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Articles 421 - 450 of 619
Full-Text Articles in Chemistry
Utilization Of Aptamers As Affinity Probes In Polymeric Microdevices For Disease Management And The Production Of A Recombinant Membrane Protein, Anne Obubuafo
LSU Doctoral Dissertations
Aptamers have emerged as potential affinity agents that rival or complement antibodies in developing diagnostic assays for disease detection. We have demonstrated the use of PMMA microfluidic devices for conducting rapid affinity microchip CGE of a target protein using aptamers as the affinity probes with an electrophoresis development time of <2 min. Migration times were reproducible for thrombin complexes and free aptamers in CGE buffer with device-to-device RSD variations below 10%. By removing salts from plasma and adding an unlabeled random sequence oligonucleotide to the plasma, thrombin was detected in plasma. This method can be easily adapted to high-throughput parallel screening of plasma samples in multi-channel polymeric microdevices. The expression of rEpCAM in bacteria and mammalian cells was investigated with results showing successful expression in the mammalian systems, while protein expression in the bacteria was inhibited. Higher and prolonged expression levels were obtained in Cos 7 cells as compared to BHK and Hep2 cells due to episomal expression in Cos 7 cells. By combining a one-step IMAC procedure with electrophoresis and electro elution a more selective approach to obtaining electrophoretically pure rEpCAM was achieved. We developed dual-aptamer sandwich assays for thrombin and PDGF-BB targets on PMMA substrate using UV modification with a one-step EDC/NHS coupling reaction. Results indicate that the use of high EDC concentrations lead to faster immobilization and increased coverage density with a shorter sandwich assay development time. The assays were sensitive for both proteins and showed linearity in fluorescence response to changing protein concentration. Single molecule detection methods provide high sensitivity techniques in which aptamers can find use. We have demonstrated the use of two aptamers in a FRET-based assay for the detection of low levels of thrombin. Sensitivity and reliability of the aptamer smFRET assay depends on complex formation and stability. Due to the dissociation constants of the aptamers, single molecule events detected were below the calculated value for a 6 pM concentration of thrombin. Future work will involve adjusting the single molecule system by the use of pinholes to enable analysis of higher sample concentrations.
Novel Devices And Protocols Enabling Isolation And Enumeration Of Low Abundant Biological Cells From Complex Matrices, Andre Antonio Adams
Novel Devices And Protocols Enabling Isolation And Enumeration Of Low Abundant Biological Cells From Complex Matrices, Andre Antonio Adams
LSU Doctoral Dissertations
The dimensions of microfluidic devices closely parallel those of biological cells; thusly, they are excellent platforms for the speciation, transport, manipulation, and analysis of cells. Electrokinetic transport of Escherichia coli and Saccharomyces cerevisiae was evaluated in microfluidic devices fabricated in pristine and UV-modified poly(methylmethacrylate) and polycarbonate. The magnitude and direction of transport of the cells was dictated by the buffer composition, conduit surface chemistry, and intrinsic cellular electrical properties. Baker’s yeast in all devices migrated toward the cathode, because of their smaller electrophoretic mobility compared to the electroosmotic flow of the polymer. E. coli cells suspended in 20 mM PBS …
Solid-Phase Synthesis Of Asymmetrically Substituted Phthalocyanines, Sultan Sibel Erdem
Solid-Phase Synthesis Of Asymmetrically Substituted Phthalocyanines, Sultan Sibel Erdem
LSU Doctoral Dissertations
Phthalocyanines (Pcs) are excellent candidates for use as fluorophores for near-infrared (near-IR) fluorescent tagging of biomolecules and as photodynamic therapy (PDT) agents. Synthesis of Pcs with asymmetrical substitution on the periphery is often difficult due to the problems during the purification of the Pc mixtures obtained. The objective of this project is to design and synthesize chemically robust near-IR fluorophores for bioanalytical applications and to develop new synthetic methods for rapid synthesis of the target compounds. A novel synthetic route was developed utilizing a hydrophilic, polyethylene glycol-based (PEG) support with different types of linkers. The Pcs were functionalized with either …
