Influence of different concentrations of Zn-carbonate phase on physical-chemical properties of antimicrobial agar composite films

Abstract

Agar-based composites with different Zn-carbonate mineral phase content were prepared by in situ mineralization and the solvent casting method. The mineral phase within the composite films was identified as hydrozincite, Zn-5(CO3)(2)(OH)(6). The presence of the mineral phase improved, both mechanical and water vapor permeability properties of the obtained composite films, in a concentration-dependent manner. The release of zinc ions from composite films is in accepted levels (up to 2.5%), and sufficient to provide complete inhibition growth of S. Aureus. The results of this study suggest that agar/Zn-carbonate composites could be potentially used as affordable, eco-friendly and functional materials with tunable properties for food packaging, agriculture or biomedical application. In situ procedure offers possibilities for tailoring the physical-chemical properties of composite films, by varying the Zn-mineral phase load.