Influence of the Staphylococcus Aureus Bacteria Cells on the Zeta Potential of Graphene Oxide Modified with Alumina Nanoparticles in Electrolyte and Drinking Water Environment

The aim of this study was to describe the different aspects of the modification of surface charge of graphene oxide by deposition of Al₂O₃ nanoparticles on its surface. The novel reduced graphene oxide/Al₂O₃ nanocomposites were evaluated as an adsorbent for Staphylococcus aureus bacteria cells in electrolyte and drinking water environment. The zeta potential of GO flakes, Al₂O₃ nanoparticles and RGO/Al₂O₃ nanocomposite was investigated alone and in the presence of bacteria cells with a special emphasis on the analysis of the zeta potential curves. Our obtained results indicate that the chemical composition of water environment have a significant influence on the electrostatic interactions between sorbent and bacteria. In most cases, the adsorption of bacteria onto adsorbent surface changed its surface charge to similar to adsorbed cells. However, by taking into consideration the sensitiveness and variability of living system such as bacteria cell, we observed that the phenomenon of adsorption (i.e. the physical interactions with sorbent surface) also changed the surface charge of bacteria cells themselves.