Synthesis Of Disubstituted Amino Acids And Peptide Inhibitors Of Amyloid Beta Aggregation, Gregory Todd Mccandless
Synthesis Of Disubstituted Amino Acids And Peptide Inhibitors Of Amyloid Beta Aggregation, Gregory Todd Mccandless
LSU Master's Theses
The aggregation process of amyloid beta from monomeric peptide to oligomers and fibrils is believed to be connected with the neurological disorder Alzheimer’s disease. The focus of this research is the synthesis of alpha, alpha-disubstituted amino acids and peptide inhibitors of amyloid beta aggregation. The inhibitors are designed to interrupt (or alter) this process by binding to amyloid beta’s central hydrophobic core region (residues 17-20, Leucine-Valine- Phenylalanine-Phenylalanine). Target specificity is achieved via self recognition by basing the inhibitors on the sequence in this region. The inclusion of disubstituted amino acids in the sequence of the inhibitors will provide a blocking …
Designing Surface Chemistries For In Situ Afm Investigations Of Biomolecular Reactions With Proteins At The Nanoscale, Johnpeter Ndiangui Ngunjiri
Designing Surface Chemistries For In Situ Afm Investigations Of Biomolecular Reactions With Proteins At The Nanoscale, Johnpeter Ndiangui Ngunjiri
LSU Doctoral Dissertations
In situ atomic force microscopy (AFM) characterizations and lithography can be applied to investigate the orientation, reactivity and stability of protein molecules adsorbed on nanostructures of self-assembled monolayers at near-physiological conditions. Automated nanografting was used to fabricate regular arrays of nanopatterns of ù-functionalized n-alkanethiols with designated terminal chemistries. After writing nanopatterns, protein binding occurs selectively on carboxylate-terminated nanopatterns via covalent bonds that are formed using N-ethyl-N'(dimethylaminoporpyl)-carbodiimide and N-hydroxysuccinimide activation. The amine groups of lysine residues of proteins bond covalently to nanopatterns of carboxylate-terminated alkanethiol self-assembled monolayers, to form a robust surface attachment for sustained contact-mode AFM imaging during biochemical reactions. …
Bioanalytical Methods For Studies Of Homocysteine And Novel Cardiovascular Disease Indicators, Arther T. Gates
Bioanalytical Methods For Studies Of Homocysteine And Novel Cardiovascular Disease Indicators, Arther T. Gates
LSU Doctoral Dissertations
This dissertation explores the development of analytical methods for studies of CVD biomarkers and related biomolecular indicators. Initially, spectroscopic studies were conducted to investigate the chemical reactivity of homocysteine (Hcy), an independent CVD risk factor and serological biomarker. Consequently, we proposed an alternate theory for in vivo Hcy clearance based on spontaneous pyridoxal tetrahydrothiazine (PT) formation from Hcy and pyridoxal. The validity of PT-assisted Hcy clearance was further evaluated by use of capillary electrophoretic methods, which allowed rapid monitoring of protein oligomerization in PT-protein reaction mixtures. The results of these studies suggest that PT formation is a plausible mechanism for …
Synthesis And Surface Characterization Of Silica-Polypeptide Composite Particles, Erick Isael Soto-Cantu
Synthesis And Surface Characterization Of Silica-Polypeptide Composite Particles, Erick Isael Soto-Cantu
LSU Doctoral Dissertations
The synthesis and sequential surface characterization of silica-polypeptide composite particles is described. Nearly monodisperse colloidal silica cores were obtained by the alkaline hydrolysis of tetraethyl orthosilicate (TEOS). The hydrodynamic radius can be easily controlled in the range of ƒî 20-140 nm by the water/TEOS ratio in the starting reaction mixture. The surface of the synthesized silica cores was further passivated/functionalized (P/F) by a mixture of (3-aminopropyl) trimethoxysilane (APS) and methyl-trimethoxysilane (MTMS). The amino groups were quantified using UV-Vis spectrometry after reaction with ninhydrin. The use of zeta potential measurements of the P/F silica particles at low pH is presented as …
Exploration Of New Ternary Gallides And Investigation Of Their Structure-Property Relationships, Jung Young Cho
Exploration Of New Ternary Gallides And Investigation Of Their Structure-Property Relationships, Jung Young Cho
LSU Doctoral Dissertations
