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Full-Text Articles in Physical Sciences and Mathematics

Synthesis And Antimicrobial Activity Of Brominated Quaternary Ammonium Compounds, Wendy Pippin Aug 2014

Synthesis And Antimicrobial Activity Of Brominated Quaternary Ammonium Compounds, Wendy Pippin

Honors Theses

No abstract provided.


Synthesis And Functionalization Of Bodipy Dyes For Applications In The Detection Of Colorectal Cancer, Logan Elise Leblanc May 2014

Synthesis And Functionalization Of Bodipy Dyes For Applications In The Detection Of Colorectal Cancer, Logan Elise Leblanc

Honors Theses

No abstract provided.


Controlling Competing Phases Of Magnetic Intermetallics And Bioceramics, Jacob D. Mcalpin Apr 2014

Controlling Competing Phases Of Magnetic Intermetallics And Bioceramics, Jacob D. Mcalpin

Honors Theses

No abstract provided.


Synthesis And Analysis Of Copper Beta-Diketonate Complexes, Jonathan Stephen Casey Jan 2014

Synthesis And Analysis Of Copper Beta-Diketonate Complexes, Jonathan Stephen Casey

LSU Master's Theses

This research addresses the synthesis and characterization of Cu(II) complexes of silicon-based multidentate β-diketonate ligands. The possible products of the synthesis include (where L represents the coordinated ligand) cube Cu12L8, decahedron Cu24L16, and dodecahedron Cu30L20. This study aims to determine the structure of these discrete molecules, which may have applications in drug delivery, fuel storage, and chemical retention. Different techniques were involved in the characterization of Cu(II) complexes: Electrospray Ionization Time of Flight Mass Spectrometry (ESI-TOF MS), Atomic Force Microscopy (AFM) and Analytical Ultracentrifugation (AUC). In ESI-TOF MS, the exact mass of the molecules was attempted to be determined by …


Expression Of O-Linked N-Acetylglucosamine Modified Proteins And Production And Characterization Of Chlamydia Trachomatis Ct663, Octavia Y. Goodwin Jan 2014

Expression Of O-Linked N-Acetylglucosamine Modified Proteins And Production And Characterization Of Chlamydia Trachomatis Ct663, Octavia Y. Goodwin

LSU Doctoral Dissertations

O-linked â-N-acetylglucosamine is a regulatory post translational modification. This modification occurs on nearly all functional classes of proteins, in the nucleus and cytoplasm. O-GlcNAc is added to serine or threonine by O-GlcNAc transferase and removed by O-GlcNAcase. Previous attempts to study O-GlcNAc-modified proteins have resulted in low yields, making 3-dimensional structure determination impossible. In this dissertation O-GlcNAc transferase will be co-expressed with domains of human cAMP responsive element-binding protein (CREB1) and Abelson tyrosine-kinase 2 (ABL2) in E. coli, to produce O-GlcNAc-modified protein. The O-GlcNAc-modified protein was expressed in a variety of E. coli cell lines at a variety of conditions, …


Synthesis, Characterization, And Investigation Of The Catalytic Activity Of Nio, Cuo, And Nio-Cuo Nanoparticles On Silica As Surrogates Of Combustion-Generated Nanoparticles, Nuwan Nilanka Balapitiya Liyanage Jan 2014

Synthesis, Characterization, And Investigation Of The Catalytic Activity Of Nio, Cuo, And Nio-Cuo Nanoparticles On Silica As Surrogates Of Combustion-Generated Nanoparticles, Nuwan Nilanka Balapitiya Liyanage

LSU Doctoral Dissertations

Transition metal oxide nanoparticles contained in fly ash are known to catalyze the formation of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) during the waste incineration process. The potential catalytic activity of silica-supported NiO, CuO, and NiO-CuO nanoparticles for the formation of PCDD/Fs will be discussed in this dissertation. The successful synthesis of silica-supported NiO, CuO, and NiO-CuO nanoparticles as surrogates of combustion-generated nanoparticles was important to this study. The synthesis was followed by the characterization of the nanoparticle surrogates by X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDS). Finally, the catalytic …


