Chemistry Commons^™

Mixed Lineage Leukemia Histone Methylases In Gene Expresion And Cancer, Bibhu Prasad Mishra

Chemistry & Biochemistry Dissertations - Archive

Histone methyl-transferases (HMTs) are key enzymes that post-translationally methylate nuclear histone proteins and play critical roles in gene expression, epigenetic regulation and diseases in eukaryotic organisms. Mixed lineage leukemias (MLLs) are human HMTs that specifically methylate histone H3 at lyisine-4 and regulate gene activation. MLLs are also well known to undergo rearrangement often in acute myeloid and lymphoid leukemias. Human encodes several histone H3 lysine-4 (H3K4) specific methyl-transferases (HMTs) such as MLL1 (mixed lineage leukemia gene 1), MLL2, MLL3, hSet1 etc, which play critical roles in gene expression. These HMTs are present as distinct multi-protein complexes with several proteins in …

Design And Synthesis Of A High Potential Ruthenium (Ii) Tetraazatetrapyridopentaphene Complex Capable Of Two-Electron Reduction, Nancy Ruth G. Diaz

Chemistry & Biochemistry Theses - Archive

We report the synthesis of a complex, [(phen)₂Ru(tatpph)Ru(phen)₂]⁴⁺ (Ph⁴⁺), which like its predecessor compound, [(phen)₂Ru(tatppc)Ru(phen)₂]⁴⁺ (Pc ⁴⁺), can undergo two sequential 1-electron photoreductions in MeCN in the presence of a sacrificial reductant. The initial complex, Ph ⁴⁺, can be completely regenerated from the singly and doubly reduced forms by exposure to air, although the rate of regeneration for the second photoreduction is much slower than the first. Electrochemical studies have shown that this complex is not only capable of storing multiple reducing equivalents but these equivalents have stored potentials that are significantly higher than the complex Pc ⁴⁺ and are …

The Effects Of Buckminster Fullerenes On Mitochondrial Function, Sara Rosario

Undergraduate Honors Theses

Since the discovery of Buckminster Fullerenes (C60), this carbon nanoparticle has been the subject of intense study. C60 has been investigated in such applications as photodynamic therapy of cancer, photovoltaic cells, semiconductors, and enzyme inhibition. Despite two decades of research, the biological effects of C60 remain a mystery. The intention of this study was to examine the effects of Buckminster Fullerenes on mitochondrial function in an effort to determine the concentration of C60 as well as the time frame of exposure that causes maximum dysfunction. Thus, bovine heart mitochondria were exposed to different doses of C60 (2 -35 ppm). To …

A Simple Sn2 Reaction For The Undergraduate Organic Laboratory, John J. Esteb

Scholarship and Professional Work - LAS

A simple procedure for the synthesis of n-butyl naphthyl ether is presented. This procedure represents an easy method for the production of an aryl ether by an SN2 reaction, uses ethanol as an environmentally friendly solvent, and does not require the use of a lachrymator. Product isolation is done by pouring the reaction mixture over ice and collecting the solid by suction filtration. Students typically recover from 7–95% of the ether.

A Flexible Solvolysis Experiment For The Undergraduate Organic Laboratory, John J. Esteb, John R. Magers, Luanne M. Mcnulty, Paul Morgan

Scholarship and Professional Work - LAS

A simple SN1 reaction is presented that uses bromotriphenylmethane and a range of oxygen-based nucleophiles including water and various alcohols. This procedure represents a process that affords easy isolation of solid products. Typical student yields ranged from 17–128% with the average yield of 50%. Students obtained products with a melting point range of 140 to 164 °C. This procedure offers multiple ways to adapt this experiment from a straight solvolysis reaction to a discovery-based experiment that explores the effect of nucleophile (for a more advanced group) or the method of product isolation.

