Polyethylene glycol enhanced encapsulation of thymol in metal-organic framework nanocarriers for antimicrobial food packaging
Yun Zhang, Vittorio Boffa, Peter Roslev, Giuliana Magnacca, Deyong Wang
Abstract
Thymol is a natural and environmentally friendly antibacterial agent. A novel Zirconium-based metal-organic framework (UiO-66) coated with polyethylene glycol (PEG) serves as thymol carrier. This carrier was incorporated into chitosan/polyvinyl alcohol (CS/PVA) films for antimicrobial applications. Characterization showed that PEG was coated on the surface of UiO-66 without disrupting the structure of UiO-66. The coating of PEG prevented the evaporation of thymol before 270 °C and decreased the release rate of thymol with retention of 12.3 %. UiO-66 retained its octahedral structure when combined with CS/PVA films, which was beneficial to the continuous release of thymol. Antimicrobial activity experiments demonstrated that CS/PVA with UiO-66 loaded with thymol had excellent inhibition of E. coli , along with an inhibition zone of 16 mm. Overall, the antimicrobial films developed in this study hold promising potential for applications in the food industry. • Films incorporating metal-organic framework (MOF) loaded with thymol were developed. • Polyethylene glycol (PEG) modification provided a controlled release mechanism. • Films exhibited significant antimicrobial activity against Escherichia coli. • PEG/MOF-encapsulated thymol provided a sustainable active food packaging solution.