Antimicrobial effect of silver nanoparticles plated natural zeolite in polyurethane foam
Abstract
In the present study, a new method for the synthesis of the open-cell soft polyurethane foam (PUF) is developed.
Silver nanoparticles are synthesized on the surface of ultrafine grain (100–500 nm) natural zeolite particles and this zeolite
is than placed as a filler in the polyurethane. The Ag content of natural zeolite and PUF is about 5 wt%, and 1500 ppm, respectively.
Most of the zeolite particles are partially or fully covered in the polyurethane cell wall which is favorable for
long-term storage. However, as soon as the foam comes into contact with water or human sweat, the montmorillonite content
of the zeolite swells and breaking through the cell wall of the foam structure. Indeed, particles of the zeolite protrude from
the polyurethane matrix with the nano-silver particles showing a favourable biocide effect. The antibacterial effect of the
natural zeolite containing Ag nanoparticles was examined against Escherichia coli (Gram-negative), and Micrococcus luteus
(Gram-positive) strains in a 24 and 72 h interval. The results show that the natural zeolite containing Ag nanoparticles filler
has an antibacterial effect, especially against Gram-positive bacteria.