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Modification And Characterization Of Poly[Styrene-Co-Maleic Anhydride] With Fluorescent Probes, Ronald Difelice

Theses

In this study, various poly[styrene-co-(maleic anhydride)] copolymers (50/50, 75/25, 86/14, and 92/8) were modified with the 4-nitroaniline and 4-phenylazoaniline dyes. A synthesis, collection, and purification procedure was developed, and the resulting modified polymers were characterized primarily using elemental analysis, Fourier Transform Infrared analysis (FT-IR), Thermogravimetric Analysis (TGA), and Differential Scanning Calorimetry (DSC). Elemental analysis allowed percent incorporation results to be determined for each copolymer-dye synthesis. Percent incorporation was approximately 70% for the 50/50 copolymers, and 55% for the 75/25 copolymers, with no significant difference between the 4-nitroaniline and the 4-phenylazoaniline modified copolymers. For the 86/14 and 92/8 modified copolymers, however, …

Preparation Of Enzyme - Analyte Conjugates Containing Linker Arms, Tong Zhu

Theses

In this study, we are examining the effect of the length and polarity of peptide linker arms on the performance of enzyme - analyte conjugates in a reagentlimited heterogeneous immunoassay which utilizes a solid phase format. In our model system, our goal is to attach benzoylecgonine, the primary urinary metabolite of cocaine, to glucose oxidase by a series of peptide linker arms. Peptide linker arms were synthesized using the fluorenylmethoxycarbonyl (Fmoc) solid phase peptide synthesis strategy described by Stewart and Young (1). We attached the BEC to the exposed amino - terminal end of the peptide linker arm by the …

Mechanism Of Inhibitation Of Human Leukocyte Elastase By Benzisothiazolinone-1,1-Dioxides, Catherine Franke

Theses

Benzisothiazolinone- 1,1 -dioxides are potent, time-dependent, reversible inhibitors of human leukocyte elastase (HLE) that demonstrate the ability to inhibit HLE catalyzed degradation of insoluble elastin. A stoichiometry of 1.4 to 1.47 equivalents per mole of enzyme indicates that these compounds are efficient inhibitors of HLE. The proposed mechanism of HLE inhibition has been investigated and the data are consistent with acylation of the active site serine followed by elimination of the leaving group to form a reactive sulfonyl imine intermediate. The reactive intermediate can undergo hydration followed by deacylation or it can react with an enzyme nucleophile to form a …

Development Of A Femtosecond Time-Resolved Raman Spectrometer For Hemoglobin Studies., Junbo Chen

LSU Historical Dissertations and Theses

A femtosecond time-resolved Raman spectrometer is developed to study the ultrafast dynamics of hemoprotein. The laser system consists of a dye laser synchronously pumped by the SHG of compressed ML Nd:YAG laser pulse, and a Ti:sapphire regenerative amplifier using chirped-pulse-amplification technique. The laser system provides 350 fs pulses output with 0.4 mJ/pulse energy at the repetition rate of 1 kHz. The tunability covers the whole Ti:sapphire lasing range with the use of different laser dye. Femtosecond time-resolved resonance Raman experiment shows that the ligand photodissociation quantum yield depends on the nature of ligand. With three ligands studied, CO has about …

Structure Elucidation And Chemistry Of Plant Natural Products In Search Of Bioactive Compounds., Heekyung Tak

LSU Historical Dissertations and Theses

A phytochemical study of regional members of five genera of the family Asteraceae was performed in search of bioactive natural products. The aerial parts of Garberia heterophylla, an endemic of the Florida central ridge scrub, were investigated and afforded the known guaianolide-type sesquiterpene lactone eupahakonesin, 2,6-dimethoxybenzoquinone, epifriedelinol and the novel diterpene, garberic acid. Aerial parts of Polymnia uvedalia provided three kaurane-type diterpenes, ($-$) kaur-16-en-19-oic acid, 3$\beta$-angeloyloxy-kaur-16-enic acid, 18-angeloyloxy-kaur-16-enic acid and two melampolides, enhydrin and 2$\sp\prime$, 3$\sp\prime$-dehydromelnerin A. The molecular structure of enhydrin was determined by single crystal X-ray diffraction. Verbesina virginica roots contained three eudesmane p-coumarate, 6$\beta$-p-coumaroyloxy-eudesm-4(15)-ene, 6$\beta$-p-coumaroyloxy-eudesm-4(3)-ene, 6$\beta$-p-coumaroyloxy-4$\beta$-hydroxyeudesmane and …

