Direct measurement of particle inertial migration in rectangular microchannels. Issue 15 (28th June 2016)

• Record Type: Journal Article
• Authors: Hood, Kaitlyn; Kahkeshani, Soroush; Di Carlo, Dino; Roper, Marcus
• Is Part Of: Lab on a chip. Volume 16:Issue 15(2016)
• Page Start: 2840
• Page End: 2850
• Publication Date: 2016-06-28
• Subjects: Miniature electronic equipment -- Periodicals; Combinatorial chemistry -- Periodicals; Biotechnology -- Periodicals; 543.0813
• DOI: 10.1039/c6lc00314a
• Languages: English
• ISSNs: 1473-0197

Abstract

Abstract : We experimentally measured the trajectories of particles undergoing microfluidic inertial focusing, and show that they can be predicted by an asymptotic theory with no unmeasured parameters. Abstract : Particles traveling at high velocities through microfluidic channels migrate from their starting streamlines due to inertial lift forces. Theories predict different scaling laws for these forces and there is little experimental evidence by which to validate theory. Here we experimentally measure the three dimensional positions and migration velocities of particles. Our experimental method relies on a combination of sub-pixel accurate particle tracking and velocimetric reconstruction of the depth dimension to track thousands of individual particles in three dimensions. We show that there is no simple scaling of inertial forces upon particle size, but that migration velocities agree well with numerical simulations and with a two-term asymptotic theory that contains no unmeasured parameters.