Resolution Modeling Of Length Tuning In Gas Chromatography, James P. Grinias

Senior Honors Theses and Projects

Tunable selectivity provides a relatively simple and inexpensive way to manipulate peak positions and gain resolution in chromatographic separations. Length tuning utilizes two columns of different polarities connected in series. Selectivity is manipulated by changing the relative lengths of the two columns. However, a direct correlation is not seen between relative length and effective contribution due to gas compression effects. Rather, a direct correlation is observed between the carrier gas transport time through a segment of column (relative to the total carrier gas transport time) and the effective contribution of that segment. This relationship has been used to predict retention …

A Chemical Ionization Mass Spectrometer For Continuous Underway Shipboard Analysis Of Dimethylsulfide In Near-Surface Seawater, Eric S. Saltzman, Warren J. De Bruyn, M. J. Lawler, Christa Marandino, C. A. Mccormick

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

A compact, low-cost atmospheric pressure, chemical ionization mass spectrometer ('mini-CIMS') has been developed for continuous underway shipboard measurements of dimethylsulfide (DMS) in seawater. The instrument was used to analyze DMS in air equilibrated with flowing seawater across a porous Teflon membrane equilibrator. The equilibrated gas stream was diluted with air containing an isotopically-labeled internal standard. DMS is ionized at atmospheric pressure via proton transfer from water vapor, then declustered, mass filtered via quadrupole mass spectrometry, and detected with an electron multiplier. The instrument described here is based on a low-cost residual gas analyzer (Stanford Research Systems), which has been modified …

Ionization Competitors Extend The Linear Range Of Electrospray Ionization Mass Spectrometry, Bilal H. Bazzi

Chemistry & Biochemistry Theses - Archive

ESI-MS has proven its applicability in quantitative analysis for a wide range of analytes. Its effectiveness relies on achieving sensitivity and linear range, although the latter is known to be limited. ESI-MS response varies among charged species due to differences in analyte structure. The working curve associated with quantitative analysis has a limit of linearity. At high analyte concentration, instrument response plateaus because the surface of the charged droplet reaches saturation. Several studies have proposed to enhance the linear range by enhancing gas-phase analyte charging, by facilitating droplet evaporation, or by improving ion transmission through the mass spectrometer. This thesis …

Enantiomeric Separation, Microorganism Studies And Determination Of Binding Constants Using Capillary Electrophoresis, Chunxia Jiang

Chemistry & Biochemistry Dissertations - Archive

Enantiomeric separation of three series of compounds, including β-lactams, synthetic amino acids and ruthenium(II) polypyridyl complexes using different modes of capillary electrophoresis are discussed in this dissertation. Enantiomeric recognition mechanisms are explored by studying the effect of the structures of chiral selectors and analytes. Results indicated that the size correlation between the analyte and the cyclodextrin cavity size play an important role in enantioseparation. Effects of experimental parameters including chiral selector concentration, buffer additive type and concentration, run buffer pH and applied voltage are studied for optimization of the enantioseparations. A new class of chiral selectors, cyclofructans were developed and …

Studies Of Enantiomeric Separations Using Capillary Electrophoresis, Man-Yung Benjamin Tong

Chemistry & Biochemistry Theses - Archive

The focus of this thesis is on using state-of-the-art capillary electrophoresis (CE) in enantiomeric separations. Chapter 1 provides a brief introduction to enantiomeric separations using CE. Chapters 2 through 5 presents the use of different novel chiral selectors in CE. The selector properties and strategies for developing on enantiomeric separations are considered. Chapter 2 presents an overview on the most broadly useful chiral selectors for CE enantiomeric separations, sulfated cyclodextrins. Chapter 3 presents a new chiral selector, sodium arsenyl L-(+) tartrate. This chiral selector shows enantioselectivity for many amine-containing compounds and ruthenium (II) polypyridyl complexes and produces electropherograms with short …

Synthesis Of The Bicyclic Core Of Pyrrolizidine Alkaloids, Fatmagul Tuluoglu

Master's Theses and Doctoral Dissertations

Pyrrolizidine alkaloids are a large class of natural products whose members exhibit a variety of biological properties including potential applications toward the treatment of cancer, diabetes, and viral infections such as HIV. In addition, some of these compounds exhibit insect antifeedant activity, and so have potential applications in the agricultural industry for the protection of crops.