Application Of Scanning Probe Microscopy To Characterize Physical Properties Of Polymer Brushes, Photoactive Polymers And Rare Earth Oxide Nanostructures, Susan Denise Verberne-Sutton Jan 2014

Application Of Scanning Probe Microscopy To Characterize Physical Properties Of Polymer Brushes, Photoactive Polymers And Rare Earth Oxide Nanostructures, Susan Denise Verberne-Sutton

LSU Doctoral Dissertations

A sample stage for characterizing photoactive materials was developed for studies with scanning probe microscopy (SPM). A sample stage was designed that directs light from a solar simulator via a fiber optic cable to illuminate the sample. Current-sensing and photocurrent measurements can be acquired with a conductive tip. The designed photocurrent stage can be used for SPM systems with a tip-mounted scanner. Current-sensing measurements can be taken with or without illumination to measure the current produced from organic photovoltaic (OPV) or photoconductive samples. Topography, lateral force and current-sensing images are acquired simultaneously, providing information of how nanoscale morphology affects the …


Bio-Imprinted Hydro-Gels (Bigs) For Protein And Virus Detection, Wei Bai Jan 2014

Bio-Imprinted Hydro-Gels (Bigs) For Protein And Virus Detection, Wei Bai

LSU Doctoral Dissertations

Detection of bio-markers at low concentration is becoming a more and more important topic in scientific research due to its importance in applications crucially related to people’s life like medical diagnosis, environment protection and national security. In the past decades, as the improvement of the modern analytical technologies progressed, plenty of methodologies have been developed to realize the fast and accurate detection of bio-markers in liquid media. However, some drawbacks still remain like the expensive cost, high requirement of operational environment, and need for skilled operators. Here, a new kind of aptamer-based bio-imprinted hydrogel sensor (BIG) with specific macroscopic volume …


Characterization Of A Water Soluble, Non-Ionic, Helical Poly(Α-Amino Acid), Wayne Huberty Jan 2014

Characterization Of A Water Soluble, Non-Ionic, Helical Poly(Α-Amino Acid), Wayne Huberty

LSU Doctoral Dissertations

A water soluble, non-ionic, rodlike polymer, PEGL, was synthesized and characterized in efforts to synthesize a novel model polymer to study stiff polymers in solution. The rodlike system is likely stiff due to a high relative percent helicity in water up to 50 °C, measured by circular dichroism, the observation of liquid crystalline domains in water, and from the slope measured from conformation plots supplied by GPC/MALS; however, it also apparent the system is aggregating in both a 2 mM azide solution and a buffer (200 mM NaNO3 + 20 mM NaH2PO4 + 2 mM NaN3), in corroboration of negative …


Design, Synthesis, And Evaluation Of Small Molecule-Based, Profluorogenic Activatable Substrate Probes For Detection And Visualization Of Human Cancer Enzyme Nad(P)H:Quinone Oxidoreductase-1, Suraj Uditha Hettiarachchi Jan 2014

Design, Synthesis, And Evaluation Of Small Molecule-Based, Profluorogenic Activatable Substrate Probes For Detection And Visualization Of Human Cancer Enzyme Nad(P)H:Quinone Oxidoreductase-1, Suraj Uditha Hettiarachchi

LSU Doctoral Dissertations

Cancer comprises many specific diseases, and it is currently responsible for millions of deaths worldwide. This broad disease profile is a great challenge for personalized oncology. Critical for the success of cancer therapy is the exploration of improved methodologies for the early detection of localized and disseminated tumor cells in patients, where bio-molecular imaging has become an indispensable tool. Being one of many different imaging techniques, optical fluorescence imaging has been translated over the years from the bench to clinical research, and it is now on the verge of being able to address some of the pressing challenges in molecular …


Gumbos- And Ionic Liquid-Coated Quartz Crystal Microbalance Sensors For Detection And Molecular Weight Determination Of Organic Vapors, Bishnu Prasad Regmi Jan 2014

Gumbos- And Ionic Liquid-Coated Quartz Crystal Microbalance Sensors For Detection And Molecular Weight Determination Of Organic Vapors, Bishnu Prasad Regmi

