Dielectrophoretic characterization and trapping of different waterborne pathogen in continuous flow manner

Abstract This paper presents a microfluidic device which traps and characterizes different neutral particles. Neutral particles include polystyrene bead and cells. The microfluidic device was fabricated utilizing the conventional microfabrication technique and was used to characterize the dielectrophoretic trapping behavior of different neutral particles. The trapping efficiency of this microfluidic device was evaluated too. The trapping behavior between non-living microorganism (polystyrene bead) and living microorganism (bacteria) were studied and compared and the separation between these two different neutral particles was achieved using this microfluidic device. In this project, two types of bacterial species from two major classifications of bacteria were prepared and cultured. They were Escherichia coli (Gram-negative bacteria) and Enterococcus faecalis (Gram-positive bacteria). The main difference between these two bacteria is their cell wall structure, and this may cause the effective dielectric properties to be slightly different. Different experiment conditions and parameters were applied into the experiment in order to study the differences in their dielectrophoretic behavior and hence to investigate if there were any differences in dielectrophoretic force experienced by both species.