Inertial Microfluidics: High-throughput Focusing and Separation of Cells and Particles

Here we describe a continuous particle focusing and separation system taking advantage of microscale physics but with throughput comparable to macroscale systems. The device simply consists of a single asymmetrically curved channel with tuned dimensions and flow conditions. Unlike mechanical filters, deformable and rigid particles are shown to focus and separate with equal efficiency. Additionally, unlike centrifugation the physical mechanism appears independent of particle buoyancy, decoupling separations based on size from density. The described system, able to process large volumes (~ 1 mL/min, 1% w/v particles) in a small footprint (2.5 cm) is expected to be useful for a range of applications in which particles of mixed densities must be separated by size, particles are deformable or rigid, and/or large samples must be processed quickly, such as clinical blood cell sorting.