Year: 2016
Type: dissertation
Abstract: Three-dimensional (3D) scaffolds that recapitulate the mammalian extracellular matrix (ECM) have potential applications as tissue engineering scaffolds and as in vitro cell culture material. This thesis describes the fabrication and characterization of microgels, aerogels, hydrogels, and foams that are biomimetics of the natural ECM. The ability to tune the mechanical property and structure of the resulting scaffolds is of particular importance. In Chapter 3, we explore a microfluidic platform for making biopolymer composite microgels in which the rigidity and structure can be tuned in high-throughput manner. Chapter 4 describes how cellulose nanocrystals can be used to make nanofibrillar hydrogels, in which the rheological properties and pore sizes can be controlled by the addition of inorganic salts. These properties are highly dependent on the size, charge, and concentration of the cations added. Chapter 5 describes the freeze-casting of aldehyde-functionalized cellulose nanocrystals and hydrazide-functionalized poly(oligoethylene glycol methacrylate) into anisotropic composite aerogels and their corresponding hydrogels. The aerogel structure could be tuned from fibrillar to columnar and lamellar by varying the freeze-cast composition. The Youngâ s modulus and swelling of the hydrogels differed parallel and perpendicular to the freeze-cast direction. Chapter 6 describes the freeze-casting of polyurethanes into anisotropic open-cell foams, which have anisotropic mechanical and thermal properties. The thermal conductivity of these foams could also be switched between anisotropic and isotropic modes.
Source: TSpace (University of Toronto)
Author: Mo Kit Chau
Language: English
Subfield: Biomaterials
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2943383111