ICEK phenomena have recently been used for separating particles. The most critical issue in separating the nanoparticles (e.g., exosome, viruses, or bacteria) in complex biofluids is implementing a two-step procedure (I) trapping the larger particles (e.g., red blood cells) from the blood and (II) trapping the nanoparticles. The purpose of this paper is to propose a design framework for the separation of considered particles in one chip. The model considered evaluating the feasibility of two-step micro and nanoparticle separations, for instance, exosome (30-120 nm) from red blood cells (5-7 μm) or other cells in biological samples. A low voltage direct current (DC) electric field is used to generate vortices around the obstacles to trap microparticles (e.g., red blood cells) and nanoparticles (e.g., exosome) before the first and second obstacles, respectively. The achieved results demonstrated that the generated vortices are adequately strong to trap both micro and nanoparticles. This chip has several advantages, consisting of low voltage requirement and easy to manufacture design.

Bloodstream infections have a high mortality rate with >80,000 deaths per year in North America. The inability to detect pathogens quickly in the early stages of the infection causes high mortality. Such inability has led to a growing interest in developing a rapid, sensitive, and specific method for identifying these pathogens. The rapid detection of bloodstream infections requires the rapid and efficient separation of bacteria from the blood. But the problem is that the number of bacteria is much lower than other blood components. The blood culture step needs to be accomplished first for bacteria identification and antibiotic susceptibility testing. As the blood culture is time‐consuming, a method based on the insulator‐based has been presented that increases the number of bacteria by combining the blood culture method and increasing the concentration. In this model, the dielectrophoresis technique was utilized in a curved microchannel with a constriction for sorting three particle sizes including 9, 7–4 μm, as well as smaller than 3 μm. The results showed that the applied voltage and the channel dimensions affect separation efficiency. Suppose these values are properly selected (for example, a voltage of 110 V that was causing the maximum electric field of 200 V/cm). The proposed model can completely (100%) separate larger than 9 μm and smaller than 3 μm particles. The proposed model has simple geometry and is considered an appropriate technique for sorting all bacteria separation in bloodstream infection.

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