Mussel-inspired chemistry to design biodegradable food packaging films with antimicrobial properties

Environmental pollution owing to plastic waste is a growing global issue. Packaging materials generate the maximum plastic waste, weighing 141 million tonnes/year. Driven in part by pressure from progressively environmental-conscious consumers, many industries are shifting their means of packing food products to more sustainable options. To promote sustainability, the present work investigates the potential of mussel-inspired polydopamine (pDA) chemistry to develop biodegradable antimicrobial food packaging materials. The food packaging films are designed using unique material combinations including polyvinyl alcohol (PVA), pDA, glycerol, and epsilon-polylysine (εPL). Along with exceptional biodegradability (46% in 1 week), these films demonstrate superb antibacterial activity against both gram-positive and gram-negative bacteria, as well as good thermal and mechanical properties. Additionally, these packaging films display excellent UV shielding properties that can protect the food from UV-induced photodegradation. Overall, this study uncovers numerous novel phenomena of mussel-inspired polydopamine chemistry to address major issues with plastic-based food packaging, such as biodegradability, microbial contamination of food, light-induced food spoilage, and so on.