Design and Development of Robust, Daylight-Activated, and Rechargeable Biocidal Polymeric Films as Promising Active...

The emerging infectious diseases have created one of the major practical needs to develop active packaging materials with durable antibacterial and antiviral properties for the food industry. To meet this demand, the development of new technologies applicable to food contact surfaces is highly desired but challenging. The recent discovery of the photoactive properties of vitamin K (VK) derivatives has raised great expectations as promising candidates in functional film development due to the generation of biocidal reactive oxygen species (ROS) by these compounds. Inspired by the excellent photoactivity of one of the light-stable VK derivatives, menadione (VK3), under visible daylight irradiation, we demonstrate a protocol for the fabrication of daylight-mediated biocidal packaging materials by incorporating VK3 into a poly (ethylene-co-vinyl acetate) (EVA) matrix. The VK3 (i.e., 1-5% w/w) incorporated EVA films successfully demonstrated the production of ROS and antibacterial and antiviral performance against Escherichia coli, Listeria innocua, and T7 bacteriophage, respectively, under daylight exposure conditions. The results revealed that the addition of a proper percentage of VK3 significantly enhanced the ROS productivity of the films and created a novel daylight-induced microbial killing performance on the films. The biocidal functions of the films are long-lasting and rechargeable when exposed to light repeatedly, making them a viable contender for replacing currently available conventional packaging films.