This dissertation focuses on the investigation of new ternary intermetallic gallides, which may exhibit exotic physical properties such as heavy-fermion behavior, large magnetoresistance, and even superconductivity. In particular, the Ln-Cu-Ga (Ln = lanthanides) system has been systematically investigated by changing a reaction ratio and/or using a different temperature profile to optimize desired phases. Single crystals of Ln2MGa12 (Ln = La, Ce; M = Ni, Cu) have been synthesized using Ga flux and compared to their Pd analogues. Interestingly, Ce2MGa12 (M = Ni, Cu) show enhanced Sommerfeld coefficient of ¡Ö 191 mJmol-1K-2 and ¡Ö 69 mJmol-1K-2 for Ni and Cu compounds, …
The Synthesis Of Water Soluble N-Acyl Chitosan Derivatives For Characterization As Antibacterial Agents, Lakia Monique Champagne
The Synthesis Of Water Soluble N-Acyl Chitosan Derivatives For Characterization As Antibacterial Agents, Lakia Monique Champagne
LSU Doctoral Dissertations
Currently, natural polysaccharides are being utilized increasingly in the markets because they exhibit biodegradability, biocompatibility, versatility, and are found abundant in nature. The diversity of natural polysaccharides provides the chemist with a broad spectrum of raw materials that can be used in many biological applications. Chitosan is a natural polysaccharide that possesses excellent biological properties. It has been recognized for its antibacterial activity, in that it is destructive towards the bacterium Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The antibacterial property of chitosan can be enhanced by changing the hydrophobic/hydrophilic nature of the polysaccharide backbone. This research entails …
Revolutionizing Genomic Analyses: Mutation Analyses Using Novel Enzyme-Based Assays With Laser-Induced Fluorescence And Polymeric Microfluidic Devices As Electrophoretic Platforms, Rondedrick Deshaun Sinville
Revolutionizing Genomic Analyses: Mutation Analyses Using Novel Enzyme-Based Assays With Laser-Induced Fluorescence And Polymeric Microfluidic Devices As Electrophoretic Platforms, Rondedrick Deshaun Sinville
LSU Doctoral Dissertations
Polymer-based microelectrophoresis was investigated to analyze known (mutation detection) and unknown (mutation scanning) low-abundant mutations in genomic DNA with high diagnostic value for colorectal cancers. For our mutation detection assays, point mutations in the K-ras oncogene were identified using the ligase detection reaction (LDR). For the mutation scanning assay, which searches for sporadic mutations, an EndoV-LDR assay was utilized with mutations in the p53 tumor suppressor gene used as a model. A poly(methylmethacrylate), PMMA, microchip filled with a 4% linear polyacrylamide (LPA) gel was used to electrophoretically sort products formed from LDRs, which produced oligonucleotides <65 bp in length. Using microchip electrophoresis with the LPA, a 44 bp ligation product was resolved from a 100-fold molar excess of unligated primers (25 bp) in approximately 120 s, which was ~17 times faster than conventional capillary gel electrophoresis. In order to simplify the electrophoretic process and further reduce development time, the LDR products were sorted in the absence of the sieving gel using free solution conjugate electrophoresis (FSCE). FSCE incorporated polyamide “drag-tags” onto LDR primers, which provided DNA fragment mobilities in free solution that were dependent upon their size. LDR/drag-tagged (LDR-dt) products could be formed in a multiplexed format for mutant-to-wild-type ratios as low as 1 to 100 with single base resolution. Separations were conducted using capillary array electrophoresis (CAE) and PMMA microchips filled with only a TRIS buffer. Analysis times for the LDR-dt products were less than 11 min using CAE and ~85 s for PMMA microchips with high reproducible migration times within and between microchips. PMMA-based microchips were also evaluated for the identification of sporadic mutations using an endonuclease V – LDR (Endo V/LDR) technique. Endo V cleaves heteroduplexed DNA one base 3’ of single-base mismatched sites as well as nicking DNA at some matched sites as LDR reseals miscleaved sites to reduce false positive signals. Results suggested that Endo V/LDR products from p53 mutations could be successfully separated and detected using a PMMA microfluidic chip filled with a sparsely cross-linked replaceable polyacrylamide gel in less than 6 min, which was approximately 10-fold shorter compared to CAE.
