Chitosan-based nanocomposite films incorporated with AgNPs/porphyrinic MOFs for killing pathogenic bacteria

Abstract

In this work, a nanocomposite film, designated as CS/PA, was fabricated by integrating chitosan (CS), porphyrinic porous coordination network (PCN), and silver nanoparticles (AgNPs). PCN modified AgNPs was denoted as PCN-AgNPs (PA). The synthesis of PA was verified through transmission electron microscope, Zeta potential, hydrated particle size, element mapping. Furthermore, varying concentrations of PA (0.3 %, 0.4 %, 0.5 %, and 0.6 % w/w) were integrated into the CS matrix to preparate the CS/PA nanocomposite film. The experimental data demonstrated a significant enhancement (p < 0.05) in the tensile strength and elongation at break of the nanocomposite films, while water vapor permeability and water solubility significantly decreased (p < 0.05) as the PA content increased. Additionally, the CS/PA film showed good antibacterial properties against both gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria. Notably, the CS/PA film effectively retarded the spoilage of fresh fish slices. The silver migration from the CS/PA film, measured at 33.02 μg/L, was found to be within the permissible limits set by the USEPA. Consequently, the CS/PA nanocomposite film holds immense promise for applications in food packaging industry.

Keywords: Antibacterial; Chitosan film; Food packaging; Nanocomposite; Pathogenic bacteria.