[en] Constrictions in blood vessels and microfluidic devices can dramatically change the spatial distribution of passing cells or particles and are commonly used in biomedical cell sorting applications. However, the three-dimensional nature of cell focusing in the channel cross-section remains poorly investigated. Here, we explore the cross-sectional distribution of living and rigid red blood cells passing a constricted microfluidic channel by tracking individual cells in multiple layers across the channel depth and across the channel width. While cells are homogeneously distributed in the channel cross-section pre-contraction, we observe a strong geometry-induced focusing towards the four channel faces post-contraction. The magnitude of this cross-sectional focusing effect increases with increasing Reynolds number for both living and rigid red blood cells. We discuss how this non-uniform cell distribution downstream of the contraction results in an apparent double-peaked velocity profile in particle image velocimetry analysis and show that trapping of red blood cells in the recirculation zones of the abrupt construction depends on cell deformability.
Wagner, Christian ; University of Luxembourg > Faculty of Science, Technology and Communication (FSTC) > Physics and Materials Science Research Unit
External co-authors :
yes
Title :
Cross-sectional focusing of red blood cells in a constricted microfluidic channel
Publication date :
2020
Journal title :
SOFT MATTER
ISSN :
1744-683X
Publisher :
Royal Soc Chemistry, Cambridge, Unknown/unspecified
Volume :
16
Issue :
2
Pages :
534-543
Peer reviewed :
Peer reviewed
Funders :
Deutsche ForschungsgemeinschaftGerman Research Foundation (DFG) [DFG FOR 2688 WA 1336/13-1] European Framework 'Horizon 2020' [675115] Volkswagen FoundationVolkswagen [Az: 93839]
Commentary :
The research leading to these results has received funding from the Deutsche Forschungsgemeinschaft DFG FOR 2688 WA 1336/13-1, from the European Framework 'Horizon 2020' under grant agreement number 675115 (RELEVANCE) and from the Volkswagen Foundation (Az: 93839).