title: Highly selective biomechanical separation of cancer cells from leukocytes using microfluidic ratchets and hydrodynamic concentrator.
abstract: The separation of cells based on their biomechanical properties, such as size and deformability, is important in applications such as the identification of circulating tumor cells, where morphological differences can be used to distinguish target cancer cells from contaminant leukocytes. Existing filtration-based separation processes are limited in their selectivity and their ability to extract the separated cells because of clogging in the filter microstructures. We present a cell separation device consisting of a hydrodynamic concentrator and a microfluidic ratchet mechanism operating in tandem. The hydrodynamic concentrator removes the majority of the fluid and a fraction of leukocytes based on size, while the microfluidic ratchet mechanism separates cancer cells from leukocytes based on a combination of size and deformability. The irreversible ratcheting process enables highly selective separation and robust extraction of separated cells. Using cancer cells spiked into leukocyte suspensions, the complete system demonstrated a yield of 97%, while enriching the concentration of target cancer cells 3000 fold relative to the concentration of leukocytes.
authors.affiliation: Department of Mechanical Engineering, University of British Columbia, 2054-6250 Applied Science Lane, Vancouver, British Columbia, Canada V6T 1Z4.
authors.forename: Bill K
authors.initials: BK
authors.lastname: Lin
authors.affiliation: Department of Mechanical Engineering, University of British Columbia, 2054-6250 Applied Science Lane, Vancouver, British Columbia, Canada V6T 1Z4.
authors.forename: Sarah M
authors.initials: SM
authors.lastname: McFaul
authors.affiliation: Department of Mechanical Engineering, University of British Columbia, 2054-6250 Applied Science Lane, Vancouver, British Columbia, Canada V6T 1Z4.
authors.forename: Chao
authors.initials: C
authors.lastname: Jin
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Level 6, 2775 Laurel Street, Vancouver, British Columbia, Canada V5Z 1M9 ; Vancouver Prostate Centre, Vancouver General Hospital, 2660 Oak Street, Vancouver, British Columbia, Canada V6H 3Z6.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Black
authors.affiliation: Department of Mechanical Engineering, University of British Columbia, 2054-6250 Applied Science Lane, Vancouver, British Columbia, Canada V6T 1Z4 ; Department of Urologic Sciences, University of British Columbia, Level 6, 2775 Laurel Street, Vancouver, British Columbia, Canada V5Z 1M9 ; Vancouver Prostate Centre, Vancouver General Hospital, 2660 Oak Street, Vancouver, British Columbia, Canada V6H 3Z6.
authors.forename: Hongshen
authors.initials: H
authors.lastname: Ma