We've Moved!
Visit SDSU’s new digital collections website at https://digitalcollections.sdsu.edu
Description
The isolation and capture of rare cells continue to be challenging tasks for researchers. By capturing these rare cells, like cancer stem cells, researchers can further study and understand cancer progression. Micro Electro Mechanicals Systems (MEMS) provides the necessary tool to investigate this issue further. Microfluidic platforms using several techniques have demonstrated the ability to isolate and capture rare cells. In this work, we fabricate a 16-channel microfluidic device using glass substrates. 3D chevron features are incorporated into the channel design to promote micromixing. This project's innovative idea uses glass substrates to fabricate a double-layer device. The isotropic etching properties of glass allow the fabrication of channels with rounded walls, previously impossible or complicated with Polydimethylsiloxane (PDMS) devices. The rounded channel walls allow studying new geometry and aspect ratios to improve rare cell capture efficiency by increasing cell collisions with the walls. Also, one can take advantage of the borosilicate glass mechanical properties to create a more durable device with minimal channel deformation due to pressure. Finite Element Analysis is used to study the flow characteristics and optimize channel design. This research's primary outcome is developing an optimized glass micromachining protocol to fabricate microfluidic devices and produce channels with geometry and aspect ratio (width to depth) not possible with PDMS. The fabrication time decreased approximately 45%, from 370 minutes to 170 minutes. While microfluidic channels with aspect ratios of up to 8.5 were fabricated successfully. Lastly, a flow test was performed on the double-layer glass microfluidic device using a 200 μL per minute flow rate. The results accomplished throughout this thesis demonstrate the potential to improve current microfluidic devices further using glass micromachining.
