Abstract
This thesis contributes to apply microfluidic technique on cell patterning of tissue engineering. We fabricate two kinds of cell scaffolds in different ways. The first scaffold is fabricated by polymer molding. We induce the magnetic hydrodynamic instability and fission of ferrofluid droplets to generate ordered droplet arrays to be the masters for polymeric mother mold fabrication. Then we use the fabricated mother molds to molding PDMS scaffolds in shape of cones stand on a flat surface, and the bottom flats are the cell patterning regions. Due to the height difference between cone top and bottom flat is very large and the cone side is very steep, we can easily obtain high cell patterning rate (approximately 100%) by using this kind of cell scaffold. The second kind of cell scaffold is fabricated by using microchannel systems. We use T-shaped microchannels to induce the break of viscous shear between UV-light curable agent and immiscible background fluid to generating UV-light curable droplets, and cure the collection of these droplets to fabricate polymeric cell scaffolds. In this way we can generate numerous sized UV-light curable droplets by controlling the flow rate of fluids, and the droplet size is pretty uniform at each selected fluid flow rate. The minimal deviation of the droplet diameter is found as small as 1.7%. In addition to controlling the fluid flow rate, adjusting the UV curing parameter is another way to fabricate types of cell scaffolds. Including honeycomb- and bamboo-like shaped scaffolds are fabricated. In our experiment results, we successfully pattern and culture cells on honeycomb scaffolds, and the best patterning rate is as high as 94.8%. We believe our proposed methods will benefit the research of cell patterning and tissue engineering.