Fabrication of antimicrobial chitosan/ZnO nanoparticles/lecithin-montmorillonite films for food packaging application

In this study, ZnO nanoparticles (ZnONPs) were loaded on lecithin-montmorillonite (LEC-Mt) and incorporated into chitosan (CS) for purpose of developing novel food packaging films. The performances of CS@ZnONPs/LEC-Mt films were investigated by X-ray diffraction (XRD), Fourier transform infrared spectrum (FTIR), Ultraviolet spectrum (UV), thermogravimetric analysis (TGA), scanning electron microscope (SEM) and energy dispersive X-ray (EDX) spectroscopy. In addition, the water-resistance performance, mechanical properties and antibacterial activity were studied. An appropriate increase of ZnONPs/LEC-Mt contents (3 wt% and below) could achieve a remarkable enhancement in elongation at break (E)and tensile strength (TS). Meanwhile, the moisture vapor transmission rate (MVTR) and moisture content (MC) of the CS@ZnONPs/LEC-Mt films also decreased with the incorporation of ZnONPs/LEC-Mt, which was beneficial for food preservation. CS@ZnONPs/LEC-Mt films manifested lower light transmission, MC (from 35.36% to 26.01%) and MVTR (from 0.2012 g∙m -2 ∙24 h -1 to 0.1717 g∙m -2 ∙24 h -1 ) values than those of CS film. Furthermore, CS@ZnONPs/LEC-Mt films possess a certain antibacterial activity against Escherichia coli and Staphylococcus aureus . Due to its good UV light barrier properties, mechanical properties and antibacterial property, CS@ZnONPs/LEC-Mt films showed its great potential in designing packaging films