Fabrication of dual-layered microfluidic-blow-spinning nanofiber films with antibacterial and antioxidant functions for food packaging

Abstract Fresh food products are highly susceptible to microbial contamination and oxidative deterioration during storage, necessitating effective preservation strategies. In the present study, we employed a rapid, scalable, and safe microfluidic-blow-spinning technique to develop a novel multifunctional dual-layered nanofiber film featuring asymmetric wettability and antioxidant and antimicrobial properties. The films consisted of a hydrophobic polycaprolactone (PCL)/ethyl cellulose (EC) layer loaded with thymol and a hydrophilic polyurethane (PU)/polyvinylpyrrolidone (PVP) layer loaded with quercetin. The hydrophilic layer exhibited good antioxidant activity comparable with vitamin C, whereas the hydrophobic layer showed effective antibacterial activity against Escherichia coli and Staphylococcus aureus, 92.3% and 98.0%, respectively. In addition, the dual-layered structure significantly improved the elongation at break from 133.28% to 168.81% and improved the thermal stability of the films. The above results indicate that the proposed dual-layered nanofiber film is a promising and sustainable solution for the postharvest preservation of fresh food products.