Development of an activated carbon-based nanocomposite film with antibacterial property for smart food packaging

This work is to develop silver integrated nanocomposite film based on activated carbon (AC) and cellulose nanofiber (CNF) and characterize its functional properties for smart food packaging. The nanocomposite film was produced using a casting method, which used the ultrasonic suspension of CNF impregnated with AC and silver nanoparticles (AgNPs), named activated carbon-based silver-cellulose film (AgNPs/AC-CNF). The anti-microbial properties of the film were tested against food pathogens, Staphylococcus aureus and Escherichia coli. It was found that AgNPs concentrations in the range of 140-450 ppm inhibited the growth of S. aureus and E. coli on the agar plates. The conductivity of AgNPs/AC-CNF film was also examined for its cyclic voltammetry (CV), differential plus voltammetry (DPV) and linear sweep voltammetry (LSV) using a potentiostat. The results obtained by CV and DPV showed that peak current increased from 0.2 to 1.1 mu A and 0.78 to 1.16 mu A, respectively. The electrical resistivity of the film decreased from 6.8 to 1.9 k Omega.cm as AgNPs increased over the range of 70 to 450 ppm. Transmission electron microscopy (TEM) analysis of the film showed that AgNPs were dispersed evenly within the film and well-connected with the pores of CNF and AC particles. This AgNPs/AC-CNF film showed promise to be an effective antimicrobial conductive film for smart food packaging applications.