Studies Of V-Nitrogenase From Azotobacter Vinelandii: Structural Variations, Temperature And Solvent Effects., Carol Zembiak Blanchard

LSU Historical Dissertations and Theses

When Q-Sepharose was used in the purification of the V-nitrogenase proteins from Azotobacter vinelandii, an increase in resolution was observed which resulted in a separation of the nitrogenase component 1 protein (Av1$\sp\prime$) into two forms, labeled Av1$\sp\prime\sb{\rm A}$ and Av1$\sp\prime\sb{\rm B}.$ Even though both forms possessed the same enzymatic behavior, Av1$\sp\prime\sb{\rm A}$ exhibited a lower specific activity and migrated during gel filtration with an apparent lower molecular weight than Av1$\sp\prime\sb{\rm B}.$ Furthermore, SDS-polyacrylamide gel electrophoresis showed different relative compositions of the two major subunits of both forms with Av1$\sp\prime\sb{\rm A}$ possessing a trimer $(\alpha\beta\sb2)$ pattern compared to the tetramer $(\alpha\sb\beta\sb2)$ …

Synthesis, Characterization, Liquid Crystals And Crosslinking Of Poly(Gamma-Alkyl-Alpha,L-Glutamates)., Javier Nakamatsu

LSU Historical Dissertations and Theses

As most polypeptides, poly($\gamma$-alkyl-$\alpha$,L-glutamates) exhibit the ability to exist in well defined chain conformations of extensive order such as the $\alpha$-helix. This helical conformation imparts a rod-like character to the polymer which is maintained in the melt and in certain solvents at particular concentrations. This dissertation reports the synthesis and characterization of poly($\gamma$-alkyl-$\alpha$,L-glutamates), in particular, of poly($\gamma$-stearyl-$\alpha$,L-glutamate) (PSLG), poly($\gamma$-benzyl-$\alpha$,L-glutamate) (PBLG), and poly($\gamma$-stearyl-$\alpha$,L-glutamate)-co-poly$(\gamma$-benzyl-$\alpha$,L-glutamate). Polymerization studies of PSLG with primary, tertiary, and silylated amines as initiators; and PBLG with coinitiators are described. The labeling of PSLG with a fluorescein dye is also explained. All the polymers were obtained from the corresponding N-carboxyanhydride …

Solution Behavior Of Cascade Polymers., Keunok Han Yu

LSU Historical Dissertations and Theses

This thesis consists of four chapters. In the first, a general introduction is presented. Chapter 2 deals with the characterization of polyamidoamine (PAMAM) cascade polymers. Diffusion coefficients of four different generations (generation 3, 5, 7, and 9) of PAMAMs were measured in aqueous solutions by dynamic light scattering. Generation 3 and 5 were characterized again, after labeling with fluorescein isothiocyanate, by fluorescence photobleaching recovery. The dynamic light scattering results depended on the concentration of added salt in the low salt limit, while the fluorescence values were almost independent of salt concentration. The polyelectrolyte effects, or solution nonidealities, strongly affected light …

A Study Of The Synthesis Of 2,2',4,4'-(4,4'-Bioxazoles)-5,5'(4h,4'H)-Diones, Their Isomers, And The Products Of Nucleophilic Ring Openings, Daniel Francis Gloster

Doctoral Dissertations

The purpose of this research was to investigate routes towards the synthesis of $\alpha,\alpha\sp\prime$-dehydrodimeric amino acids. This dissertation describes various methods of effecting dehydrodimerization of bioxazoles. Bioxazoles are good candidates to serve as precursors to $\alpha\,\alpha\sp\prime$-dehydrodimeric amino acids, because they are $\alpha,\alpha\sp\prime$-dehydrodimeric amino acid derivatives. This dissertation describes the synthesis and characterization of d,l and meso 4,4$\sp\prime$-bioxazoles as well as, 2,4$\sp\prime$-bioxazoles.