LSU Doctoral Dissertations

There has been an ever-increasing demand for the development of high-performance sensing devices for detection and discrimination of volatile organic compounds (VOCs) present in different environments. Among a number of sensing devices currently available, sorption-based sensors are particularly attractive because they are simple and inexpensive, require low power, and are appropriate for fabrication of multisensor arrays. A sorption-based sensor is comprised of a chemically active coating immobilized on the surface of a physical transducer. The chemically active film interacts with analytes, and the transducer converts the binding event into an electrical signal. This dissertation is focused on a sorption-based sensor …


Synthesis, Characterization, And Evaluation Of Novel Bodipy Dyes With Theranostic Applications, Jaime Suzanne Hayes Jan 2014

Synthesis, Characterization, And Evaluation Of Novel Bodipy Dyes With Theranostic Applications, Jaime Suzanne Hayes

LSU Doctoral Dissertations

Boron dipyrromethene (BODIPY) dyes, have garnered much attention in recent decades due to their enticing photophysical properties and their bioimaging applicability. Despite the progression of this field, the development of BODIPY based anti-cancer agents and radioimaging dyes has seen little progress. The utilization of fluorescent BODIPYs as photosensitizers for photodynamic therapy, and as boron delivery agents for boron neutron capture therapy offers promise as theranostic agents. Additionally, BODIPY derivatives that absorb and emit in the near-IR regions of the electromagnetic spectrum and bear radioisotopes suitable for radioimaging techniques are of great interest. Chapter 1 is a concise overview of the …


Ionic Liquids And Gumbos For Biomedical And Sensing Applications, Paul Kipkorir Sang Magut Jan 2014

Ionic Liquids And Gumbos For Biomedical And Sensing Applications, Paul Kipkorir Sang Magut

LSU Doctoral Dissertations

This dissertation is a synopsis of advancements in the field of ionic liquids and a group of uniform materials based on organic salts (GUMBOS) in biomedical applications, especially with regard to cancer research. The toxicity of chemotherapeutic agents to normal tissues and drug resistance are a major concern in cancer treatment. In this dissertation, GUMBOS and nanoGUMBOS as well as ionic liquids and nanodroplets are explored as possible chemotherapeutic agents with minimal toxicity to normal cells. In the first part of my dissertation, exploitation of ionic liquid chemistry to modulate toxicity of rhodamine 6G is reported. Rhodamine 6G-based GUMBOS with …


Polymer Micro- And Nanofluidic Systems For In Vitro Diagnostics: Analyzing Single Cells And Molecules, Swathi Reddy Pullagurla Jan 2014

Polymer Micro- And Nanofluidic Systems For In Vitro Diagnostics: Analyzing Single Cells And Molecules, Swathi Reddy Pullagurla

LSU Doctoral Dissertations

Polymer micro- and nanofluidic systems, with their critical dimensions, offer a potential to outperform conventional analysis techniques and diagnostic methods by enhancing speed, accuracy, sensitivity and specificity. In this work, applications of microfluidics have been demonstrated to address the existing challenges in stroke diagnosis, by mRNA expression profiling from whole blood within <20 min. A brief overview of various biomarkers for stroke diagnosis is given in chapter 1 followed by design and testing of individual microfluidic modules (chapter 2 and 3) required for the development of POC diagnostic strategy for stroke. We have designed and evaluated the performance of polymer microfluidic devices for the isolation of leukocyte subsets, known for their differential gene expression in the event of stroke. Target cells (T-cells and neutrophils) were selected from with greater purities, from 50 µl whole human blood by using affinity based capture in COC devices within a 6.6 min processing time. In addition, we have also demonstrated the ability to isolate and purify total RNA by using UV activated polycarbonate solid phase extraction platform. Polymer-based nanofluidic devices were used to study the effects of surface charge on the electrodynamic transport dynamics of target molecules. In this work, we report the fabrication of mixed-scale micro- and nanofluidic networks in poly(methylmethacrylate), PMMA, using thermal nanoimprint lithography using a resin stamp and surface modification of polymer nanoslits and nanochannels for the assessment of the associated electrokinetic parameters – surface charge density, zeta potential and electroosmotic flow. This study provided information on possible routes that can be adopted to engineer proper wall chemistry of polymer nanochannels for the enhancement or reduction of solute/wall interactions in a variety of relevant single-molecule studies.


