Differential inertial focusing of particles in curved low-aspect-ratio microchannels

Abstract

Microfluidic-based manipulation of particles is of great interest due to the insight it provides into the physics of hydrodynamic forces. Here, we study a particle-size-dependent phenomenon based on differential inertial focusing that utilizes the flow characteristics of curved, low aspect ratio (channel width» height), microfluidic channels. We report the emergence of two focusing points along the height of the channel (z-plane), where different sized particles are focused and ordered in evenly spaced trains at correspondingly different lateral positions within the channel cross-section.We applied the system for continuous ordering and separation of suspension particles. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.