Continuous sorting of heterogeneous-sized embryoid bodies

Mechanical and Aerospace Engineering Department, University of California, Los Angeles, CA, USA.
Lab on a Chip (Impact Factor: 6.12). 04/2010; 10(13):1678-82. DOI: 10.1039/c000163e
Source: PubMed


This paper presents a microfluidic device for sorting embryoid bodies (EBs) with large dynamic size ranges up to 300 microm. The proposed separation scheme utilizes appropriately spaced pillars within a microchannel to alter the fluid flow pathway, thus allowing particles of defined sizes to be diverted towards specific flow paths. We test the device functionality by separating polystyrene beads 90, 175 and 275 microm in diameter, demonstrating separation efficiencies approaching 100%. We then demonstrate for the first time on-chip separation of mouse EBs, which were separated into three size groups. The ability to extract specific size ranges of EBs will greatly facilitate their subsequent differentiation studies.

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