Improved Synthesis, Separation, Transition Metal Coordination And Reaction Chemistry Of A New Binucleating Tetraphosphine Ligand, Ekaterina Kalachnikova Jan 2014

Improved Synthesis, Separation, Transition Metal Coordination And Reaction Chemistry Of A New Binucleating Tetraphosphine Ligand, Ekaterina Kalachnikova

LSU Doctoral Dissertations

The first chapter of this dissertation involves discussion of alkene hydration and oxidative cleavage reactions catalyzed by late transition metal complexes. Previously reported results are summarized here. Mechanistic aspects of alkene hydration catalyzed by late transition metal complexes are also explained. The second part of Chapter 1 focuses on motivation for using bimetallic nickel phosphine complexes as possible catalytic precursors for alkene hydration. Chapter 2 describes studies into alkene hydration in the presence of catalytic amounts of dinickel phosphine complexes based on linear tetraphosphine ligand, PEt2CH2CH2(Ph)PCH2P(Ph)CH2CH2PEt2, et,ph-P4. Under conditions tested no alcohol products were detected. However we have observed formation …


“Trans-Positioning” Carbons Within Strained Caged Bicyclic(S): Rom/Rcm (Ring-Opening/Ring-Closing) Metathesis And Dieckmann/Retro-Dieckmann Condensation Routes To A Cis-Decalin Infrastructure, Stefan Malone Cooper Jr Jan 2014

“Trans-Positioning” Carbons Within Strained Caged Bicyclic(S): Rom/Rcm (Ring-Opening/Ring-Closing) Metathesis And Dieckmann/Retro-Dieckmann Condensation Routes To A Cis-Decalin Infrastructure, Stefan Malone Cooper Jr

LSU Doctoral Dissertations

This dissertation describes methodology work involving a “Trans-Positioning” motif engaging strategically positioned carbons within a strained bi-carbocyclic core and on a tethered free-dangling hydrocarbon chain ultimately for skeletal rearrangement. Trans-alkenylation and trans-acylation processes are devised for investigation with bicyclo[2.2.2]octyl and bicyclo[2.2.1]heptyl strained cores. Recent advances in olefin metathesis led to an independent proposal of the now applicable, RRM (Ring-Rearranging Metathesis) for trans-alkenylation purposes. A resourceful Dieckmann/retro-Dieckmann sequence is devised for trans-acylation motives. Finally, this dissertation includes atypical diastereoselective reductions and additions which were serendipitously found with trigonal carbon atoms appended to our pertinent strained systems while in pursuit of our …


Syntheses And Characterization Of Isoporphyrins And Bodipys For Pdt And Imaging, Haijun Wang Jan 2014

Syntheses And Characterization Of Isoporphyrins And Bodipys For Pdt And Imaging, Haijun Wang

LSU Doctoral Dissertations

This Dissertation is divided into five chapters reporting various aspects of the background to my field of study and the results obtained during my research program. Chapter 1 gives a very brief introduction to photodynamic therapy including the mechanism of the treatment, the localization of photosensitizer in tumor cells, the pathways leading to tumor death and characteristics of various photosensitizers such as porphyrin-based photosensitizers and non-porphyrin based photosensitizers. Chapter 2 reports a total synthesis of zinc(II) isoporphyrins by cyclization of b-bilene salt using á-keto esters for the macrocyclization carbon. Functionalization of the resulting zinc(II) isoporphyrins was attempted using different strategies …


Microfluidic And Nanofluidic Devices - Mixed Scale Systems For Bioanalytical Applications, Michael David Vincent Jan 2014

Microfluidic And Nanofluidic Devices - Mixed Scale Systems For Bioanalytical Applications, Michael David Vincent

LSU Doctoral Dissertations

Developments in the field of microfluidics and nanofluidics allow an experimenter to employ new analytical techniques. One direction in which the field is moving towards is developing new devices and or instruments on the smallest scale possible. One way in which this can be achieved is by using a combination of top-down and bottom-up technologies. Some of these top-down techniques have been used in other fields such as the use of photolithography to fabricate semiconductors. Photolithography is a top-down method used to create features normally on the micrometer scale, but in order to create nanometer size features another top-down method …