Retro Models Of The Cisplatin-Dna Cross-Link With Carrier Ligands Having Sp2 N-Donor Triazine Rings, Vidhi Maheshwari
Retro Models Of The Cisplatin-Dna Cross-Link With Carrier Ligands Having Sp2 N-Donor Triazine Rings, Vidhi Maheshwari
LSU Doctoral Dissertations
Rapid rotation of guanine base derivatives about Pt–N7 bonds results in fluxional behavior of models of the key DNA intrastrand G–G cross-link leading to anticancer activity of Pt(II) drugs (G = deoxyguanosine). This behavior impedes the characterization of LPtG2 models (L = one bidentate or two cis-unidentate carrier ligands; G = guanine derivative). The objective of this study is to understand the types of conformers formed as L is systematically varied. This work, relevant to Pt(II) anticancer drugs, has evolved from published studies with sp3 N-ligands (e.g., 2,2'-bipiperidine), to C2 symmetrical or unsymmetrical sp2 N-ligands having pyridine and/or triazine rings. …
Development Of New Stimuli-Responsive Vesicles Using A Novel Surfactant, Yuming Yang
Development Of New Stimuli-Responsive Vesicles Using A Novel Surfactant, Yuming Yang
LSU Doctoral Dissertations
Many amphiphilic molecules (surfactants) possess the ability to aggregate in aqueous solution to form thermodynamically stable aggregates that have potential for use as molecule containers and delivery systems in analytical or pharmaceutical applications. However, it is difficult to release the encapsulated molecules from these aggregates under a controllable manner, and this problem has dramatically limited the application of these aggregated systems. This study addresses this problem through fundamental structure modification by development of a novel redox stimuli-responsive amphiphile capable of forming vesicle aggregates. Aggregate structure can be adjusted through redox stimulation. The release of agents from the core of the …
Incorporation Of Cα,Α-Disubstituted Amino Acids Into Model Peptide Systems: Conformational Analysis And Possible Applications As Therapeutic Agents, Marcus A. Etienne
Incorporation Of Cα,Α-Disubstituted Amino Acids Into Model Peptide Systems: Conformational Analysis And Possible Applications As Therapeutic Agents, Marcus A. Etienne
LSU Doctoral Dissertations
A diverse set of human diseases is associated with the misfolding of proteins into insoluble fibrillar structures that have predominantly β-sheet secondary structure. Thus it is imperative to elucidate the structural elements that contribute to β-sheet formation and stability. Peptides that autonomously form β-sheets are ideal models to study principles of protein folding and design. Gellman and coworkers first introduced an automonously folded β-hairpin (H-Arg-Tyr-Val-Glu-Val-Yyy-Xxx-Orn-Lys-Ile-Leu-Gln-NH2) that remained monomeric up to ~1 mM. Circular dichroism (CD) and nuclear magnetic resonance (NMR) analyses revealed that incorporation of non-stereogenic Aib-Xxx dipeptidyl sequences into i+1 and i+2 positions of a model peptide nucleates a …
Chemical Analysis Of Polymer Blends Via Synchrotron X-Ray Tomography, Heath Alan Barnett
Chemical Analysis Of Polymer Blends Via Synchrotron X-Ray Tomography, Heath Alan Barnett
LSU Doctoral Dissertations
Material properties of industrial polymer blends are of great importance. X-ray tomography has been used to obtain spatial chemical information about various polymer blends. The spatial images are acquired with synchrotron X-ray tomography because of its rapidity, good spatial resolution, large field-of-view, and elemental sensitivity. The spatial absorption data acquired from X-ray tomography experiments is converted to spatial chemical information via a linear least squares fit of multi-spectral X-ray absorption data. A fiberglass-reinforced polymer blend with a new-generation flame retardant is studied with multi-energy synchrotron X-ray tomography to assess the blend homogeneity. Relative to other composite materials, this sample is …
Concentration Of Phosphorylated Proteins Using Modified Pmma Microanalytical Devices, Jowell Guerra Bolivar
Concentration Of Phosphorylated Proteins Using Modified Pmma Microanalytical Devices, Jowell Guerra Bolivar
LSU Doctoral Dissertations
This work describes the application of PMMA-based microanalytical devices for the affinity-type preconcentration of posttranslational modified proteins (PTMs). The choice of poly(methyl methacrylate), PMMA, is based on its biocompatibility, its functional methyl ester group for potential modification, and its extensive applications to create biological microelectromechanical systems (BioMEMS). Developing methodologies for preconcentration of PTMs is important for cancer diagnosis due to PTMs’ influence in the regulatory mechanism underlying the early stage of apoptosis or regulated cell death. Towards this goal, nitroavidin which can reversibly binds to biotin (and biotinylated proteins), was prepared using reported procedure and was characterized using several techniques …
