Particle migration dynamics in viscoelastic fluids in spiral channels have attracted interest in recent years due to
potential applications in the 3D focusing and label-free sorting of particles and cells. Despite a number of recent
studies, the underlying mechanism of Dean-coupled elasto-inertial migration in spiral microchannels is not fully
understood. In this work, for the first time, we experimentally demonstrate the evolution of particle focusing behavior
along a channel downstream length at a high blockage ratio. We found that flow rate, device curvature, and medium
viscosity play important roles in particle lateral migration. Our results illustrate the full focusing pattern along the
downstream channel length, with side-view imaging yielding observations on the vertical migration of focused
streams. Ultimately, we anticipate that these results will offer a useful guide for elasto-inertial microfluidics device
design to improve the efficiency of 3D focusing in cell sorting and cytometry applications.
more »
« less
Evolution of focused streams for viscoelastic flow in spiral microchannels
Particle migration dynamics in viscoelastic fluids in spiral channels have attracted interest in recent years due to potential applications in the 3D focusing and label-free sorting of particles and cells. Despite a number of recent studies, the underlying mechanism of Dean-coupled elasto-inertial migration in spiral microchannels is not fully understood. In this work, for the first time, we experimentally demonstrate the evolution of particle focusing behavior along a channel downstream length at a high blockage ratio. We found that flow rate, device curvature, and medium viscosity play important roles in particle lateral migration. Our results illustrate the full focusing pattern along the downstream channel length, with side-view imaging yielding observations on the vertical migration of focused streams. Ultimately, we anticipate that these results will offer a useful guide for elasto-inertial microfluidics device design to improve the efficiency of 3D focusing in cell sorting and cytometry applications.
more » « less- NSF-PAR ID:
- 10420330
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Microsystems & Nanoengineering
- Volume:
- 9
- Issue:
- 1
- ISSN:
- 2055-7434
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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