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Research In Natural Product Chemistry, Nathan Krause 2010 Olivet Nazarene University

Research In Natural Product Chemistry, Nathan Krause

Student Scholarship - Chemistry

Natural product chemistry is a branch of chemistry that deals with the isolation, identification, and study of the chemical characteristics of chemical substances produced by living organisms. The southwestern United States has a variety of indigenous plants many of which have not been investigated for their chemical compounds but have Native American herbal uses. The aim of this summer internship was to do extractions on plants and test them for medical potential.


On Probing Human Fingertips In Vivo Using Near-Infrared Light: Model Calculations, Jerry Goodisman, Joseph Chaiken 2010 Syracuse University

On Probing Human Fingertips In Vivo Using Near-Infrared Light: Model Calculations, Jerry Goodisman, Joseph Chaiken

Chemistry - Faculty Scholarship

We probe volar-side fingertip capillary beds with nearinfrared laser light and collect Raman, Rayleigh, and Mie scattered light and fluorescence. The results are interpreted using radiation transfer theory in the single-scattering approximation. The surface topography of the skin is modeled using the Fresnel equations. The skin is treated as a three-layer material, with a mean-field treatment of tissue composition and related optical properties. The model, with a reasonable choice of tissue parameters, gives a remarkably accurate account of the features of actual measurements. It predicts the optimal values for the incident angle of the laser beam and the distance between ...


Radial Heterogeneity And Surface Properties Of Columns Used In High Performance Liquid Chromatography, Jude A. Abia 2010 University of Tennessee - Knoxville

Radial Heterogeneity And Surface Properties Of Columns Used In High Performance Liquid Chromatography, Jude A. Abia

Doctoral Dissertations

The radial heterogeneity of some columns used in high performance liquid chromatography (HPLC) was investigated using an on-column microelectrochemical amperometric detector. Such a detector allowed the recording of the elution profiles at different spatial positions throughout the column exit cross-section. From this, we obtain information about the radial distribution of the mobile phase velocity, column efficiency, and analyte concentration. In all cases, the results obtained show that the spatial distribution of the mobile phase velocity does not follow a piston-flow behavior but exhibits radial heterogeneity with differences not exceeding 5% between the center and wall regions of any column. The ...


Preparation Of Nitrogen Doped Nanostructured Tio2 And Its Applications To Photocatalytic Disinfection, Kainda Katembo Jr 2010 Clark Atlanta University

Preparation Of Nitrogen Doped Nanostructured Tio2 And Its Applications To Photocatalytic Disinfection, Kainda Katembo Jr

ETD Collection for AUC Robert W. Woodruff Library

No abstract provided.


Photocatalytic Inactivation Of Fungi With Tio2 With White Light And Different Buffer Systems, Aseelah Stoddard 2010 Clark Atlanta University

Photocatalytic Inactivation Of Fungi With Tio2 With White Light And Different Buffer Systems, Aseelah Stoddard

ETD Collection for AUC Robert W. Woodruff Library

The photocatalytic inactivation of fungi with P25 a mixed phase TiO2 material (25 % rutile and 75 % anatase) was examined using four fungal species: A. niger and M. racemosus, both spore forming fungi, and C. albicans and S. cerevisiae, yeast forming fungi. All four fungi species were found to be highly resistant to photocatalytic inactivation with P25 at room temperature under warm white light. The photocatalytic inactivation of fungi with P25 and alumina, in the presence of bicarbonate, chloride, phosphate, and silver were studied under warm white light to determine if these additives could enhance the inactivation activity. The addition of ...


Design, Synthesis And Spectroscopy Of Terpyridine Materials: From Energy And Charge Transfer To Chemosensor Applications, Victor O. Banjoko 2010 Clark Atlanta University

Design, Synthesis And Spectroscopy Of Terpyridine Materials: From Energy And Charge Transfer To Chemosensor Applications, Victor O. Banjoko

ETD Collection for AUC Robert W. Woodruff Library

The research presented in this dissertation focuses on the design, synthesis, photophysical characterization, and metal ion sensing properties of a conjugated polymer and enhancing the photophysical and acid-base properties of Ru(mtpy)(tpycooh)- a transition metal complex. All the synthesized compounds were based on terpyridine ligans. The objective of the first project is to investigate the effect of positioning the terpyridine unit in the meta position, which does not allow extended conjugation through the polymer backbone, on the metal ion sensing ability of this conjugated Poly(phenylenevinylene) (PPV) material. A novel PPV containing meta-linked pendant terpyridine ligand was synthesized. Absorption ...


