Transport of solid particles in microfluidic channels

Transport of particles is commonly encountered in microfluidic channels that deal with solid–liquid two-phase flows in conjunction with particles and cells to focus, separate, sort, extract, and filter them. In particular, there is a resemblance between microscale flows and macroscale flows in the sense that the inertial migration of particles cannot be neglected. Thus, the objective of the present article is to review how studies on the transport of solid particles have evolved from classical fluid dynamics to up-to-date microfluidics in view of measurement techniques, flow characteristics, and applications.

► Studies on lateral migration of microparticles in microfluidic channels are reviewed.
► Measurement techniques remarked range from conventional LDV to digital holography.
► Primary functions of microcapillary-based and chip-based devices are discussed.