A variety of bioxazoles were synthesized and some were subjected to nucleophilic ring opening. It had been reported that nucleophilic attack at the bioxazole ring caused the dehydrodimeric carbon-carbon bond to be cleaved. Results of this work indicate that …

Reactions Of A Dimolybdenum Cage Complex With Phosphorus And Nitrogen Nucleophiles And The Synthesis And Reactions Of Heterobimetallic Cages, Haiying Yang

Doctoral Dissertations

The reactions of the dimolybdenum cage complex Mo(CO)$\sb4$-$\rm \lbrack\sp{i}Pr\sb2NPO\rbrack\sb4Mo(CO)\sb4\sp{*}$ with phosphorus and nitrogen nucleophiles were studied. This dimolybdenum cage complex reacted with tertiary phosphines of the type PPh$\sb2$R (R = Ph, Me, H) in refluxing toluene. In each case, incorporation of a single phosphine led to the loss of three carbonyls to form orange complexes of the type $\rm Mo(CO)\sb3\lbrack \sp{i}Pr\sb2NPO\rbrack \sb4Mo(CO)\sb2PPh\sb2R$(2, 3, 4). The X-ray molecular structure of 2 has been determined. This revealed that a cage P-O-P bond has been cleaved near the substitution site with the resulting phosphinito oxygen replacing a second CO. Additionally, the phosphido group …

Evaluation Of Polymer Coated Attenuated Total Reflection (Atr) Elements For The Analysis Of Organic Compounds In Aqueous Solution, Marc C. Ertan-Lamontagne

Doctoral Dissertations

A significant limitation of ATR/FTIR for the analysis of aqueous solutions is the relatively high bulk concentration of analyte required. One approach to improving the detection of an analyte is to incorporate a thin polymeric phase at the surface of the ATR element. The purpose of the polymeric phase is to extract the analyte of interest and concentrate it within the depth of penetration of the evanescent wave. Utilizing a very high molecular weight poly(vinyl chloride) phase the time necessary to reach equilibrium for a 0.05% (v/v) nitrobenzene in a 1.5% (w/v) methanol/water solution was over 60 minutes. A study …

Part I Synthesis And Study Of Cyclic Sulfamates Part Ii Investigation Of Endocyclic Nucleophilic Substitution At Tetracoordinate Sulfur(Vi), Martin George Kociolek

Doctoral Dissertations

Part I. 5-Nitro-N-(p-toluenesulfonyl)-1,2,3-benzoxathiazole-2,2-dioxide was synthesized and reacted with various nucleophiles. Nitrogen nucleophiles attacked the exocyclic sulfur atom resulting in cleavage of the tosyl group. This is due in part to the acidity of the parent benzoxathiazole ring. A series of substituted N-H-1,2,3-benzoxathiazole-2,2-dioxides were synthesized and their pK$\sb{\rm a}$ values were determined. An ab initio study was also undertaken on a simple sulfamate model in order to determine the origin of the increased acidity of the cyclic sulfamates, compared to their acyclic analogues. It was determined that the increased acidity was directly affected by the conformation of the neighboring heteroatoms. This …

Chiral Separations Using Bile Salts In Capillary Electrophoresis, James George Clothier

Doctoral Dissertations

Micellar electrokinetic capillary chromatography (MECC) using surfactant solutions containing bile salts, polyoxyethylene ethers and methanol was used to produce chiral separations. A capillary electrophoresis instrument was assembled in the laboratory. Initial testing and optimization of the instrument involved the separation of organic acids using capillaries zone electrophoresis techniques. Polymer coated capillaries were prepared and tested in the instrument. Bile salt solutions were characterized by viscosity and nuclear magnetic resonance. The effects of various solution conditions, such as pH, ionic strength and concentration of bile salt solutions on chiral resolution were investigated by MECC. Enhancement in chiral resolution was obtained using …

