###### Abstract  
Bacterial protein toxins secreted by foodborne pathogens, such as _Staphylococcus aureus_ and Shiga toxin-producing _Escherichia coli_ (STEC) strains, may cause severe toxicosis in humans if present in foods or water and constitute an important public health problem. These toxins are large biomolecules with negative and positive ions due to the ionizable groups in the residual amino acids. An innovative theoretical model of purifying aqueous flowing solutions from ionic toxins is proposed in this study. The principle of the model is based on the drift of the ionic toxins, under the application of the external electric field, towards the walls of the duct, leaving the largest part of the duct with reduced levels of toxin. Parameters, such as toxin concentration, potential and electric field intensity distributions, and surface charge densities, are studied analytically for various duct widths and various external electric fields. The proposed model succeeded to reduce toxin levels by more than 99%, for duct widths less than 1 cm, making it suitable for small-scale water purification. ion drift; electric field; staphylococcal toxin; Shiga toxin (Stc2) Article  
Electric Field Induced Drift of Bacterial Protein Toxins of Foodborne Pathogens _Staphylococcus aureus_ 1  
important category of staphylococcal protein toxins are the hemolysis which cause the lysis of red blood cells. The most common hemolysis is Hla (\(\alpha\) hemolysis) which has a beta-barrel structure that attaches to the cell membrane and disrupts it by forming pores, causing osmotic changes that result in apoptotic cell-death [2; 9]. Apart from the well-known protein toxins of _Staphylococcus_, many other bacterial toxins have been characterized in recent years such as the toxins produced by the gram-negative bacterium _Escherichia coli_ O157:H7, which is one of the most pathogenic serotypes of the common foodborne pathogen _E. coli_. These virulent strains of _E. coli_ are called Shiga toxin producing _E. coli_ (STEC) because they secrete a potent exotoxin called Shiga toxin (Stx) that destroys host cells by inhibiting protein synthesis [10; 11]. Shiga toxins are found in two similar forms, Stx1 and Stx2, with Stx2 being far more virulent in vivo in humans than Stx1, resulting in cases of fatal disease such as the hemolytic uremic syndrome [12; 13; 14]. Stx protein, like other bacterial toxins, has a structure consisting of two subunits, an A-subunit that is surrounded by a ring of five identical B- subunits (AB\({}_{5}\)) [15]. Electric field induced drift method has been successfully applied for water desalination and purification from heavy metals [16; 17; 18]. A similar analysis in nanochannels [19; 20; 21] with the use of molecular analysis simulation showed that this method can successfully drift ions. A prerequisite of this method is that the molecules to be removed should have electric charge, so that in the presence of an electric field they are forced to migrate towards a specific pole. According to the method, the aqueous solution containing the ions flow inside the duct of the applied electric field. Therefore, ions are forced to migrate towards a specific pole of the electric field, and this drift results in decreasing their concentration in the largest part of the duct. In this study, an attempt was made to develop a theoretical model through the application of electric field drift in order to reduce the bacterial toxin load from aquatic environments. Four bacterial protein toxins were selected: three toxins of _S. aureus_ (alphahemolysin, TSST-1, enterotoxin A) and one of _E. coli_ (Shiga toxin Stx2). Furthermore, in order to construct the model, the device used to induce the electric field drift was described and parameters, such as the final spatial distribution of the concentration, electric field intensity, surface charge density, and potential, were calculated for low voltage.