Cold-plasma surface engineering induces multifunctional enhancements in biodegradable packaging films

Biodegradable packaging materials made from polysaccharides, proteins, and other biobased polymers offer environmental benefits over synthetic plastics but often suffer from poor mechanical strength, water sensitivity, and weak barrier properties. These limitations hinder their broader adoption in food packaging applications. Cold plasma (CP), a non-thermal and solvent-free surface engineering technique, has emerged as a promising solution to enhance the functionality of biodegradable films without affecting their bulk characteristics. This review summarizes recent developments in CP technology for modifying biodegradable packaging materials. Key focus areas include plasma-induced changes in surface chemistry, wettability, and interfacial properties, as well as CP-assisted coating strategies and nanoparticle integration. CP treatment introduces reactive species that etch and functionalize polymer surfaces, increasing surface roughness and incorporating polar groups. These modifications can improve wettability, coating adhesion, and compatibility with active agents. CP also enhances tensile strength, thermal stability, and barrier performance under optimized conditions. Moreover, it enables the synthesis and functionalization of nanomaterials, such as nanocellulose, starch, and protein-based nanoparticles, providing additional reinforcement and functionality to packaging films. Plasma-treated films have shown improved antimicrobial performance, particularly when combined with essential oils or metallic nanoparticles. While CP offers a green, tunable platform for developing multifunctional packaging systems, challenges related to treatment uniformity, scalability, and material-specific responses remain. Addressing these limitations through process optimization and standardization will be essential to support industrial translation and regulatory approval. • Cold plasma modifies surface properties of biodegradable packaging films. • CP enhances film functionality without altering bulk material properties. • CP boosts adhesion, wettability, and coating stability on polymers. • CP enables nanoparticle synthesis for active and smart packaging films. • Different plasma sources allow customized treatment of biopolymer films.