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Title: Enhancing stiffness-based cell sorting using power-law fluids in ridged microchannels
Sorting biological cells in heterogeneous cell populations is a critical task required in a variety of biomedical applications and therapeutics. Microfluidic methods are a promising pathway toward establishing label-free sorting based on cell intrinsic biophysical properties, such as cell size and compliance. Experiments and numerical studies show that microchannels decorated with diagonal ridges can be used to separate cell by stiffness in a Newtonian fluid. Here, we use computational modeling to probe stiffness-based cell sorting in ridged microchannels with a power-law shear thinning fluid. We consider compliant cells with a range of elasticities and examine the effects of ridge geometry on cell trajectories in microchannel with shear thinning fluid. The results reveal that shear thinning fluids can significantly enhance the resolution of stiffness-based cell sorting compared to Newtonian fluids. We explain the mechanism leading to the enhanced sorting in terms of hydrodynamic forces acting on cells during their interactions with the microchannel ridges.  more » « less
Award ID(s):
1928262
PAR ID:
10574836
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
AIP Publishing
Date Published:
Journal Name:
Physics of Fluids
Volume:
35
Issue:
4
ISSN:
1070-6631
Page Range / eLocation ID:
043327
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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