The interaction of DNA with nano-structured beta -gallia rutile intergrowths

The demand for viable methods in fabricate nano-devices has driven research into the realm of molecular self-assembly. This thesis outlines a procedure to synthesize beta-gallia rutile (BGR) substrates capable of preferentially binding DNA molecules. The information provided serves as a basis to direct future research toward the patterning of BGR surfaces to facilitate self-assembled DNA nano-constructs. The ability to tailor the separation and orientation of preferentially binding {210}r intergrowth boundaries could enable BUR surfaces to be used as nano-assembling substrates to benefit nano-biologic, electronic and mechanical technologies.;This research initially focused on a sol gel method to apply thin films of Ga2O3 to single-crystal [001] oriented TiO2 substrates. The thermal treatments were systematically studied to obtain a better understanding of how time and temperature influence the formation of the intergrowth structure. Atomic force microscopy (AFM) was used to observe the alignment of the synthesized intergrowth regions.;A 100bp-ladder DNA solution was applied to BGR and bare [001]-oriented rutile substrates. The surfaces were investigated with tapping mode AFM. It was identified from the generated images that DNA deposition solutions containing 1.0 mM additions of select divalent chlorides facilitated the preferential attachment of DNA along {210}r intergrowth regions of BGR surfaces. The large deviations within recorded DNA densities and binding preferences were attributed primarily to the effect of DNA solution aging.;Investigations involving mono-sized, 1000 bp DNA solutions were conducted to determine the influence that cation concentration and DNA solution age had on DNA attachment. Evaluating the density of bound DNA molecules and their end-to-end distances led to insights into the binding behavior. For each cation species and concentration tested, the greatest DNA density was observed at a cation concentration of 1.0 mM; further additions in salt concentration led to decreases in DNA density. Results of bound DNA end-to-end distances reveal that the binding strength of DNA molecules had increased with increasing cation concentration. The results of this research provide increased knowledge about the interaction of DNA with oxide surfaces and may influence the development of new molecular electronic devices.