Part I Synthesis, Functionalization And Metal Complexation Of Polyamine Macrocycles Part Ii Synthesis And Dynamic Nmr Studies Of Bicyclic Ureas, Daniel Cope Hill

Doctoral Dissertations

Part I. The syntheses and characterizations of novel bicyclic tetraamines (shown below) have been accomplished. The complexation of bicyclic tetraamines (R = CH$\sb3)$ with Li$\sp+$ and Na$\sp+$ have been studied by NMR spectroscopy. These tetraamines are strong bases and selective Li$\sp+$ binders. The parent "cross-bridged cyclam" (R = H; X = Y = CH$\sb2)$ was functionalized with a variety of ligating groups containing heteroatoms. Several of the ligands were investigated as possible radiopharmaceutical ($\rm\sp{99m}Tc$) imaging agent precursors.

Syntheses of non-adjacent selectively functionalized tetraazacycloalkanes have also been developed.

Part II. Synthesis and dynamic NMR studies of intramolecular transamidation of bicyclic urea …

I Synthesis And Dynamic Studies Of Bifunctional Compounds Having Potential Intramolecular Interactions Ii Controlled Release Antifouling Coatings: Approaches To Controlled Release Of Gamma-Decanolactone And 2-Hexanoylfuran Into Seawater, Craig Anthony West

Doctoral Dissertations

I. Potentially reactive, bifunctional compounds 1 and 127 have been studied, and both compounds have been found to undergo rapid base-catalyzed degenerate topomerization. The topomerization processes, which in the case of 1 represents a degenerate transamidation and in the case of 127 a degenerate transesterification, have been studied in acetonitrile-d$\sb3$ and D$\sb2$O under a variety of conditions by the DNMR method. In both cases, the presence of a stable tetrahedral anion intermediate can be inferred from analysis of NMR and IR spectra. In the case of 1, the unusually high rate of topomerization can be attributed to the presence of …

An Assessment Of The Potential To Use Water Chemistry Parameters To Define Ground Water Flow Pathways At Grand Canyon National Park, Arizona, Kim Alison Zukosky

UNLV Retrospective Theses & Dissertations

The purpose of this study is to assess the potential to use water chemistry parameters to determine ground water flow pathways at the south rim of Grand Canyon National Park, Arizona. South rim spring, ground, and surface waters and one north rim spring were sampled from September 1992 through September 1993. Field measurements (pH, electrical conductivity, alkalinity, temperature, total dissolved solids, and dissolved oxygen), major anion (fluoride, chloride, bromide, nitrate, phosphate, and sulfate) concentrations, selected trace element concentrations, and the ratios of the stable isotopes of oxygen and hydrogen. Major anion, trace element, and field measurement data were analyzed using …

X-Ray Absorption And Electron Paramagnetic Resonance Studies Of Azotobacter Vinelandii Nitrogenase., Roland Carroll Tittsworth

LSU Historical Dissertations and Theses

Fe K-edge Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy was used to investigate the metal-cluster structure of both the Mo-containing (Av1) and V-containing (Av1$\sp\prime$) nitrogenase component 1 proteins of Azotobacter vinelandii in their as-isolated and thionine-oxidized states. Using the EXAFS data, plausible distance assignments were made for the cofactor clusters. It was shown that small but consistent distance changes occur in both Av1 and Av1$\sp\prime$ upon thionine oxidation. Furthermore, the EXAFS of Av1$\sp\prime$ is very similar to that of Av1, supporting the proposal that the two proteins have homologous metal cluster structures. Fe K-edge and Mo K-edge EXAFS were used …

Host-Guest Chemistry Of Cofacial Binuclear Copper(Ii) And Zinc(Ii) Complexes Of Bis(Beta-Diketone) Ligands., Laurie A. Brown

