ON THE SLIDING PRINCIPLE OF MICROFLUIDIC DEVICES FOR A POTENTIAL USE IN SORTING CELLS OF DIFFERENT SIZES WITH ONE DEVICE
Date
2018-12-19
Journal Title
Journal ISSN
Volume Title
Publisher
ORCID
0000-0001-5300-3078
Type
Thesis
Degree Level
Masters
Abstract
In recent times, numerous microfluidic devices have been developed to assist in cell analysis both in research and clinical units. Different microfluidic devices capable of capturing, isolating, positioning and sorting single cells have been developed. However, these devices are incapable of working with cells of different sizes; in particular, one device can only work for cells of one size. This problem was addressed in literature with the concept called adaptable or tunable device. Such a device can capture and sort single cells of different sizes, ranging from 20 to 30 µm, due to the inherent limitation of the working principle behind such a device (i.e., deformation-based adjustment of the geometry of the device). On the other hand, in many applications, the desired size range is expected from 2 μm to 100 μm or more.
This thesis first conducted an analysis of different working principles of devices for capturing and sorting single cells, attempting a solution to the problem. As a result, this thesis proposed a novel principle for devices to perform sorting single cells with the cell size ranging from 2 μm to 100 μm, and this principle is named “sliding principle”. To prove the sliding principle to work, a device that contains a micro-trapper or well based on this principle was designed and fabricated using soft lithography with the mold fabricated with a 3D printing technology. The experiment conducted with the microscopy (resolution: 1-3 micron) and motion stage (resolution: 1 micron), which shows that the device can adjust the size of the well trapper, ranging from 0 to 1000 µm and covering the desired cell size range (i.e., 2 μm to 100 μm). According to the current literature on the mechanical approach to capture and sort single cells of different sizes with one device, the device built based on the sliding principle should potentially be applicable to capturing and sorting single cells of different sizes with one device.
This study has a few limitations: (1) the accuracy of the device is not good enough due to the interaction of the PDMS membrane and the model; (2) the inlet and outlet for fluids were not taken in the scope of this research owing to the difficulty of getting proper microspheres or cells for subsequent directing testing on the device. However, the outcome of the present study has paved the way for future research to overcome the preceding limitations.
The main contribution of this thesis is the provision of a new design concept, namely “sliding principle” in the field of micro-fluidic system, for tunable or flexible micro-fluidic devices for a potential application in the tasks such as capturing and sorting single cells of different sizes. In a long run, the sliding principle is a first step towards a new approach to micro-fluidic systems called “robotic micro-fluidic systems”, which adds intelligence to a microfluidic system.
Description
Keywords
Microfluidics, Sorting, silding
Citation
Degree
Master of Science (M.Sc.)
Department
Biomedical Engineering
Program
Biomedical Engineering