Whey Proteins–Zinc Oxide Bionanocomposite as Antibacterial Films

• Main Authors: Paolo Pino, Silvia Ronchetti, Chiara Mollea, Marco Sangermano, Barbara Onida, Francesca Bosco
• Format: Article
• Language: English
• Published: MDPI AG 2021-09-01
• Series: Pharmaceutics
• Subjects: nanocomposite; antibacterial; wound dressing
• Online Access: https://www.mdpi.com/1999-4923/13/9/1426

The use of toxic crosslinking agents and reagents in the fabrication of hydrogels is a frequent issue which is particularly concerning for biomedical or food packaging applications. In this study, novel antibacterial bionanocomposite films were obtained through a simple solvent casting technique without using any crosslinking substance. Films were made from a flexible and transparent whey protein matrix containing zinc oxide nanoparticles synthesised via a wet chemical precipitation route. The physicochemical and functional properties of the ZnO nanoparticles and of the composite films were characterised, and their antibacterial activity was tested against <i>S. epidermidis</i> and <i>E. coli</i>. The synthesised ZnO nanoparticles had an average size of about 30 nm and a specific surface area of 49.5 m²/g. The swelling ratio of the bionanocomposite films increased at basic pH, which is an appealing feature in relation to the absorption of chronic wound exudate. A n-ZnO concentration-dependent antibacterial effect was observed for composite films. In particular, marked antibacterial activity was observed against <i>S. epidermidis.</i> Overall, these findings suggest that this novel material can be a promising and sustainable alternative in the design of advanced solutions for wound dressing or food packaging.