Thesis (M.Sc. Chemistry)--University of Waikato, 2008. / Title from PDF cover (viewed August 26, 2008) Includes bibliographical references (p. 160-168)

Thesis (M.S.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains viii, 46 p. : ill. Includes abstract. Includes bibliographical references (p. 45-46).

Thesis (doctoral)--Lund University, 1998. / Added t.p. with thesis statement inserted. Includes bibliographical references.

Thesis (doctoral)--Lund University, 1998. / Added t.p. with thesis statement inserted. Includes bibliographical references.

Thesis (Ph.D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2008. / Committee Chair: Boris Mizaikoff; Committee Member: Andrew Lyon; Committee Member: Ching-Hua Huang; Committee Member: David Collard; Committee Member: Facundo M. Fernandez.

Thesis (Ph. D.)--University of Texas at Austin, 2005. / Vita. Includes bibliographical references.

Nanotechnology has a steadily increasing impact on worldwide research and business activities. This work explores advanced micro/nano patterning approaches for molecular manipulation. The objectives are to (1) build a proper bridge from a few microns to the 100-10 nm range and below as well as to (2) combine “top-down” precise design with the “bottom-up” size scale to create designed surfaces, areas and volumes that can interact with molecules in a designed way. Three studies were designed and studied accordingly. The first investigation demonstrates that “top-down” Inclined Nanoimprinting Lithography (INIL) is able to produce three-dimensional (3-D) nanopatterns of varying heights in a single step. INIL reduces pattern's feature size from microns to nanometers. The degree of resulting nanopattern's asymmetry can be controlled by the magnitude of the inclination angle. Various 3-D nanostructures are successfully demonstrated including nanolines, nanocircles and nanosquares. The underlying INIL mechanism is investigated, which is primarily due to the induced shear force when the inclination angle is not zero. This leads to the anisotropic dewetting of polymer fluid and consequently asymmetric 3D nanopatterns of varying heights. INIL removes the need of preparation of expensive 3D nanotemplates or multiple template-to-substrate alignments. In addition, such 3-D structures are successfully transferred to silicon, silicone rubber and metal gold. INIL enables 3D nano-scale devices including angle-resolved photonic and plasmonic crystals. The second investigation demonstrates the success of “bottom-up” molecular imprinting of X-ray contrast agent iodixanol in polymer matrix. The synthetic tailor-made molecularly imprinted polymers (MIPs) are poly(4-vinylpyridine-co-ethylene glycol dimethacrylate) which possess specific binding sites induced by the template molecules of X-ray contrast agent iodixanol. It leads the feature size reduction from macromolecules to molecular scale. The properly imprinted binding sites also leads MIPs to have improved absorption capacity and efficiency for X-ray contrast agent iodixanol relative to non-imprinted polymers. The best binding capacity achieved from the optimized MIPs was 284 mg/g in aqueous solution, 8.8 times higher than that of the non-imprinted polymers. The best binding capacity obtained in sheep plasma was 232 mg/g, 4.5 times higher than the non-imprinted polymers. The factors that may affect the binding performance of MIPs in aqueous media are studied. The optimized MIPs are encouraging for biomedical implementations including dialysis and nanosensors. The third investigation of nanolithography-based molecular manipulation (NMM) explores a hybrid approach by combining “top-down” electron-beam lithography (EBL) with “bottom-up” surface initiated polymerization (SIP). It reduces the nanopattern's feature size to sub-10 nm and simultaneously tunes its surface chemistry through functional polymer brushes. The process has reduced process complexity and cost. The demonstrated prototype molecular manipulation templates have 3D surface nanostructures with sub-10 nm feature size and anisotropic surface functionalities. They mimic biocatalyst enzymes to “bottom-up” assemble nanoparticle targets at specific locations producing 3D nanostructures in a designated way. Various 3D synthetic nanostructures have been demonstrated including polystyrene “nanomushrooms” “nanospikes”, “nanofibers” and polystyrene-iron oxide “nanoflowers”. Potential applications of these synthetic 3D nanostructures can be improved therapeutic agents. This hybrid strategy realizes the integration of “top-down” design with “bottom-up” molecular scale to create designed nanopatterned surfaces that can interact with molecules in a designated way.

Surface modification is an extensively researched approach in order to overcomethe limitations, and improve the performance of orthopedic and dental implants. It is atthe surface of the implant materials that the initial interactions of tissues or body fluidstake place. Therefore, surface properties of biomaterials are the important factors that cancontrol these biological responses. Molecular imprinting is a surface modificationtechnique that creates specific recognition sites on the surface of biomaterials. Todevelop the recognition sites, a functional monomer is assembled with templatebiomolecule and then crosslinked. After removal of the template, the surface can rebindthe molecules. Therefore, desired reactions can be initiated at the interface between tissueand implants by modifying surfaces to selectively bind certain types of biomolecules,such as proteins. The objective of this project was to observe the potential of molecularimprinting technique for creating biomaterials that can recognize specific biomolecules.Fluorescently labeled lysozyme or RNase A was used as a template biomolecule and theprotein-imprinted scaffolds were fabricated by sol-gel processing. To interpret the densityof binding sites created, the quantity of surface-accessible protein was determined. Theamount of protein available on the surface was proportional to the amount loaded.Protein-imprinted scaffolds were evaluated for their ability to selectively recognize thetemplate biomolecule. Further, for these selectivity studies, a combination of theimprinted protein and a competitor protein were rebound to the polysiloxane scaffolds.The template protein rebound to the surface was measured more than twice as much ascompetitor. These scaffolds were then tested to understand their interaction with cells.The results of DNA and alkaline phosphatase activities indicate that the scaffolds thusdeveloped support growth and adhesion of osteoblastic cells. These initial selectivity andcytocompatibility studies show the potential of molecular-imprinted polysiloxanescaffolds to be used as tissue engineered materials for stable and controlled interactions atthe tissue-implant interface.

Molecular imprinting, a common method used in separations and chromatography to isolate specific molecules via surface binding, has been adapted for applications in biomaterials and related sciences. The objective of this study was to determine the effectiveness of different approaches to molecular imprinting by testing for preferential binding of protein on polysiloxane scaffold surfaces. To test preferential rebinding, the scaffolds were exposed to a mixture of the template protein and a competitor protein with similar size but different chemistry. Lysozyme-imprinted polymers rebound 8.13 0.99% of lysozyme without any competition and 5.1 0.3% of the protein during competition. Lysozyme C peptide was imprinted into polysiloxane scaffolds to investigate the epitope approach to molecular imprinting. Without competition, 8.95 11.53% of the lysozyme preferentially bound to the scaffolds, while under competition 1.85 9.47% bound to the scaffolds. Lastly, bone morphogenetic protein 2 (BMP-2) was imprinted into the polymer scaffolds. Results revealed that BMP-2 imprinted scaffolds bound 10.09 6.625% under noncompetitive conditions and a very small 0.65 4.55% during competition. Trends of preferential binding via peptide imprinting and BMP-2 imprinting can be seen, and show promise in future tissue engineering material applications and biomaterial compatibility.

Thesis (Ph. D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2005. / Weck, Marcus, Committee Member ; Josowicz, Mira, Committee Member ; Janata, Jiri, Committee Member ; Mizaikoff, Boris, Committee Chair ; Huang, Ching-Hua, Committee Member. Includes bibliographical references.