Polymeric liquid crystals are widespread in nature and as synthetic materials. They have interesting optical and mechanical properties that have led to the creation of novel devices throughout the past century from thermometers to thin display panels. In nature, liquid crystal polymers are evident in spider silk and many tissues in our own bodies. This thesis concerns the properties of one such polymer liquid crystal, collagen, and how the structure can be manipulated in important ways. The orientational order of collagen in many human tissues resembles a twisted plywood structure with the order of a chiral nematic liquid crystal but without the fluidity. Collagen fibers direct the cellular deposition of the extracellular matrix during the wound healing process and a fluid liquid crystalline state is hypothesized during tissue morphogenesis. The self-assembly properties of the collagen molecule make it a premier candidate to replicate the organization found in nature. The use of biologically derived polymers as liquid crystalline materials for in vitro material production creates many design possibilities because of the innate cellular response to these materials in vivo. This thesis describes the self-assembly of collagen into two and three-dimensional architectures for directed cell growth.;In the first study, we report the creation of collagen films having a liquid crystalline cholesteric banding structure with an orientation that can be systematically controlled. The liquid crystalline domains are formed when a highly concentrated collagen solution is deposited under hydrodynamic flow and quickly desiccated. Adult human fibroblasts cultured on these substrates orient in the direction of the flow-deposition and filopodia are extended onto individual cholesteric bands. Atomic force microscopy reveals the assembly of 30 nm collagen micro-fibrils into the uniform cholesteric collagen films with a periodic surface relief of 150 nm. This topology is capable of inducing the contact guidance of the adult human fibroblasts. The generation of collagen films with reticular, 'basket-weave', morphology when using lower concentrations is also discussed.;In the second study, we report the creation of oriented collagen gels. Using a flow processing technique, we develop a method for orienting the collagen prior to fiber formation. The orientation of the collagen fibers within the gel is observed using birefringence measurements and correlated to the response of adult human fibroblast cells. These cells respond to the oriented collagen fibers by polarizing their cytoskeleton in the direction of the fiber. The technique creates a simple methodology for the creation of ordered gels for tissue culture and biomedical purposes.;In the final part of this thesis, we study the influence of spatial confinement on the organization of liquid crystalline collagen. We observe the desiccation of highly concentrated solutions of collagen confined to polydimethysiloxane microchannels. A variety of complex orientation patterns are observed and can be controlled by the microchannel geometry. These observations have possible implications in the mechanics of tissue assembly and biomaterial production with new arrangements of collagen.
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