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The study of biological analytes in their native environment is a major challenge for biochemistry and molecular biology.  Luminesce spectroscopy is well suited for this task due to its non-invasiveness, high spatial and temporal resolution, and high signal to noise ratio. This thesis describes the development and applications of Ln-based luminescent probes for detecting small molecules and enzymes.  Specifically the probes presented are based on coumarin sensitizers coupled to a DO3A chelated LnIII center. The 1st generation of these probes employ 7-OH coumarins, caged at the 7-O position (Chapter 2). By use of p-pinacolatoboron benzyl or p-methoxybenzyl cages, this design allowed the construction of ratiometric EuIII-based probes capable of detecting the reactive oxygen species H2O2, NO and ONOO−. The second and third part of the thesis describes a further improvement of the design (Chapters 3 and 4). By employing caged coumarin precursors EuIII and TbIII-based probes were developed for a variety of different analytes (F−, Pd0, H2O2, β-galactosidase, β-glucosidase, α-mannosidase and phosphatase). Most of these probes displayed excellent turn-on responses when treated with their respective analytes. Furthermore they could be used for detecting multiple analytes simultaneously (Chapter 4). By use of one Eu-based and another Tb-based probe, the simultaneous detection of two analytes was possible. This could further be extended to simultaneous three analyte detection by the additional employment of an organic coumarin-based probe. The last part of the thesis (Chapter 5) describes protocols for the rapid and efficient access to triazole-linked lanthanide-antenna complexes by use of the copper-catalyzed azide-alkyne cycloaddition reaction. For robust substrates, microwave heating at 100 °C enabled rapid (15-60 min) access to various lanthanide complexes, which could be isolated via simple precipitation. Using these conditions pure bi- and tri-homometallic lanthanide complexes could be prepared. A second protocol, for substrates carrying sensitive functionalities was also developed. The application of catalytic amounts of CuOAc, BimPy2 ligand, and a large excess of NaAsc afforded a variety of lanthanide complexes, among them caged responsive probes, in moderate to good yields.

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Nanowires are sensitive to external influences such as surface charges or external electric fields. An Atomic Force Microsope (AFM) is modified to perform back gating and tip gating measurements in order to understand the interaction between an external field, and surface charge and nanowire conductance. A 2D finite element method (FEM) model is developed to simulate the measured conductance. The model shows that surface states play a critical role in determining nanowire conductance. A 3D FEM model is developed to examine the influence of the AFM tip on the lateral resolution of the AFM tip in the electrostatic measurement. The radius of the AFM tip determines the lateral resolution of the tip. However, carrier concentration in the nanowire establishes a lower limit on the lateral resolution, for small tip radii. These results enable one to optimize Scanning Probe Microscopy experiments as well as inform sample preparation for nanowire characterization.

Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.

Thesis (M.S.)--University of Michigan, 1986.

Thesis (M.S.)--University of Michigan, 1986.

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

Theses (M.S.)--Marshall University, 2006. / Title from document title page. Includes abstract. Document formatted into pages: contains v, 75 pages including illustrations. Bibliography: p. 72-75.

Within this educational endeavor instrumental development was explored through the investigation of microwave induce stable electromagnetic waves within a non-linear yttrium iron garnet ferromagnetic waveguide. The resulting magnetostatic surface waves were investigated as a possible method of rapid analytical evaluation of material composition. Initial analytical results indicate that the interaction seen between wave and material electric and magnetic fields will allow phase coherence recovery andanalysis leading to enhancement of analytical value. The ferromagnetic waveguide selected for this research was a high quality monocrystalline YIG (yttrium iron garnet) film. Magnetostatic spin waves (MSW) were produced within the YIG thin waveguide. Spin waves with desired character were used to analytically scan materials within the liquid and solid phase.