Microfluidic device for measuring the deformability of single cells

• Main Author: Guo, Quan
• Language: English
• Published: University of British Columbia 2012
• Online Access: http://hdl.handle.net/2429/42096

The deformability of single cells can be used as a biomarker to evaluate the status of many diseases including cancer, malaria, and arthritis. Traditional techniques for measuring single cell deformability, such as micropipette aspiration, optical tweezers, and atomic force microscopy, involve delicate experiments performed by highly-skilled technicians using specialized equipment. This thesis presents a new mechanism for measuring the deformability of single cell using the pressure required to deform single cells through a micro-scale constriction. This technique is in principle similar to the micropipette aspiration, but involves considerably simpler operation, is less prone to errors, and requires less specialized equipment and technical skill. The ability of this mechanism to measure single cell deformability is initially verified by testing neutrophils, which demonstrated similar results and measurement precision as micropipette aspiration. Subsequently, this device was used to study the deformability of human red blood cells and specifically, the decrease in deformability of red blood cells parasitized by Plasmodium falciparum, the most common species of the parasite that causes malaria. Finally, this device was used to measure the directional asymmetry associated with the deformation of single cells along the direction of the funnel taper and against the direction of the funnel taper. This asymmetry was used to create a microfluidic ratchet to enable unidirectional transport of cells from a fluctuating fluid flow.