Bunching Effect In Single-Molecule T4 Lysozyme Nonequilibrium Conformational Dynamics Under Enzymatic Reactions, Yuanmin Wang, H. Peter Lu 2010 Bowling Green State University

Bunching Effect In Single-Molecule T4 Lysozyme Nonequilibrium Conformational Dynamics Under Enzymatic Reactions, Yuanmin Wang, H. Peter Lu

Chemistry Faculty Publications

The bunching effect, implying that conformational motion times tend to bunch in a finite and narrow time window, is observed and identified to be associated with substrate enzyme complex formation in T4 lysozyme conformational dynamics under enzymatic reactions. Using single-molecule fluorescence spectroscopy, we have probed T4 lysozyme conformational motions under the hydrolysis reaction of polysaccharide of E. coli 13 cell walls by monitoring the fluorescence resonant energy transfer (FRET) between a donor acceptor probe pair tethered to T4 lysozyme domains involving open close hinge-bending motions. On the basis of the single-molecule spectroscopic results, molecular dynamics simulation, and a random walk ...


Production And In Vitro Investigation Of Vitamin B12-Based Bioprobes, Amy Rabideau 2010 Syracuse University

Production And In Vitro Investigation Of Vitamin B12-Based Bioprobes, Amy Rabideau

Syracuse University Honors Program Capstone Projects

Vitamin B12 (B12)-based bioprobes were produced and investigated in vitro for studying the B12 uptake pathway in certain cancer cell lines and their target-specific capabilities as imaging and/or contrast agents in vivo. An intrinsic factor (IF)-bound B12 conjugate (B12-ReBQBA) was produced containing rhenium(I) for in vitro analysis of the cubilin-expressing placental choriocarcinoma cell line. B12-ReBQBA has millimolar toxicity in vitro and excitation and emission wavelengths in the visible region, 488 nm and 560 nm, respectively. The rhenium metal in this bioprobe can be readily exchanged for the metastable ...


Chromatographic Studies Of Drug-Protein Binding In Diabetes, Kathryn (Krina) S. Joseph 2010 University of Nebraska - Lincoln

Chromatographic Studies Of Drug-Protein Binding In Diabetes, Kathryn (Krina) S. Joseph

Student Research Projects, Dissertations, and Theses - Chemistry Department

Drug-protein binding can have a dramatic impact on the distribution and metabolism of a drug. This manuscript describes the use of high-performance affinity chromatography to examine the binding of various compounds to human serum albumin (HSA) in normal and diabetic disease states.

The first study examined the use of four coumarin compounds as possible alternatives to warfarin as a probe for Sudlow site I on HSA. High-performance affinity chromatography and immobilized HSA columns were used to compare and evaluate the binding properties of these probe candidates. It was found from this group that 4-hydroxycoumarin was the best alternative to warfarin ...


Chemical Characterization Of Botanical Products: Comprehensive Speciation By Liquid Chromatography Particle Beam Mass Spectrometry, Joaudimir Castro georgi 2010 Clemson University

Chemical Characterization Of Botanical Products: Comprehensive Speciation By Liquid Chromatography Particle Beam Mass Spectrometry, Joaudimir Castro Georgi

All Dissertations

The dietary supplement industry has expanded and many of these supplements have become an important aspect of people's everyday lives. In 1994, the U.S. Dietary Supplement Health and Education Act (DSHEA) classified numerous nutraceutical/botanical products as dietary supplements because of their beneficial medicinal properties and provided the necessary regulation to the supplement producers. Since then, the interest of the scientific community towards dietary supplements has grown intensively and numerous studies have been carried out in order to understand the chemical behavior of the active molecules in the human body. The development towards analytical methods for the quantification ...


Diffusion Monte Carlo Studies Of Quantum Solvation: Finding Nodal Functions Of Wavefunctions Using A Genetic Algorithm, Christina Hansen Howell 2010 Utah State University

Diffusion Monte Carlo Studies Of Quantum Solvation: Finding Nodal Functions Of Wavefunctions Using A Genetic Algorithm, Christina Hansen Howell

Undergraduate Honors Capstone Projects

Solvation is important in many chemical reactions since most reactions occur in solution. Recently, progress has been made using helium-4 nanodroplets as the solvent at temperatures close to absolute zero. Because helium-4 is a superfluid it solvates dissolved molecules much differently that does a conventional solvent. This opens up the possibility of performing new types of chemistry in the superfluid environment. However, the nature of the interaction of the dissolved species with the solvent remains poorly understood. The basic question to be answered in this project is: how does the quantum solvent perturb the rotational dynamics of the solute particles ...


