This paper illustrates the separation of particles in a spiral microchannel based on inertial forces and differential migration. This passive microfluidic device can deliver the separation of particles based on their sizes. It is made of four loops with an initial radius of curvature of 2 cm, a channel width of 500 μm, and a height of 50 μm. Systematic analysis, the manufacturing process, simulations, and the methodology of this microfluidic system are presented here alongside the experimentation. In order to realize the process theoretically, computer simulations using Comsol Multiphysics 5.0 were done, describing the laminar flow of fluid streaming across the spiral microchannel and the tracing of particles within the flow. The straightforwardness, material, and productivity of this design make it a perfect model for lab-on-a-chip (LOC) or micro-total analysis systems (μTAS), as it allows for continuous separation applications.

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