Development of silver nanoparticles infiltrated PLA films for food packaging

Biodegradable polymers are substitutes for non-biodegradable polymers manufactured from fossil fuels to reduce plastic waste. Polylactic acid is a promising candidate for biodegradable polymers. Antimicrobial agents such as silver and copper are added to polylactic acid to improve its antimicrobial properties for food packaging applications. In this work, silver nanoparticles were infiltrated into the polylactic acid matrix to form composite films. The presence of silver nanoparticles has enhanced antimicrobial resistance with attested its suitability to be explored like food packaging film. Additionally, the nanoparticle composite film was to be non-toxic and to have high durability. The properties of polylactic acid/silver nanoparticle films were studied as a function of the silver nanoparticle's weight percentage (0%, 5% and 10%). The incorporation of silver nanoparticles in the polylactic acid matrix was established by Fourier transform infrared spectroscopy spectrometer, ultraviolet-visible spectrometer, and field emission-scanning electron microscopy. Fourier transform infrared spectroscopy and ultraviolet-visible spectrum suggest the presence of silver nanoparticles in the composite films. Thermal gravimetric analysis and differential calorimeter analysis reveal the change in degradation and glass transition temperature with an increase in silver nanoparticle concentration. The antibacterial property using the disk diffusion method indicates that polylactic acid/silver nanoparticles (10%) had the highest antibacterial property. Antibacterial action is enhanced when silver nanoparticles are combined with a tiny dose of antibiotics, especially when battling multi-strain-resistant bacteria.

Graphical Abstract

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