| This thesis describes the development and optimization of materials using nanoparticles and self-assembly. Novel nanoparticles have been prepared by electroplating metals into the nanometer-scale pores of alumina and polycarbonate membranes. The resulting nanoparticles have tunable dimensions making them excellent tools for bridging the size gap between molecules and lithographically fabricated features. The electronic properties of these nanoparticles suggest they can act as nanowires allowing them to be used as wiring in nanoscale circuitry.; These nanowires were prepared using a template replication process that enables the nanowires to contain stripes of different materials along their length. Orthogonal derivatization of these segments allows them to be selectively functionalized. This functionalization process introduces the possibility of self-assembling complex nanostructures from these nanowires, and due to the striping of the nanowires, more complex architectures can be assembled using these novel particles as building blocks than can be assembled using spherical or rod-shaped nanoparticles of uniform composition.; This derivatization process was extended to include functionalizing these nanoparticles with DNA oligonucleotides. DNA is an excellent tool for self-assembling because of its selectivity, versatility, and reversibility. To date, Au nanowires have been self-assembled on Au films, lithographically defined Au pads, and in solution. Striped nanowires have been selectively derivatized with oligonucleotides and assembled into crosses, triangles, and t-shapes in solution. These experiments suggest that DNA has an unprecedented ability to assemble these nanowires into functional nanostructures, but aggregation of the nanowires is a competitive process with self-assembly,; To overcome this limitation, work is underway to isolate these DNA-functionalized nanowires at the aqueous/aqueous interface that can be created by mixing two high molecular weight polymers. Isolation at the interface traps the nanowires in two dimensions, limiting their nonspecific interactions. Experiments show that these nanowires are stable at these interfaces over a variety of conditions, and the presence of the polymers impacts DNA hybridization in a predictable fashion. |
