Chapter 13 - Complexes of Metal-Based Nanoparticles with Chitosan Suppressing the Risk of Staphylococcus aureus and Escherichia coli Infections

Abstract

Nanoparticles of metals interacting with cellular components and biomacromolecules including DNA and RNA alter cellular processes. From the point of view of the antimicrobial activity, the metal nanoparticles at nanomolar concentrations exhibit excellent results on the inhibition of bacterial strains. The general mechanism of metal nanoparticles action has not been fully understood yet; however, several currently accepted schemes include damaging of the microbial enzymes by the release of metal ions, changing the integrity of the membrane, penetration into the bacterial cytoplasm, and accumulation in the periplasmic space or the formation of reactive oxygen species by the effect of metal nanoparticles. Moreover, Gram-positive bacteria react significantly later on the effect of metal nanoparticles than Gram-negative bacteria, which is reflected with the later inhibition of cell division. The aim of this study is to describe the properties of metal nanoparticles (silver, selenium, copper, or zinc nanoparticles) and to compare their antimicrobial properties in a complex with chitosan on the bacterial strains Staphylococcus aureus and Escherichia coli.