Novel LDPE/vermiculite/ciclopiroxolamine hybrid nanocomposites: Structure, surface properties, and antifungal activity

The increasing number of indwelling medical materials and devices are connected with infections caused by yeast, especially Candida albicans. This pathogen produces biofilms on synthetic materials, which facilitates adhesion of the organisms to devices and renders them relatively refractory to medical therapy. Since antimicrobial polymer nanocomposites present one of the promising possibilities, this study explores a new approach to achieving this goal by developing nanocomposite based on low density polyethylene (LDPE) with clay mineral vermiculite as an active carrier for antifungal compound. The set of LDPE/clay nanocomposite with increasing amount of antifungal nanofiller was prepared by melt compounding procedure. As antifungal agent was selected generally used active substance ciclopiroxolamine and this compound was loaded into natural vermiculite through ultrasound technique. The structure of all prepared samples was studied by X-ray diffraction analysis and Fourier transforms infrared spectroscopy. Further thermal properties of polyethylene/clay nanocomposites were investigated by thermogravimetric analysis and the surface properties were evaluated by light optical microscopy, scanning electron microscopy and atomic force microscopy. From mentioned characteristics, we conclude that presence of nanofiller in LDPE primarily causes shift of thermal degradation to higher temperatures and increasing of microhardness. All prepared LDPE nanocomposites possess an excellent and prolonged antifungal activity against Candida albicans.