LSU Historical Dissertations and Theses

We have been synthesizing cofacial binuclear copper(II) and zinc(II) complexes using bis($\beta$-diketone) ligands in order to design a host complex which selectively binds guest molecules and demonstrates catalytic activity. The metal atoms are held by the chelating acetylacetonate groups, of the bis($\beta$-diketone) ligands, in adjacent parallel planes separated by a cavity into which the guest molecule fits. The host-guest interactions are described. The synthesis of these complexes are discussed beginning with the synthesis of the substituted naphthalenes which bridge the meta-acetylacetonate planes. We needed 2,7-dimethylnaphthalene-1-carbonitrile for the synthesis of the bis($\beta$-diketone) ligand, NBAH$\sb2$-1-CN. After the first recrystallization of 2,7-dimethylnaphthalene-1-carbonitrile, it …

Homo- And Hetero-Nuclear Clusters Of Platinum And Rhenium, Leijun Hao

Digitized Theses

ABSTRACT HAS BEEN ARCHIVED 07/22/97;

Intramolecular Aldol Condensation Reactions And Transacetalization Equilibria, Junan Guo

Digitized Theses

Part I. Intramolecular aldol condensation reactions. The detailed kinetics and equilibrium for the intramolecular aldol condensation reaction of 2,5-hexanedione, 2, 6-heptanedione, 1-phenyl-1, 5-hexanedione and 5-oxohexanal were studied and correlated in terms of Marcus theory. All the reactions, with the readily explained exception of the intramolecular aldol addition of 5-oxohexanal, gave us approximately constant intrinsic barriers: 14.49 {dollar}\pm{dollar} 0.82 kcal/mol for the intramolecular aldol addition step and 13.99 {dollar}\pm{dollar} 0.74 kcal/mol for the subsequent dehydration step, which are also in excellent agreement with the intrinsic barriers found for intermolecular aldol condensation reactions.{dollar}\sp{lcub}16{rcub}{dollar} This means that Marcus theory is applicable to intramolecular …

Spectroscopic Properties Of Copper Binding To The Protein Metallothionein, Anna Rae Green

Digitized Theses

Metallothionein (MT) is a low molecular weight protein found in the kidneys and livers of all mammals. Twenty of its 61 or 62 amino acid residues are cysteinyl residues, allowing the protein to act as an impressive chelating agent. Although it has been well established that mammalian MT binds seven M(II) (M = Cd(II), Zn(II), Hg(II)) ions tetrahedrally in two metal-thiolate clusters of the form M{dollar}\sb4{dollar}(S{dollar}\rm\sb{lcub}cys{rcub})\sb{lcub}11{rcub},{dollar} (the {dollar}\alpha{dollar} domain) and {dollar}\rm M\sb3(S\sb{lcub}cys{rcub})\sb9,{dollar} (the {dollar}\beta{dollar} domain), little is known about the structure of copper-containing metallothioneins. In this thesis, absorption, circular dichroism (CD) and emission spectroscopies and excited state lifetime data are …

Induction Of Aryl Hydrocarbon Hydroxylase And Ethoxyresorufin O-Deethylase In Human And Murine Cells By 2,3,7,8-Tetrachlorodibenzo-P-Dioxin (Tcdd) And Polycholrinated Biphenyls (Pcbs)., Andreas. Vamvakas

Electronic Theses and Dissertations

To assess the relevance of H4IIE for human populations, we examined levels of aryl hydrocarbon hydroxylase (AHH) and ethoxyresorufin O-deethylase (EROD) activities H4IIE rat liver, HepG2 human liver and MCF-7 human breast cells after exposure to a variety of HAHs. These included TCDD, and three coplanar non-ortho substituted polychlorinated biphenyl (PCB) congeners: 3,3$\sp\prime$,4,4$\sp\prime$-tetrachlorobiphenyl (PCB 77), 3,3$\sp\prime$,4,4$\sp\prime$5-pentachlorobiphenyl (PCB 126), and 3,3$\sp\prime$,4,4$\sp\prime$,5,5$\sp\prime$-hexachlorobiphenyl (PCB 169), either alone or in combination. AHH and EROD activities were also examined after treatment with muscle tissue extracts of Lake Ontario rainbow trout (Oncorhynchus mykiss). H4IIE was generally more sensitive to all HAH treatments. AHH and EROD activities …