Synthetic Routes To Therapeutic Agents Via Masked Functionalities: From Orthogonal Peptide Crosslink To Photothermal Cancer Prodrug, Chyree Shantel Batton Jan 2014

Synthetic Routes To Therapeutic Agents Via Masked Functionalities: From Orthogonal Peptide Crosslink To Photothermal Cancer Prodrug, Chyree Shantel Batton

LSU Doctoral Dissertations

The theonellamides are a family of compounds distinguished by their crosslinking ô-histidinoalanine (ô-HAL) residue. Part one of this dissertation details the synthesis of an orthogonally protected ô-HAL building block that will be incorporated into a total synthesis of theonellamide C. Selective deprotection of each amine and acid of this orthogonally protected building block is also demonstrated. Various reaction partners for the assembly of ô-histidinoalanine were explored. One approach involved the coupling of N-Fmoc-â-iodoalanine benzyl ester and (Nðim)-blocked histidine nucleophiles including a fused bicyclic urea and a Boc-His(Nð-Pac)-OMe. While the imidazolium salts were identified by mass spectrometry, elimination of the iodide …


Reductive Alkylation Of Proteins Towards Structural And Biological Applications, Kevin Jerome Roberson Jan 2014

Reductive Alkylation Of Proteins Towards Structural And Biological Applications, Kevin Jerome Roberson

LSU Doctoral Dissertations

Nuclear magnetic resonance (NMR) spectroscopy is a proven technique for protein structure and dynamic studies, typically requiring the incorporation of stable magnetic isotopes to improve sensitivity and assign resonances. Degenerate levels of 13C-incorporation have been the biggest obstacle for mass spectrometry-assisted assignment of 13C-dimethylamine resonances in nuclear magnetic resonance spectroscopy (NMR). Reductive 13C-methylation is an alternative labeling method for proteins not amenable to bacterial host overexpression. Because reductive 13C-methylation adds sparse, isotopic labels, traditional methods of assigning the NMR signals are not applicable. The research presented in the first part of this dissertation explores several methods used to break the …


Design, Synthesis, And Exploration Of A Chimeric Antioxidant And New Crosslinkers For Molecular Imprinting, Danielle Songe Meador Jan 2014

Design, Synthesis, And Exploration Of A Chimeric Antioxidant And New Crosslinkers For Molecular Imprinting, Danielle Songe Meador

LSU Doctoral Dissertations

The improvement and utility of crosslinkers are important topics of molecular imprinting. Crosslinker significance is evident when molecularly imprinted polymer (MIP) composition related to performance as separation media is examined. Crosslinkers account for the bulk of MIP formulations made through traditional imprinting (80-90%) and is even greater when the One Monomer Molecularly Imprinted Polymer (OMNiMIP) approach is utilized (100%.) It is not surprising that alteration of the bulk component will result in different separation performances. Crosslinkers studied in this work were designed, synthesized, and evaluated toward improvement in OMNiMIP selectivity. In particular, functionality and number of polymerizable groups, addition of …


Substitution And Disorder Effects In Ternary Intermetallics, Larico Juan Treadwell Jan 2014

Substitution And Disorder Effects In Ternary Intermetallics, Larico Juan Treadwell

