Deformability based sorting of red blood cells and white blood cells using microfluidic ratchets
department or school: Applied Science, Faculty of
department or school: Mechanical Engineering, Department of
data provider: DSpace
degree campus: UBCV
creator: Guo, Quan
issued: 2016-11-02T00:00:56
issued: 2016
related degree: Doctor of Philosophy - PhD
degree grantor: University of British Columbia
description: There are many situations in medicine and biology where it is desirable to sort cells in a heterogeneous sample based on their mechanical deformability, which can potentially serve as a proxy for morphology or pathology. This biophysical characteristic is particularly relevant for cells in the circulatory system, such as red blood cells and white blood cells, because deformability determines the capacity for these cells to transit through the microvasculature. Since deformability is such a fundamental characteristics of blood cells, deviations in normal cell deformability can contribute to a range of pathological conditions, such as microvascular occlusion, tissue necrosis and organ failure, observed in diseases such as malaria caused by Plasmodium falciparum. A commonly employed approach for deformability-based cell sorting is microfiltration. However, this method suffers from cell clogging at the filter microstructures, leading to reduced selectivity and device malfunction. This dissertation presents an improved microfiltration strategy performed using the microfluidic ratchet mechanism, which relies on the deformation of individual cells through micrometer-scale tapered constrictions. Deforming single cells through such constrictions requires directionally asymmetrical forces, which enables oscillatory flow to create a ratcheting transport that depends on cell size and deformability. Simultaneously, oscillatory flow continuously agitates the cells to limit the contact time with the filter microstructure to prevent clogging and adsorption. This work demonstrates the utility of the ratchet mechanism for cell sorting by developing a microfluidic device to sort red blood cells based on deformability. The device is used to separate Plasmodium falciparum infected red blood cells from uninfected cells. The method was shown to dramatically improve the sensitivity of malaria diagnosis performed using both microscopy and rapid diagnostic tests by converting samples with di…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/59592
note: DEFORMABILITY BASED SORTING OF RED BLOOD CELLS AND WHITE BLOOD CELLS USING MICROFLUIDIC RATCHETS by Quan Guo B.Sc., Zhejiang University, 2009 M.Sc., The University of British Columbia, 2012 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES (Mechanical Engineering) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) October 2016 © Quan Guo, 2016 ii Abstract There are many situations in medicine and biology where it is desirable to sort cells in a heterogeneous sample based on their mechanical deformability, which can potentially serve as a proxy for morphology or pathology. This biophysical characteristic is particularly relevant for cells in the circulatory system, such as red blood cells and white blood cells, because deformability determines the capacity for these cells to transit through the microvasculature. Since deformability is such a fundamental characteristics of blood cells, deviations in normal cell deformability can contribute to a range of pathological conditions, such as microvascular occlusion, tissue necrosis and organ failure, observed in diseases such as malaria caused by Plasmodium falciparum. A commonly employed approach for deformability-based cell sorting is microfiltration. However, this method suffers from cell clogging at the filter microstructures, leading to reduced selectivity and device malfunction. This dissertation presents an improved microfiltration strategy performed using the microfluidic ratchet mechanism, which relies on the deformation of individual cells through micrometer-scale tapered constrictions. Deforming single cells through such constrictions requires directionally asymmetrical forces, which enables oscillatory flow to create a ratcheting transport that depends on cell size and deformability. Simultaneously, oscillatory flow continuously agitates the cells to limit the contact time with the filter microstructure to prevent …
has type: Thesis/Dissertation
date issued: 2017-02
is shown at: 10.14288/1.0320833
language: eng
degree discipline: Mechanical Engineering
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/59592