Silver-nanoparticle-impregnated cellulose nanofiber coating for packaging paper

In this study, antimicrobial packaging was prepared by mixing colloidal silver nanoparticles with cellulose nanofiber (CNF) and depositing this hybrid coating (CNF/Ag) as a layer on different paper substrates. The CNF/Ag-coated papers were then characterized by scanning electron microscopy (SEM). In addition, their antimicrobial activity, and barrier and strength properties were assessed. SEM showed deposition of Ag nanoparticles on the surface of CNF and formation of a relatively smooth, dense coating layer on the paper surface. The results also demonstrated that the CNF/Ag coating exhibited good antibacterial activity against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria. Although the coating coverage was influenced by paper surface characteristics and coat weights, almost all properties (except water absorption of greaseproof paper) including the water vapor transmission rate, oil resistance, and tensile strength of the CNF/Ag-coated papers were improved in comparison with uncoated papers.