LSU Doctoral Dissertations

The focal point of this dissertation is the investigation of substitution and disorder effects in ternary intermetallics. The crystal growth, crystal structure, and physical properties are reported on single crystals of Ln6W4-xAl43-yTx+y (Ln = Gd, Yb; T= Mn, Fe), LnCr2FexAl20-x (Ln = Yb, Gd), Sm1.33Pd3Ga8, and CeCo2-xMxAl8 (M = Mn, Fe, Ni; 0 ≤ x < 1). The reported compounds were grown via the flux growth method with the strategic synthetic parameters described. Correlations between the structural and physical properties in relation to substitution and disorder of Ln6W4-xAl43-yTx+y (Ln = Gd, Yb; T= Mn, Fe), LnCr2FexAl20-x (Ln = Yb, Gd), Sm1.33Pd3Ga8, and CeCo2-xMxAl8 (M = Mn, Fe, Ni; 0 ≤ x < 1) are discussed. The synthesis and characterization of Mn- and Fe- substituted Ln6W4Al43 (Ln = Gd, Yb) are reported. The compounds adopt the Ho6Mo4Al43 structure type with lattice parameters of a ~ 11 Å and c ~ 17.8 Å with structural site preferences for Mn and Fe. The magnetization of Yb6W4Al43 is sensitive to Mn and Fe doping, which is evident by an increase in the field dependent magnetization. Gd6W4Al43, Gd6W4Al42.31(11)Mn0.69(11), and Gd6W4Al41.69(12)Fe1.30(12) order antiferromagnetically in the ab- and c-direction at 15, 14, and 13 K, respectively, with positive Weiss constants, suggesting the presence of ferromagnetic exchange interactions. Anisotropic magnetization data of Gd6W4Al43-yTy (T= Mn, Fe) analogs are discussed. Crystal growth, structure determination, and magnetic properties of LnCr2Al20-xFex (Ln = La, Gd, Yb) adopting the CeCr2Al20 structure type with space group Fd3¯ m, a ~ 14.5 Å, type are reported. Single crystal X-ray diffraction and Mössbauer spectroscopy are employed to fully characterize the crystal structure of LnCr2Al20-xFex (Ln = La, Gd, Yb). LnCr2Al20-xFex (Ln = La, Gd, Yb) are the first pseudo-ternaries adopting the CeCr2Al20 structure type with a transition metal occupying the main group site. The Yb analogues are Pauli paramagnets with the Yb ion adopting an electronic configuration close to Yb2+, while the Gd analogues show paramagnetic behavior with no magnetic order down to 3 K. The synthesis and characterization of Sm1.33Pd3Ga8 is reported. Sm1.33Pd3Ga8 adopts a disordered variant of the Er4Pt9Al24-structure type with lattice parameters of a = 4.353(5) and c = 38.98(4) Å and V = 639.70(12) Å3. The structure of Sm1.33Pd3Ga8 is composed of three distinct building blocks: Pd2Ga4, PdGa2, and Sm0.67Ga. The Sm0.67Ga slab does not magnetically order, which directly affect the structure. Sm1.33Pd3Ga8 is a temperature independent paramagnet. Field dependent magnetization of Sm1.33Pd3Ga8 displays anisotropic behavior. Single crystals of CeCo2-xMxAl8 (M = Mn, Fe, Ni; 0 ≤ x < 1) were grown and crystallize in the CaCo2Al8 structure type with space group Pbam. Single crystal X-ray diffraction data suggest that the Ce 4f-state is valence fluctuating as Fe concentration increases, whereas the Ni-doped analogues do not exhibit valence fluctuating. The results suggest that hole doping leads to an admixture of Ce3+/Ce4+.


Synthesis, Characterization, And Theoretical Studies Of Fluorescent Gumbos And Nanogumbos, Chengfei Lu Jan 2014

Synthesis, Characterization, And Theoretical Studies Of Fluorescent Gumbos And Nanogumbos, Chengfei Lu

LSU Doctoral Dissertations

In this dissertation, novel fluorescent materials, which are referred to as a group of uniform materials based on organic salts (GUMBOS) are synthesized, characterized, and studied for different applications. GUMBOS are solid state organic salts having melting points from 25°C to 250°C. Similar to ionic liquids, GUMBOS are highly tunable and can be designed for specific applications by incorporating multiple-functions into a single ion pair by selection of cation-anion combinations. Chapter 2 is a discussion of the synthesis and characterization of a PEGylated IR786 GUMBOS. These GUMBOS are prepared by a two-step synthesis procedure followed by a facile anion exchange …


Scanning Probe Investigations Of Magnetic Nanoparticles, Protein Binding And The Synthesis Of Rare Earth Oxide Nanoparticles Using Nanoscale Lithography, Lauren Elizabeth Englade-Franklin Jan 2014

Scanning Probe Investigations Of Magnetic Nanoparticles, Protein Binding And The Synthesis Of Rare Earth Oxide Nanoparticles Using Nanoscale Lithography, Lauren Elizabeth Englade-Franklin

