Oscillatory inertial focusing in infinite microchannels.

Autor: Mutlu BR; BioMEMS Resource Center, Center for Engineering in Medicine and Surgical Services, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114., Edd JF; BioMEMS Resource Center, Center for Engineering in Medicine and Surgical Services, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114.; Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA 02114., Toner M; BioMEMS Resource Center, Center for Engineering in Medicine and Surgical Services, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114; mtoner@hms.harvard.edu.; Shriners Hospitals for Children, Boston, MA 02114.
Jazyk: angličtina
Zdroj: Proceedings of the National Academy of Sciences of the United States of America [Proc Natl Acad Sci U S A] 2018 Jul 24; Vol. 115 (30), pp. 7682-7687. Date of Electronic Publication: 2018 Jul 10.
DOI: 10.1073/pnas.1721420115
Abstrakt: Inertial microfluidics (i.e., migration and focusing of particles in finite Reynolds number microchannel flows) is a passive, precise, and high-throughput method for microparticle manipulation and sorting. Therefore, it has been utilized in numerous biomedical applications including phenotypic cell screening, blood fractionation, and rare-cell isolation. Nonetheless, the applications of this technology have been limited to larger bioparticles such as blood cells, circulating tumor cells, and stem cells, because smaller particles require drastically longer channels for inertial focusing, which increases the pressure requirement and the footprint of the device to the extent that the system becomes unfeasible. Inertial manipulation of smaller bioparticles such as fungi, bacteria, viruses, and other pathogens or blood components such as platelets and exosomes is of significant interest. Here, we show that using oscillatory microfluidics, inertial focusing in practically "infinite channels" can be achieved, allowing for focusing of micron-scale (i.e. hundreds of nanometers) particles. This method enables manipulation of particles at extremely low particle Reynolds number ( Re p < 0.005) flows that are otherwise unattainable by steady-flow inertial microfluidics (which has been limited to Re p > ∼10 -1 ). Using this technique, we demonstrated that synthetic particles as small as 500 nm and a submicron bacterium, Staphylococcus aureus , can be inertially focused. Furthermore, we characterized the physics of inertial microfluidics in this newly enabled particle size and Re p range using a Peclet-like dimensionless number ( α ). We experimentally observed that α >> 1 is required to overcome diffusion and be able to inertially manipulate particles.
Competing Interests: Conflict of interest statement: The authors have submitted a patent application related to the presented work.
(Copyright © 2018 the Author(s). Published by PNAS.)
Databáze: MEDLINE
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