The Structure And Spectroscopic Properties Of Langmuir-Blodgett Films Of Perylene Tetracarboxylic Derivatives., Eric G. Johnson

Electronic Theses and Dissertations

A series of perylene tetracarboxylic diimides and monoimides have been fabricated into Langmuir and Langmuir-Blodgett films. These films have been spectroscopically characterized through UV-visible absorption, steady-state fluorescence, infrared and Raman techniques. Molecular exciton and excimer formation have been observed for these films. The average molecular orientation of the chromophore was deduced through infrared transmission and reflection/absorption techniques. Electronic spectroscopy revealed the nature of the packing of the materials. The role of subphase/molecule and molecule/molecule interactions in the structure of the film were discussed, as well as the role of the imide substitution. These materials were successfully incorporated, as donors, into …

Two-Dimensional Nuclear Magnetic Resonance Studies Of Thymosin-Alpha(1) (A Myosin Light Chain Kinase Activating Peptide), And Ribonuclease A In The Presence Of Uridine Vanadate., Timothy Daniel. Veenstra

Electronic Theses and Dissertations

1. The structure of the peptide thymosin $\alpha\sb1$ has been investigated by circular dichroism and one- and two-dimensional nuclear magnetic resonance spectroscopy. Thymosin $\alpha\sb1$ is a highly acidic peptide composed of 28 amino acid residues. Through the use of circular dichroism and two-dimensional nuclear magnetic resonance techniques, the structure of thymosin $\alpha\sb1$ in 30% (v/v) deuterated 2,2,2-trifluoroethanol has been solved. Thymosin $\alpha\sb1$ contains an $\alpha$-helix extending from residue 16 to 26 and a turn between residues 5 and 8. Thymosin $\alpha\sb1$ has been shown to be a potent activator of skeletal muscle myosin light chain kinase, a well known calmodulin-dependent …

Marcus Theory Applied To Acetal Cleavage And Aldol Reactions, Jonathan Arthur Barker

Digitized Theses

The acid catalyzed and uncatalyzed hydrolysis of the acetal 2,2-dimethoxypropane (DMOP) and the ortho ester trimethylorthoacetate (TMOA) have been studied in aqueous solution at 25{dollar}\sp\circ{dollar}C. Theoretical and experimental evidence have been found for a base catalyzed E2 mechanism of DMOP hydrolysis proceeding through an enol ether. This mechanism is neither predicted nor observed for TMOA hydrolysis. The specific acid catalyzed and uncatalyzed rate constants for hydrolysis are for DMOP k{dollar}\rm\sb{lcub}H+{rcub}=(2.5\pm0.3)\times10\sp3\ M\sp{lcub}-1{rcub}s\sp{lcub}-1{rcub},\ k\sb w=(3.6\pm0.2)\times10\sp{lcub}-8{rcub}\ s\sp{lcub}-1{rcub},\ k\sb{lcub}OH-,E2{rcub}=(2.8\pm0.4)\times10\sp{lcub}-8{rcub}\ M\sp{lcub}-1{rcub}s\sp{lcub}-1{rcub},\ and\ for\ TMOA\ k\sb{lcub}H+{rcub}=(2.05\pm0.12)\times10\sp4\ M\sp{lcub}-1{rcub}s\sp{lcub}-1{rcub},\ k\sb w=(3.7\pm0.3)\times10\sp{lcub}-6{rcub}\ s\sp{lcub}-1{rcub}.{dollar} General acid catalysis was observed for TMOA with four general acids. From the Bronsted plot, {dollar}\alpha=0.76\pm0.05.{dollar} …

