Portland State University. Department of Mechanical and Materials Engineering
Date of Award
Master of Science (M.S.) in Mechanical Engineering
Mechanical and Materials Engineering
1 online resource (v, 71 p.) : ill. (chiefly col.)
Microfluidics, Chromatographic analysis, Porous materials, Silk
Silk fibroin from silkworm cocoons is found in numerous applications ranging from textiles to medical implants. Its recent adoption as a biomaterial is due to the material's strength, biocompatibility, self-assembling behavior, programmable degradability, optical clarity, and its ability to be functionalized with antibodies and proteins. In the field of bioengineering it has been utilized as a tissue scaffolding, drug delivery system, biosensor, and implantable electrode. This work suggests a new application for porous silk in a microscale chromatography column. We demonstrate in situ cryotropic polymerization of highly porous structures in microscale geometries by freezing aqueous silk with a solvent. The resulting cryogels are experimentally characterized using flow parameters common in chromatography design; tortuosity, global pressure drop, pore diameter, and porosity. These empirical parameters are put into porous flow models to calculate an order-of-magnitude increase in functional surface area over the blank capillaries and packed-sphere columns used in traditional designs. Additionally, the pressure requirements to produce relevant flow rates in these structures are found not to threaten the integrity of microfluidic seals or connectors.
Hinojosa, Christopher David, "Silk Cryogels for Microfluidics" (2012). Dissertations and Theses. Paper 513.