LSU Doctoral Dissertations

Approaches to prepare spatially selective surfaces were developed in this dissertation for constructing assemblies of biomolecules and inorganic materials. Nanoscale surface patterns of organic thin films were prepared using particle lithography combined with organosilane chemistry. Biological and inorganic nanomaterials can be patterned with tailorable periodicities, which can be controlled by selecting the diameter of mesospheres used as surface masks. The surface platforms of well-defined nanopatterns are ideal for high resolution investigations using scanning probe microscopy (SPM). Local measurements of surface properties combined with visualization of the steps of chemical reactions at the molecular level were accomplished. Fundamental studies of the …


From Micro- To Nano-Scale: Applications Of Solid-Phase Enzymatic Reactors For Biopolymer Disassembly, Nyote J. Calixte Jan 2014

From Micro- To Nano-Scale: Applications Of Solid-Phase Enzymatic Reactors For Biopolymer Disassembly, Nyote J. Calixte

LSU Doctoral Dissertations

The process of immobilizing enzymes onto solid supports for bioreactions has some compelling advantages compared to their solution-based counterpart including the facile separation of enzyme from products, elimination of enzyme autodigestion, and increased enzyme stability and activity. We report in this work, the immobilization of λ-exonuclease onto poly(methylmethacrylate) (PMMA) micro- and nano-pillars populated within a fluidic devices for the micro and nanoscale on-chip digestion of double-stranded DNA. Enzyme immobilization in both studies was successfully accomplished using 3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS) coupling to carboxylic acid functionalized PMMA micropillars. Our micro-scale results suggest that the reaction efficiency for the catalysis of dsDNA digestion …


The Contribution Of Fly Ash Components To Pcdd/F Formation, Phillip M. Potter Jan 2014

The Contribution Of Fly Ash Components To Pcdd/F Formation, Phillip M. Potter

LSU Doctoral Dissertations

Chlorinated aromatics undergo surface-mediated reactions with metal oxides to form environmentally persistent free radicals (EPFRs) which can further react to produce polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Previous work using laboratory-made fly ash surrogates composed of transition metal oxides deposited on silica powder has confirmed their ability to mimic fly ash in the production of PCDD/Fs. However, little is known about the propensity of alumina and aluminosilicates to form PCDD/Fs. Cooperative catalysis between transition metals in the formation of PCDD/Fs has also seen little research. A fly ash sample containing both alumina and mullite, an aluminosilicate, was tested for PCDD/F formation …


Development Of Visible Light-Promoted Photocatalytic O-Glycosylation, C-H Activation Of Alkanes And Deoxygenation Of N-(Mesyloxy) Amides, Xiaoping Wang Jan 2014

Development Of Visible Light-Promoted Photocatalytic O-Glycosylation, C-H Activation Of Alkanes And Deoxygenation Of N-(Mesyloxy) Amides, Xiaoping Wang

LSU Master's Theses

This thesis is divided into four chapters reporting various aspects of the background of studies and the preliminary results I obtained in three projects. Chapter 1 gives a brief introduction to the concepts of photoredox catalysis, O-glycosylation, C-H functionalization and amidyl radicals. Chapter 2 describes the development of a visible light-promoted O-glycosylation catalyzed by Ru(bpy)3(PF6)2 or diphenyldiselenide under mild conditions. The glycosylation of primary and secondary alcohols with selenoglycosides was demonstrated with good yields, and disaccharides were constructed by coupling of the selenoglycosides in acetonitrile or dichloromethane with a glucosyl acceptor in moderate yields. The reactions catalyzed by Ru(bpy)3(PF6)2 were …


Particle Formation In Ambient Mass Spectrometry, Thabiso Musapelo Jan 2014

Particle Formation In Ambient Mass Spectrometry, Thabiso Musapelo

LSU Doctoral Dissertations

A particle sizing system was developed that couples a light scattering particle sizer with a differential mobility analyzer for particle detection and elucidation with the capability for measuring particle sizes in the range of 10 nm to 20 μm. The particle sizing system was used to investigate particle formation that is associated with several methods of atmospheric pressure ion formation used in mass spectrometry: atmospheric pressure matrix-assisted laser desorption ionization (MALDI) and inlet ionization. The methods for particle formation were 1) ultraviolet (UV) laser ablation, 2) infrared (IR) laser ablation, and 3) shock-generated particle formation. Particles formed by UV laser …