Terminal Deoxynucleotidyl Transferase: The Story Of A Misguided Dna Polymerase, Edward A. Motea, Anthony J. Berdis 2010 Case Western Reserve University

Terminal Deoxynucleotidyl Transferase: The Story Of A Misguided Dna Polymerase, Edward A. Motea, Anthony J. Berdis

Chemistry Faculty Publications

Nearly every DNA polymerase characterized to date exclusively catalyzes the incorporation of mononucleotides into a growing primer using a DNA or RNA template as a guide to direct each incorporation event. There is, however, one unique DNA polymerase designated terminal deoxynucleotidyl transferase that performs DNA synthesis using only single-stranded DNA as the nucleic acid substrate. In this chapter, we review the biological role of this enigmatic DNA polymerase and the biochemical mechanism for its ability to perform DNA synthesis in the absence of a templating strand. We compare and contrast the molecular events for template-independent DNA synthesis catalyzed by terminal ...


Molecular Design And Patterning Of Biosurfaces On Poly(Tetrafluoroethylene) (Ptfe), Nattharika Aumsuwan 2010 University of Southern Mississippi

Molecular Design And Patterning Of Biosurfaces On Poly(Tetrafluoroethylene) (Ptfe), Nattharika Aumsuwan

Dissertations

This dissertation describes the design, synthesis, and development of biocompatible poly(tetrafluoroethylene) (PTFE) surfaces that exhibit anti-microbial, anticoagulant, and dual functional surface properties. It consists of two parts: (1) design, synthesis, and analysis of antimicrobial and anti-coagulant PTFE surfaces, and (2) controllable micropatterning of anti-microbial and anti-coagulant species on the surface. PTFE was modified by Ar microwave plasma reactions in the presence of maleic anhydride, which upon hydrolysis creating COOH groups. These COOH primers were utilized as a platform for further surface reactions to attach polyethylene glycol (PEG) spacers, and penicillin (PEN) or ampicillin (AM) onto the PTFE surfaces. The ...


Synthesis, Characterization, And Deuterium Labeling Of Polyamides Studied By Nuclear Magnetic Resonance Spectroscopy, Christopher Allen Lange 2010 University of Southern Mississippi

Synthesis, Characterization, And Deuterium Labeling Of Polyamides Studied By Nuclear Magnetic Resonance Spectroscopy, Christopher Allen Lange

Dissertations

The synthesis, characterization, and deuterium labeling of polyamides have been investigated. In Chapter II, selective deuterium labeling of various polyamides was demonstrated via a facile method which does not require organic solvent or catalyst. Quantitative solution-state NMR analysis showed deuterium incorporation at the carbon alpha to the carbonyl ranged from 20-75%. Incorporation in ε-caprolactam increased with repeated treatments. Isotopic shift effects for the deuterated materials were additive for all sites within experimental error.

In Chapter III, the effect of stoichiometric imbalances on the polymerization of poly(dodecamethylene terephthalamide)was investigated. Molecular weight was varied by polymerizing the monomer salt with ...


Towards Multiplexed Electrogenerated Chemiluminescent Detection, Shijun Wang 2010 University of Southern Mississippi

Towards Multiplexed Electrogenerated Chemiluminescent Detection, Shijun Wang

Dissertations

The main objective of this dissertation is to understand and study the principle of electrogenerated chemiluminescence (ECL) and its applications to detect biomolecules simultaneously. Four aspects of ECL were studied. In order to carry out multiplexed ECL detection, both classical and several novel ECL systems have been investigated.

In the first aspect, significant effect of chloride ions on the ECL behavior of the tris(2,2′-bipyridyl) ruthenium(II) (Ru(bpy)3 2+)/tri-n-propylamine (TPrA) system at Au electrode was investigated. At low concentrations (e.g., [Cl-] < 5 mM), the ECL was enhanced; at relatively high concentrations, however, the ECL intensity decreased with the increase of the [Cl-]. At [Cl-] = 90 mM, ~ 50% and 100% ECL inhibition was observed for the first and the second ECL wave, respectively. The electrogenerated chloroaurate anions (AuCl2 - and AuCl4 -) which were verified using an electrochemical quartz-crystal microbalance (EQCM) method were found to be responsible for the ECL inhibition. This study suggests that care must be taken when Au working electrode is used for ECL studies in chloride-containing buffer solutions (widely used in DNA probes) and/or with the commonly used chloride-containing reference electrodes since in these cases the ECL behavior may significantly disagree with that obtained using other electrodes and reaction media.