For these reasons, we were interested in developing a method to form the bicyclic alkaloid core that could be functionalized to generate many pyrrolizidine alkaloids. Specifically, our goal was to synthesize the pyrrolizidine B-ring by a novel McMurry cyclization strategy (Scheme 1). The synthesis …

Development Of Methodology For The Use Of Multi-Bed Sorbent Traps With Gas Chromatography Time Of Flight Mass Spectrometry, Siva Maheswara Reddy Anna Pareddy

Master's Theses and Doctoral Dissertations

The lipid peroxidation of unsaturated fatty acids in cellular membranes leads to the formation of alkanes, aldehydes, alkanals, alk-2-enals, and hydroxyl alkenals. The free radicals formed during the process of lipid peroxidation can react with and damage cellular components. Lipid peroxidation is known to cause a number of diseases such as cancer, diabetes, and heart disease. Various analytical methods that include spectrometric assays and chromatographic analyses of derivatized products are available for the detection of the lipid peroxidation products.

The development of rapid, non-invasive monitoring of reactions occurring in biological systems, such as cell cultures, is highly desirable, as such …

Influence Of Magnesium Nitrate On The Corrosion Performance Of Sol-Gel Coated Aa2024-T3 Aluminium Alloy, Rajath Varma, Brendan Duffy, John Cassidy

Articles

Traditional anti-corrosion technology has relied heavily on using reducible metal species, predominantly hexavalent chromium (Cr(VI)), for protecting reactive metal alloys such as aluminium which is extensively used in the aerospace sector. However, the impending changes in the use of Cr(VI) in Europe and the United States have forced aerospace manufacturers to examine alternative materials for protecting aluminium. One of the most promising alternatives being investigated are organosilane based sol-gels containing anticorrosion additives. In this work the anti-corrosion properties of magnesium (II) nitrate (Mg(NO3)2) as a inhibitor was investigated at different concentrations (0.1% - 1.0 wt %) in a methyltriethoxysilane (MTEOS) …

Electrodeposition Of Inorganic Materials With Tailored Shapes And Chiral Morphologies, Elizabeth A. Kulp

Doctoral Dissertations

"This dissertation investigates the electrodeposition of metal oxide films and biomaterial deposits on polycrystalline and single crystal substrates. Paper I describes the mechanisms and the characterization of an electrodeposited polycrystalline insulator, ceria (CeO₂), on Hastelloy substrates produced by the electrochemical oxidation of Ce(III) acetate complexes. In Paper II, epitaxial films of magnetite (Fe₃O₄) and ferrihydrite (Fe₁₀O₁₄(OH)₂) are deposited on gold single crystals. Paper III reports the electrodeposition of epitaxial Fe₃O₄ and zinc ferrite (ZnFe₂O₄) periodic nanostructures known as superlattices by pulsing between two potentials. Papers IV and V describe chiral electrodeposition. In Paper IV, epitaxial, chiral orientations of cupric oxide …

Capillary Electrophoresis Based Microbial Detection And Separation, Ryan Nelson, Andrew Lantz

Student Summer Scholars Manuscripts

Capillary Electrophoresis (CE) represents a significant tool for the separation of microorganisms as well as the detection and isolation of Candida albicans (CA) fungus in human blood. There currently exists few rapid means by which biological pathogens can be tested, at low concentration, in blood, and other organic matrices. Other common chromatographic techniques, such as GC, HPLC, IR and MS do not have the capability of analyzing living microorganisms, nor the ability to separate them with any precision. CE offers the rare opportunity to separate individual cells by the charge to size ratio as well as their isoelectric focusing point …

Conversion Of Cellulose To Value Added-Chemicals, Shane Mcgrath, Dalila Kovacs, Jim Krikke

Student Summer Scholars Manuscripts

Biomass-derived feedstock is of growing importance in the development of new synthetic pathways for commodity and specialty chemicals. Utilizing basic catalytic concepts such as hydrolysis, dehydration, isomerisation, and other common transformations of sugar in biomass conversion has already produced significant advances in the fundamental understanding of biomass conversion.

