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FRET peptidyl sensors for the detection of metal ionsWhite, Brianna Rose, 1981- 28 August 2008 (has links)
This research focuses on developing selective FRET peptidyl metal ion sensors as a portable and less costly alterative to traditional atomic spectrometric techniques. Initially, a selective sensor for Cu²⁺ was developed that consisted of glycine and aspartic acid residues and the FRET pair tryptophan (donor) and dansyl (acceptor). Aspartic acid's affinity for hard acid metals and Cu²⁺'s preference for square planar coordination was used as the basis of design. Although the sensor was designed to utilize the signal enhancement capabilities of FRET, quenching of both fluorophores occurred and proved to be the most sensitive means of quantifying Cu²⁺ binding. Nonetheless, the sensor provided a selective and sensitive response to Cu²⁺ at pH 7.0. Another FRET peptide metal ion sensor was designed with the help of a biological starting point, the mercury binding protein MerP. A sensitive FRET enhancement or "turn on" response was observed for Hg²⁺, as well as Zn²⁺, Cd²⁺ and Ag²⁺ in pH 7.0 solution. While a selective response for only Hg²⁺ was the ultimate goal of this study, this sensor is still an improvement over current systems which utilize a quenching mechanism for Hg²⁺ detection. While the previous studies investigated these sensors in aqueous solutions, the end goal was to devise a sensor based on an immobilized peptide chelator with FRET capabilities. To this end, immobilized, fluorophore labeled peptide studies were then conducted on Tentagel resin using a visible region FRET pair. A flow injection fluorescence analysis system using the immobilized fluorophore labeled peptide as the ion exchange material was also designed, allowing for the efficient analysis of fluorescence solutions. In addition to the work conducted with FRET sensors, studies were also conducted using magnetic [gamma]-Fe₂O₃ nanoparticles with PLCys immobilized onto the surface. The [gamma]-Fe₂O₃ nanoparticles are ideal supports since they can be magnetically collected and have a very large surface area to mass ratio. Finally, a method was developed to quantitatively screen metals bound to single Tentagel beads with immobilized peptides using ETV-ICP-MS. This method is an improvement over existing methods because it is nondestructive and simultaneously provides the absolute content of all metals bound.
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Metalation products of 1,6- and 1,4-heptadieneLauner, Curtis Ray January 1979 (has links)
No description available.
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Porphyrins for optical limiting applicationsAiken, Stuart January 2001 (has links)
A number of symmetric porphyrins containing both zinc(II) and lead(II) central metal ions have been prepared. Several routes to these compounds have been investigated and their merits evaluated. The conjugation of the chromophores has been extended by the inclusion of different <I>trans</I>- substituted arylethynyl substituents in the <I>meso</I>-position. An improved multigram method for the preparation of [bis-trimethylsilyethynylporphinato]zinc(II), which does not necessitate chromatographic purification, is described. The use of [5-triisopropylsilylethynylporphinato]zinc(II) for the preparation of donor/acceptor prophyrins via Sonogashira coupling, several of which were prepared, is also described. Investigations of the binding of 4(3<I>H</I>)pyrimidone with [5,5'-bis-[10,20-bis(3,5-di-<I>tert</I>-butylphenyl)-15-tri-iso-propylsilylethynyl-porphinyl]-1,3-butyn-1,4-diyl]dizinc(II) were made. The association constant was found to be 2500 ± 140 mol<sup>-1</sup> (ΔG = -4.6 Kcal/mol), significantly greater than that for 4(3<I>H</I>)pyrimidone alone (444 ± 5 mol<sup>-1</sup>), as determined by NMR dilution experiments. The crystal structures of [5,15-bis(3,5-bis-<I>tert</I>-butylphenyl)porphinato]zinc(II), [5,15-bis-(3,5-di-<I>tert</I>-butylphenyl)-10,20-bis-triisopropylsilylethynylporphinato]lead(II), [5,10,15,20-<I>tetrakis</I>-triisopropylsilylethynylporphinato]lead(II), 5,15-bis-(3,5-bis-<I>tert</I>-butylphenyl)-10,20-bis-phenylethynylporphyrin, [5,15-bis-(3,5-bis-<I>tert</I>-butylphenyl)-10,20-bis-(3-hydroxy-3-methyl-butynyl)porphinato]zinc(II),5,10,15,20-<I>tetrakis</I>-triisopropylsilylethynylporphyrin and [5,15-bis-(3,5-bis-<I>tert</I>-butylphenyl)-10-(4-N, N-dimethylaminophenylethynyl)-20-triisopropylsilylethynylporphinato]zinc(II) are also described.
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Mobilizationpurging of aqueous metal ions into supercritical carbon dioxideAger, Patrick. January 1998 (has links)
The technology of supercritical fluid extraction (SFE) offers the opportunity to efficiently extract both relatively non-polar analytes as well as ionic materials (such as metal ions) that can be mobilized with the addition of complexing reagents. The nebulizer of a conventional flame atomic absorption spectrometer (FAAS) was modified to extend the range of metals amenable to on-line detection. The flow injection thermospray-FAAS (FI-TE-FAAS) interface provided efficient detection for a variety of less volatile elements (Co, Cr(III), Cr(VI), Fe, Ni, Mn and Al) present as ions in aqueous media or as complexes in the supercritical fluid (SC-CO2) carrier phase. The range of possible metal analytes that can be monitored has been increased over the nine elements (Ag, As, Cd, Cu, Hg, Mn, Pb, Se and Zn) that could be detected with an all-silica interface. The acetylacetonate complexes offered considerable potential for metal detection in an SC-CO2 carrier phase. Limits of detection (LODs) were used to compare the instrument responses to different metals. (Abstract shortened by UMI.)
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Complexation of polyether carboxylic acids and estersʾOṅʻ Mraṅʻʹ, Ūʺ. January 1974 (has links)
No description available.
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Metal ion effects on the T box antiterminator RNA and complex formation with tRNA /Jack, Karen D. January 2007 (has links)
Thesis (Ph.D.)--Ohio University, March, 2007. / Includes bibliographical references (leaves 165-175)
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Metal ion complexing properties of the highly preorganized ligand 1, 10-phenanthroline-2,9-dicarboxylic acid /Dean, Nolan Edward January 2007 (has links) (PDF)
Thesis (M.S.)--University of North Carolina Wilmington, 2007. / Includes bibliographical references (Leaves: 135-136)
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A study of cryptate complexes and pendant arm ligand complexes /Clarke, Philip. January 1992 (has links) (PDF)
Thesis (Ph. D.)--Dept. of Physical and Inorganic Chemistry, University of Adelaide, 1993. / Typescript (Photocopy). Includes bibliographical references.
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Sequestration of metal and metalloid ions by thermophilic bacteriaHetzer, Adrian. January 2007 (has links)
Thesis (Ph.D. Biological Sciences)--University of Waikato, 2007. / Title from PDF cover (viewed March 6, 2008) Includes bibliographical references (p. 111-134)
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A structural thermodynamic and equilibrium study of chiral pendant arm triaza macrocyclic ligand complexes: towards the formation of metal-ion activated molecular receptors : a thesis submitted for the degree of Doctor of Philosophy at the University of Adelaide (Faculty of Science) /Weeks, Jennifer Megan. January 2000 (has links) (PDF)
Thesis (Ph.D.)--University of Adelaide, Dept. of Chemistry, 2000? / Errata page pasted opposite title page. Includes bibliographical references.
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