In the second aspect, the electrochemical behavior of a trinuclear ruthenium(II)- containing ...


Aqueous Raft Synthesis Of Stimuli-Responsive, Amphiphilic Block Copolymers And Self-Assembly Behavior In Solution And Incorporation Into Lbl Films, Matthew Grady Kellum 2010 University of Southern Mississippi

Aqueous Raft Synthesis Of Stimuli-Responsive, Amphiphilic Block Copolymers And Self-Assembly Behavior In Solution And Incorporation Into Lbl Films, Matthew Grady Kellum

Dissertations

Of all the living radical polymerization techniques, reversible addition– fragmentation chain transfer (RAFT) polymerization is arguably the most versatile in terms of the reaction conditions (e.g. temperature and solvent selection), monomer selection (e.g. neutral, anionic, cationic, and zwitterionic), and purification. Since the introduction of RAFT in 1998, the McCormick research group and others including the Lowe, Sumerlin, and Davis research groups have synthesized a wide range of (co)polymers with predetermined molecular weights, low polydispersities, and advanced architectures utilizing aqueous RAFT (ARAFT) polymerization. These research groups have also studied how various block copolymers exhibit stimuli-responsive behavior due to ...


Multi Stimuli-Responsive Copolymers Obtained From Colloidal Dispersions, Fang Liu 2010 University of Southern Mississippi

Multi Stimuli-Responsive Copolymers Obtained From Colloidal Dispersions, Fang Liu

Dissertations

This dissertation describes the design, synthesis, and development of multi stimuli-responsive random copolymers that exhibit collective responsiveness to temperature, pH or electromagnetic radiation. New colloidal particles of poly(N-(DL)-(1- Hydroxyymethyl) propylmethacrylamide/n-butyl acrylate) (p(DL-HMPMA/nBA) and poly(2-(N,N′-dimethylamino)ethyl methacrylate/n-butyl acrylate) (p(DMAEMA/nBA)) were synthesized, which upon coalesce to form solid continuous films. The presence of lower glass transition (Tg) nBA components not only facilitate film formation, but also provide sufficient free volume for polymer chain rearrangements. These studies showed that coalesced films exhibit 3D dimensional changes upon external stimuli, which are ...


Studies On Heteroaromatic Schweinfurthin Analogues, John Gordon Kodet 2010 University of Iowa

Studies On Heteroaromatic Schweinfurthin Analogues, John Gordon Kodet

Theses and Dissertations

Natural products are a rich source of lead compounds for treatment of cancer as well as other diseases. Researchers at the National Cancer Institute, as part of their continuing effort to discover anticancer agents from natural sources, created the 60 human tumor cell-line anticancer screen to test natural products for their potential against various types of cancer. Through this screening process a family of natural products called schweinfurthins was discovered to possess potent and differential activity. Of potentially great significance, the pattern of activity that the schweinfurthins displayed in the screen does not correlate with any currently used anticancer drug ...


Synthesis Of Transition-Metal Polyphosphides, Brian Michael Barry 2010 University of Iowa

Synthesis Of Transition-Metal Polyphosphides, Brian Michael Barry

Theses and Dissertations

This dissertation describes the synthesis of several transition-metal polyphosphides including orthorhombic FePc2, cubic CoP3, cubic NiP2, monoclinic PdP2 and monoclinic CuP2. The investigation of these materials was initiated by the discovery of MPx formation upon reacting a metal halide with yellow P4 in superheated toluene. When these MPx products were annealed at moderate temperatures (350-500 °C), crystalline phosphorus-rich phases were afforded. Upon further investigation, we found that these phases have been primarily synthesized from high-temperature elemental reactions and that low temperature routes to these phase-pure polyphosphides using at least one non-elemental source ...


Solid-State Reactions In Co-Crystals: Applications In Synthetic Chemistry And Materials Science, Saikat Dutta 2010 University of Iowa

Solid-State Reactions In Co-Crystals: Applications In Synthetic Chemistry And Materials Science, Saikat Dutta

Theses and Dissertations

Chemistry is on the verge of a new era where the attention of chemists has shifted from covalent bonds to noncovalent interactions and their use as a predictable way to guide reactions pathways and product formation. Nature synthesizes elegant molecules under mild conditions and the designed syntheses have been demonstrated to be largely dependent on recognition, self-assembly and templating effects between molecular building blocks. Although covalent synthesis in fluidic medium via supramolecular control has been achieved with limited success, organic solid state has been of particular interest since it avoids solvent effects, and is able to provide unique materials with ...


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