Despite the progress that has already been made, very few studies are dedicated to understanding the fundamentals of cellulose conversion under heterogeneous catalytic conditions. This is due to the complexity of both the catalytic steps at the metal/support interface and the structure of cellulose itself, being a highly functionalized homopolymer, characterized by …

The Tata-Binding Protein Core Domain In Solution Variably Bends Tata Sequences Via A Three-Step Binding Mechanism [Tables & Figures], Roberto F. Delgadillo, Jodell E. Whittington, Laura K. Parkhurst, Lawrence J. Parkhurst

Lawrence Parkhurst Publications

Studies of the binding and bending of the AdMLP TATA sequence (TATAAAAG) by the core domain of yeast TBP allow quantitation of the roles of the N-terminal domains of yeast and human TBP. All three proteins bind DNA via a three-step mechanism with no evidence for an initially bound but unbent DNA. The large enthalpy and entropy of activation for the first step in yTBP binding can now be assigned to movement of the NTD from the DNA binding pocket and not to energetics of DNA bending. The energetic patterns for hTBP and cTBP suggest that the …

Open Ocean Dms Air/Sea Fluxes Over The Eastern South Pacific Ocean, C. A. Marandino, Warren J. De Bruyn, S. D. Miller, E. S. Saltzman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Air/sea fluxes of dimethylsulfide (DMS) were measured by eddy correlation over the Eastern South Pacific Ocean during January 2006. The cruise track extended from Manzanillo, Mexico, along 110 degrees W, to Punta Arenas, Chile. Bulk air and surface ocean DMS levels were also measured and gas transfer coefficients (k(DMS)) were computed. Air and seawater DMS measurements were made using chemical ionization mass spectrometry (API-CIMS) and a gas/liquid membrane equilibrator. Mean surface seawater DMS concentrations were 3.8 +/- 2.2 nM and atmospheric mixing ratios were 340 +/- 370 ppt. The air/sea flux of DMS was uniformly out of the ocean, with …

The Biochemical Reactions Of Dry State Dna, April Marrone

Electronic Theses and Dissertations

The biochemistry of dry state DNA is of interest to the fields of forensics, ancient DNA, and DNA storage. The exact chemical nature of the degradation of the DNA molecule in the dry state has not been studied prior. If determined what chemical changes the DNA molecule undergoes, to what degree and in what time frame then protocols can be implemented to bypass the impact of this damage or to repair it when necessary. It is suspected that similar reactions occur to the dry state DNA molecule as does to the hydrated molecule. It cannot be assumed, however that these …

Application Of Alkylsilane Self-Assembled Monolayers For Cell Patterning And Development Of Biolocial Microelectromechanical Systems, Kerry Wilson

Electronic Theses and Dissertations

Advances in microfabrication and surface chemistry techniques have provided a new paradigm for the creation of in vitro systems for studying problems in biology and medicine in ways that were previously not practical. The ability to create devices with micro- to nano-scale dimensions provides the opportunity to non-invasively interrogate and monitor biological cells and tissue in large arrays and in a high-throughput manner. These systems hold the potential to, in time, revolutionize the way problems in biology and medicine are studied in the form of point-of-care devices, lab-on-chip devices, and biological microelectromechanical systems (BioMEMS). With new in vitro models, it …

Scorpionate Supported And Unsupported Carbonyl And Ethylene Complexes Of Group 11 Metals, Mauro Fianchini

Chemistry & Biochemistry Dissertations - Archive

Carbon monoxide (CO) and small olefins represent perhaps the simplest, but most important ligand systems in coordination/organometallic chemistry. Simple carbonyl and ethylene compounds have started to appear in the field since the early nineteen century. Due to their peculiar electronic properties, strong bonds to late transition metal cations such as Cu¹, Ag¹, and Au¹ are generally discouraged. However, intermediates involving M-CO or M-olefin (where M = Cu¹, Ag¹, Au¹) have been claimed to be key-steps in reactions and industrial processes involving coinage metals. Unfortunately, experimental data on coinage metal complexes with CO and olefins are scarce due to the difficulty …

Enantiomeric Separations And New Chiral Stationary Phases, Chunlei Wang

Chemistry & Biochemistry Dissertations - Archive

Chirality is an important concern for biological activity because asymmetry dominates biological processes at a molecular level. After nearly thirty years of development, liquid chromatographic separations on chiral stationary phases (CSPs) have become the state-of-art technology for resolution of enanantiomeric compounds. However, with the trend in the pharmaceutical industry to replace racemate drugs with their single enantiomer forms, chiral methods are in ever increasing demand. The efficient development of enantiomeric separation methods is still challenging and time consuming. In this thesis, we present new approaches for the enantiomeric separation of two important pharmaceutical compounds, the development of three new CSPs, …

Application Of Multiple Mass Spectrometric Techniques In The Isolation, Determination And Characterisation Of The Marine Toxins; Azaspiracid, Keith O'Callaghan

Theses

The Azaspiracids are a class of polyether marine biotoxins that present a significant health risk to consumers of shellfish. Since their discovery in the late 1990s several human intoxications have been reported, and traced to Irish shellfish farms resulting in closures or harvest rejections. As such incidents involving azaspiracid shellfish poisoning have a major socio-economic impact on communities that rely on shellfish farming revenues.

