Preparation of AgNPs/oregano essential oil composite film and its antibacterial application in the conservation of paper relics

Electrospinning technology is an innovative method used to synthesize continuous ultra-fine polymer fibers of nanomaterials, offering a mild processing environment that enables the integration of bioactive substances, metal particles, and polymer matrix materials. Notably, silver nanoparticles (AgNPs) exhibit significant and ecofriendly antibacterial properties, as these small-sized metal nanoparticles can penetrate bacterial cells swiftly and induce quick sterilization. Additionally, oregano essential oil (OEO), extracted from natural plants, is an environmentally safe agent with broad-spectrum antibacterial and strong antioxidant properties. In this study, four types of electrospun membranes were prepared: polyacrylonitrile (PAN) nanofiber membranes, oregano essential oil (OEO) nanofiber membranes, silver nanofiber membranes loaded with oregano essential oil (AgNPs/ OEO), silver nanofiber membranes (AgNPs). To characterize these membranes, their surface morphology, crystalline phase structures, and functional group characteristics were analyzed. The antibacterial effects of these four membranes on rice paper were then investigated through contact and non-contact experiments. Finally, AgNPs/OEO composite film exhibited excellent antifungal effects against Aspergillus niger on rice paper under both conditions and was essentially non-invasive to the paper cultural relic's ontology, offering a new method for the conservation of paper cultural relics.