Dielectrophoretic Microfluidic Device for the Separation of Foodborne Bacteria from Blood

The gram-negative Escherichia coli (E-coli) and gram-positive Staphylococcus aureus (S-aureus) bacteria may lead to foodborne diseases if they are allowed to enter the bloodstream. The potential risk of bacteria colonization is expected for the consumers of many food products, such as milk, meat, etc. Hence, the separation of these types of bacteria from blood is pivotal for choosing effective treatments. The present study proposes a dielectrophoretic microfluidic device to isolate E-coli and S-aureus bacteria from blood cells using COMSOL Multiphysics 5.6 software. The results demonstrate that the applied potential and frequency, the distance between electrodes, and the buffer-to-sample inlet velocity ratio affect bacterial capture. The present work concludes that the isolation of bacteria from blood cells using the proposed microchip and studied parameters is practical when the blood behaves as a non-Newtonian fluid. Accordingly, the optimal conditions for the complete separation of E-coli and S-aureus bacteria from blood cells can be achieved for the electrode distance of 60 μm, the potential of 100 V, and the frequency of 0.1 MHz when the buffer-to-sample flow rate is 3.