Electronic Structure Of Gold-Silver Bimetallics, Arthur Bzowski

Digitized Theses

The main thrust of this thesis concerns studies of the electronic structure of Au-Ag bimetallic materials, both in bulk alloys and in metallic overlayers on Ru(001). First, a series of bulk Au-Ag alloys: Au{dollar}\rm\sb{lcub}0.75{rcub}Ag\sb{lcub}0.25{rcub},\ Au\sb{lcub}0.67{rcub}Ag\sb{lcub}0.33{rcub},\ Au\sb{lcub}0.50{rcub}Ag\sb{lcub}0.50{rcub},\ Au\sb{lcub}0.25{rcub}Ag\sb{lcub}0.95{rcub},\ and\ Au\sb{lcub}0.05{rcub}Ag\sb{lcub}0.95{rcub}{dollar} has been studied using X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), and X-ray absorption near-edge structure (XANES). It is found that in alloys with {dollar}>{dollar}50% atomic Au, the alloy d-band width narrows little relative to that of pure Au; however at 50% (and less) atomic Au concentration, the widths of the Au-Ag alloy d-band are much smaller than that …

Purification, Characterization, And Functional Investigations Of Novel Platelet Proteins., Jeffrey Stephen. Baldwin

Electronic Theses and Dissertations

Recently, a novel Kunitz inhibitor of trypsin-like enzymes has been discovered in bovine platelets that has a higher degree of association for plasmin than trypsin, and thereby has been termed bovine platelet plasmin inhibitor (BPPI). Basic problems in the purification, resulting in protein that was essentially insoluble, has hampered structural determinations by x-ray or NMR analysis. An investigation into the cause of the protein insolubility has revealed that an excessively high concentration of acetonitrile, used to elute the protein from a C18 reversed-phase cartridge, was most probably the cause of the insolubility. Concentrated BPPI solutions permitted the preparation of a …

Metalated Macrocyclic Receptors., James Edward. Kickham

Electronic Theses and Dissertations

The dissertation describes the incorporation of a stable organopalladium fragment into several macrocyclic structures, in which three of four palladium coordination sites are permanently occupied by an S$\sb2$C ligand "bracket". The remaining metal site is filled by a more labile donor, and is used for binding ancillary ligands (substrates) such as phosphines, o-aminopyridine, DNA nucleobases and hydrazine derivatives. Chapter 2 describes the synthesis, oxidative addition, and coordination chemistry of (Pt(TT(11) MC)) (BF$\sb4\rbrack$ (4), (PD(TT(11) MC)) (BF$\sb4\rbrack$, (8) and (Pd(pr-TOMB-1)) (BF$\sb4\rbrack$ (14), in which one donor (E = S,O) is displaced by stronger ancillary ligands, as confirmed by X-ray structural data …

Some Aspects Of Glutathione And L-Arginine/Nitric Oxide Metabolism In The Maintenance Of Platelet Function., Daniel Joseph. Sexton

Electronic Theses and Dissertations

Evidence is presented here for the regulation of platelet activation by intra-platelet levels of glutathione (GSH) and L-arginine. Our data is consistent with the intra-platelet GSH ((GSH) $\sb{\rm ip}$) modulation through the regulation of the thromboxane A$\sb2$ (TxA$\sb2$) biosynthesis. The reduction of (GSH) $\sb{\rm ip}$ by 100 $\mu$M 1-chloro-2,4-dinitrobenzene (CDNB) enhanced thrombin-induced platelet aggregation and ADP-induced platelet aggregation was inhibited by the elevation of (GSH) $\sb{\rm ip}$ through a facilitative GSH-specific transport system. Platelet facilitative GSH uptake was subsequently characterized as being Na$\sp+$-independent, concentration dependent (K$\sb{\rm M}$ and V$\sb{\rm max}$ for GSH uptake in platelet plasma membrane vesicles (PPMV) is …

Synthesis And Characterization Of Water Soluble Chitosan Derivatives., Javier Macossay

LSU Historical Dissertations and Theses

Chitin, one of the most ubiquitous natural polymers, remains underutilized. The integral part chitin plays in natural biocomposites suggests that synthetic composites incorporating chitin should exhibit interesting properties, both with respect to strength and biodegradability. Due to a very strong hydrogen bonding, chitin is a very intractable material, but its derivative, chitosan, is very amenable to chemical modifications. Controlled deacetylation of chitin produces water soluble chitosan that is very efficient in complexing metals and natural biomolecules; major applications in water purification are reviewed. In an effort to produce more water soluble derivatives of chitosan, with potential applications in the cosmetics …