showed significant suppression of SARS‐CoV‐2 pseudo‐virus (PV) infectivity with reduced oxidative stress and inflammatory responses in skin cells. Sustained QU release at biologically relevant concentrations established a direct link between intrinsic bioactivity and filter‐level functional performance. In particular, the QU/PEO NF filter demonstrated significant antiviral activity against the live SARS‐CoV‐2 Omicron variant. Molecular docking analyses revealed that QU may engage both 3CLpro and the ACE2 interface, suggesting a potential dual‐target antiviral mechanism. These results demonstrate the strong potential of the QU/PEO NF filter as a next‐generation non‐woven material for personal protective equipment, requiring effective viral protection, excellent breathability, skin compatibility, and environmental sustainability. image