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Analyte Rebinding Of Optimized Molecularly Imprinted Polymers In Water, Sayantan Roy

Master's Theses and Capstones

A series of non-covalent Molecularly Imprinted Polymers (MIPs) were prepared using caffeine and guanosine separately as template molecules. A wide variety of MIPs were prepared by varying a number of formulation parameters, including the template, recognition monomer, crosslinking agent and porogen types and concentrations. The specificity and selectivity of the MIPs were determined by rebinding studies in an aqueous medium using HPLC detection and the results were supported by gas adsorption experiments. Rebinding conditions, such as the pH and MIP concentration were also varied to determine the best conditions for analyte recognition. By using variety of polymerization conditions the particle …

Structural Analysis Of Cytokine Signaling Modulators, Cristina Ileana Silvescu

Doctoral Dissertations

The N-linked glycans attached to cytokine receptors modulate signal transduction by interacting with galectin-3 and generating a cell surface lattice. This opposes constitutive endocytosis and reduces the thresholds for cytokine signaling. The preferred ligands for galectin-3 are the poly-N-acetyl lactosaminylated tetra-antennary glycans which are synthesized by Mgat 5 and are present at high levels in tumor cells. A null mutation in Mgat 5 inhibits lattice formation and cancer progression in cells with an oncogenic background. GlcNAc feeding reestablishes lattice formation, cytokine signaling and tumorigenesis.

A MALDI-TOF analysis was employed to identify the N-glycans involved in modulating signal transduction in wild …

Investigation Of Copper(Ii) Complexes: I Copper(Ii) Complexes Of Tryptophan And Its Analogues As Postcolumn Interaction Components For Indirect Fluorescence Detection Of Amino-Containing Analytes Ii High-Performance Liquid Chromatographic Separation Of Copper(Ii) Azamacrocyclic Complexes, Xiaoxuan Shen

Doctoral Dissertations

The initial phase of this project investigates the use of copper(II) complexes of tryptophan and its analogues for indirect fluorescence detection in high-performance liquid chromatography. First, indirect photometric and fluorometric detection in high performance liquid chromatography (HPLC) is reviewed, giving the functional definition of indirect detection employed for this project, distinguishing different approaches to indirect photometric and fluorometric detection in HPLC, and explaining the basis of indirect fluorescence detection using copper(II) complexes of tryptophan and its analogues as postcolumn interaction components. Subsequent studies were conducted to develop and apply indirect HPLC detection for detecting specific mono-amino sugars, glucosamine, galactosamine, and …

Regulation Of Rod Photoreceptor Phosphodiesterase (Pde6) By The Glutamic Acid -Rich Protein 2 (Garp2), Dana C. Pentia

Doctoral Dissertations

Rod photoreceptor phosphodiesterase (PDE6), the central enzyme of visual transduction in vertebrate photoreceptors, associates with the disk membranes of the rod outer segment (ROS) of the photoreceptor cell. This association insures the high efficiency of activation by the G-protein, transducin, and the precise control of its inactivation. In addition to binding to transducin during visual excitation, PDE6 is hypothesized to be regulated by other interacting proteins.

The first aim of this research was to isolate and identify the proteins that interact with PDE6 during various stages of the visual signaling pathway. We evaluated methods for solubilizing PDE6 and its binding …

I Peptide Isosteric Replacement Preparation Using Zinc-Mediated Chain Extension-Aldol Reactions Ii Formal Synthesis Of (+)-Brefeldin A Iii Zinc-Mediated Chain Extension Reactions With Substituted Carbenoids, Weimin Lin

Doctoral Dissertations

A series of amino acid derived alpha-substituted-gamma-keto amides and esters have been prepared by zinc-mediated chain extension and tandem chain extension aldol reactions with various aldehydes and ketones. An efficient diastereoselective synthetic route has been developed to approach a proposed inhibitor for HCMV (Human Cytomegalovirus) protease using this zinc-mediated tandem chain extension-aldol reaction as the key step. An asymmetric formal synthesis of (+)-Brefeldin A has been developed in which the zinc-mediated ring expansion/oxidation/elimination method constitutes a key step. Preparation of beta-alkyl-gamma-keto esters through a chain extension reaction using substituted carbenoids has also been accomplished.*.

Analysis Of The Role Of Poly(A) -Binding Protein (Pab1) In The Mrna Degradation Process In Yeast, Gang Yao

Doctoral Dissertations

The mRNA deadenylation process influences multiple aspects of protein synthesis and is known to be the major factor controlling mRNA decay rates. My data demonstrates that yeast PAB1 plays both positive and negative roles in controlling deadenylation, and I have identified particular regions of PAB1 involved in controlling different aspects of the mRNA degradative process. I have found that yeast PAB1 does not play a simple, obstructionist role in regulating CCR4 deadenylation. Instead, PAB1-PAB1 protein interactions, as mediated by the PAB1 proline-rich region (P domain) and the RRM1 domain, are required for the CCR4 deadenylase activity. The P and RRM1 …

Theoretical And Experimental Studies Of Reactive Organic Molecules, Kaleen Marie Konrad

Master's Theses and Capstones

Chapter I. Density functional theory calculations were used to examine the interconversions of C5H6 and C 6H8 isomers. On the C5H6 surface, cyclobutenylcarbene is predicted to rearrange to 1,2-cyclopentadiene. Interconversion of cyclobutylidenecarbene and cyclopentyne has a small barrier. For the C6H8 surface, cyclopentenylcarbene is predicted to rearrange to bicyclo[3.1.0]hex-5-ene and further to 1,3-cyclohexadiene. Cyclopentylidenecarbene can easily interconvert with cyclohexyne. These results are in accord with experimental results, to date.

Carbene precursors via a cyclopropanated phenanthrene, 1,1-dihalo-1a,9b-dihydro-1H-cyclopropa[I]phenanthrene, were studied.

Chapter II. Isodesmic and homodesmic equations at B3LYP/6-311+G(d,p) level of theory have been used to estimate strain for the series of cyclic …

Group 12 And Group 13 Metal Complexes Of Cross-Bridged Tetraamine Macrocycles, Wei-Chih Lee

Master's Theses and Capstones

The use of radiometal-based radiopharmaceuticals for the therapy and diagnostic imaging of various diseases is rapidly increasing. Metal complex stability in vivo is an important factor to keep the metal chelate intact under physiological conditions for the radiopharmaceutical application. A novel class of cross-bridged tetraazamacrocycles with nonadjacent nitrogens bridged by an ethylene unit was developed to make metal complexes with good thermodynamic stability and higher kinetic inertness towards dissociation. Complexes of Ga(III) and In(III) radionuclides are widely used in diagnostic imaging and their respective half-lives are convenient for specific diseases. The new complexes [In-CB-DO2A]+ and [In-CB-TE2A]+ have been prepared by …

Synthetic Approaches To Cis,Cis-1,3,5-Triaminocyclohexane (Tach) And Tach-Based Ligands, Allison Lisa Lindell

Master's Theses and Capstones

Cis, cis-1,3,5-triaminocyclohexane (tach) has been synthesized according to various routes, and the methods were evaluated on the basis of product yield, number of steps, and expense of reagents. The conversion of cis, cis-1,3,5-cyclohexanetricarboxylic acid to the desired product by the Curtius rearrangement, as previously described in the literature, was found to be the most suitable procedure based on yield and number of steps. From the standpoint of cost, the reagents of the Curtius rearrangement were derived from inexpensive, commercially available starting materials. The yields of the synthesis are variable, and preliminary studies of yield optimization are described.

Three ligands based …