Recent evidence suggests that azaspiracid poisoning events may become more commonplace. With this increased risk the understanding of azaspiracids mode of action and biological targets becomes crucial. To support these endeavours effective analytical methods need to …

Earth's Heat Source -- The Sun, Oliver Manuel

Chemistry Faculty Research & Creative Works

The Sun encompasses planet Earth, supplies the heat that warms it, and even shakes it. The United Nation's Intergovernmental Panel on Climate Change (IPCC) assumed that solar influence on Earth's climate is limited to changes in solar irradiance and adopted the consensus opinion of a hydrogen-filled Sun - the Standard Solar Model (SSM). They did not consider the alternative solar model and instead adopted another consensus opinion: Anthropogenic greenhouse gases play a dominant role in climate change. The SSM fails to explain the solar wind, solar cycles, and the empirical link of solar surface activity with Earth's changing climate. The …

Carnot Cycles: Traditional And Stefan Boltzmann, And The First Planck Argument, Carl W. David

Chemistry Education Materials

The Stefan Boltzmann equation is obtained using a non-traditional Carnot Engine. In addition, the original Planck argument for radiation density is given.

Lee O. Case's "Elements Of The Phase Rule", Chapter 1, One Component Systems, Carl W. David

Chemistry Education Materials

One component systems are treated from the point of view of the Gibbs' phase rule.

Lee O Case's "Elements Of The Phase Rule", Chapter 3, Carl W. David

Chemistry Education Materials

This is the last (third) chapter of the phase rule text, again altered by the author, addressing 3 and 4 compnent systems.

Platforms And Protocols For The Multidimensional Microchip Electrophoretic Analysis Of Complex Proteomes, John K. Osiri

LSU Doctoral Dissertations

The need for rapid, portable and high-throughput systems in proteomics is now prevalent because of demands for generating new protein-based disease biomarkers. However, 2-D protein profile patterns are lending themselves as potential diagnostic tools for biomarker discovery. It is difficult to identify protein biomarkers which are low abundant in the presence of highly abundant proteins, especially in complex biological samples like serum. Protein profiles from 2-D separation of the protein content of cells or body fluids, which are unique to certain physiological or pathological states, are currently available on internet databases. In this work, we demonstrate the ability to separate …

Studies Of Homogeneous Dirhodium Catalyst System, Catherine L. Thomas Alexander

LSU Doctoral Dissertations

Hydroformylation studies were conducted to investigate the effects of various H&sub2;/CO ratios on rac-[Rh&sub2;H&sub2;(μ-CO)&sub2;(et,ph-P4)]²+;, a dirhodium tetraphosphine catalyst system. Similar experiments were also conducted with monometallic catalysts based on BISBI, NAPHOS, and Xantphos, some of the best bisphosphine ligands for hydroformylation catalysis. This was due to the lack of information in literature on the effects of variable ratios and pressures on activities and selectivities of catalysts that contain bisphosphine ligands, and these studies were also used as a basis of comparison for the dirhodium system. Results indicate that the dirhodium system is more efficient with higher H&sub2;/CO ratios (2:1, 90 …

Single-Molecule Detection Of Unique Genome Signatures: Applications In Molecular Diagnostics And Homeland Security, Jason M. Emory

LSU Doctoral Dissertations

Single-molecule detection (SMD) offers an attractive approach for identifying the presence of certain markers that can be used for in vitro molecular diagnostics in a near real-time format. The ability to eliminate sample processing steps afforded by the ultra-high sensitivity associated with SMD yields an increased sampling pipeline. When SMD and microfluidics are used in conjunction with nucleic acid-based assays such as the ligase detection reaction coupled with single-pair fluorescent resonance energy transfer (LDR-spFRET), complete molecular profiling and screening of certain cancers, pathogenic bacteria, and other biomarkers becomes possible at remarkable speeds and sensitivities with high specificity. The merging of …