Composite Films Based on Silver-Zeolite/Polymer as Efficient Antifungals

Abstract

This work analyzes the preparation and antifungal behavior of composite films formed by a mixed matrix of Ag-zeolite crystals immobilized in a continuous polymer phase. The physicochemical qualities of films prepared with Ag-exchanged mordenite (Ag-MOR) dispersed in polysulfone (PSF), polyimide (PI) or polyetherimide (PEI) were thoroughly analyzed by means of various techniques such as SEM, EDS, XRD, UV-VIS, FTIR-ATR, TGA-SDTA and XPS. Subsequently, the composites were evaluated as antifungal materials for the control of P. roqueforti isolated from contaminated foods of industrial origin. Of all the systems studied, Ag-MOR/PI demonstrated an outstanding antifungal activity, acting effectively in the control of this mold and reducing the colony growth (CFU mL−1) by a factor of 5 Log after 24 h of contact. This activity was due to highly dispersed cationic silver species immobilized in the film which were effectively dosed towards the microorganism. The Ag-mordenite/polymer nanocomposite films represent a technological alternative in the search of novel materials for the control of fungal growth.