Syntheses Of Trimethylamine- And Phosphonate- Substituted Carboranylporphyrins For Application In Boron Neutron Cancer Therapy, Michael William Easson
Syntheses Of Trimethylamine- And Phosphonate- Substituted Carboranylporphyrins For Application In Boron Neutron Cancer Therapy, Michael William Easson
LSU Doctoral Dissertations
Chapter 1 contains an introduction to porphyrins and carboranylporphyrins, including their physical properties, history, methods of synthesis, medicinal applications, and an overview of recently published compounds. Chapter 2 contains the total synthesis of a series of trimethylamine- and phosphonate-substituted carboranylporphyrins for application in boron neutron capture therapy (BNCT), including characterization by proton nuclear magnetic resonance spectroscopy, matrix-assisted time-of-flight mass spectroscopy, high resolution mass spectroscopy, UV-Vis spectrophotometry, X-ray crystallography, and melting point apparatus. Chapter 3 contains synthetic methods which were investigated as alternate routes to porphyrin synthesis and functionalization. Chapter 4 presents the in vitro biological evaluation of trimethylamine- and phosphonate-substituted …
Syntheses And Evaluation Of Phthalocyanine Derivatives For Applications In Photodynamic And Boron Neutron Capture Therapies For Cancer, Hairong Li
LSU Doctoral Dissertations
Chapter I introduced the background of phthalocyanines including its physical properties and various synthetic methods of free-base and metallo-phthalocyanines. The background of PDT and BNCT was introduced and the objective of ideal sensitizers was described. Chapter II described the synthesis and characterization of a series of pyridiloxy-substituted zinc phthalocyanines with different length of alkyl groups. Pyridiloxy-substituted silica phthalocyanines bearing different associated axial ligands, were alkylated with methyl or PEG chains. Biological study was performed on these cationic pyridiloxy-substituted zinc phthalocyanines. Chapter III introduced the synthesis and photophysical properties of A3B-type zinc phthalocyanines conjugated with one or two cobalta-carborane cages. They …
Novel Synthesis Of Xanthene And Benzoxanthene Dyes, Corin Michelle Schowalter
Novel Synthesis Of Xanthene And Benzoxanthene Dyes, Corin Michelle Schowalter
Honors Capstones
No abstract provided.
Structural Manipulation Of Pyrrole-Terminated Dendrimers To Create A More Efficient Encapsulation/Release System, Henry Wiggins
Structural Manipulation Of Pyrrole-Terminated Dendrimers To Create A More Efficient Encapsulation/Release System, Henry Wiggins
LSU Doctoral Dissertations
This work demonstrates the ability to manipulate the structure of pyrrole-terminated dendrimers by modifying solution conditions which directly affects their encapsulation properties. Investigations were conducted using FTIR and 2D NMR to determine the location of end groups. NMR relaxation studies were conducted at various temperatures and different solution pH to gain an understanding of the relative mobility and rigidity of different areas of the dendrimer. It was found that that the release properties were affected by the solution pH and the presence of salt. Further the effectiveness of retaining molecular guests by oligo-pyrrole terminated dendrimers with a range of oligomer …
Investigation Of Phospholipid Tubule Morphology For Use In Drug Delivery, Colleen Colson Garrett
Investigation Of Phospholipid Tubule Morphology For Use In Drug Delivery, Colleen Colson Garrett
LSU Doctoral Dissertations
Spherical vesicles consisting of phosphatidylcholines in which diacetylene groups have been inserted in the hydrocarbon tail centers give rise to hollow cylindrical tubes, known as “tubules”. The study of tubules has become an area of intense interest in recent years due to their unusual morphology, which raises several profound theoretical issues and suggests their use in a variety of applications. Tubule hollowness suggests medical and industrial encapsulations as well as filtration and purification applications. These potential uses, e.g., for drug and gene delivery, requires optimization of their morphology for the application. Tubules have many technologically desirable properties, such as a …
Elementary Reactions Involved In Pollutant-Forming Mechanisms, Cheri Ann Mcferrin
Elementary Reactions Involved In Pollutant-Forming Mechanisms, Cheri Ann Mcferrin
LSU Doctoral Dissertations
The reactions of the hydroxyl radical (OH) with molecular chlorine (Reaction 1), methane (Reaction 2), and propane (Reaction 3) have been studied experimentally using a pulsed laser photolysis/pulsed-laser-induced fluorescence technique over wide ranges of temperatures (297-826, 298-1009, and 296-908 K, respectively) and at pressures between 6.68 and 24.15 kPascals. The rate coefficients for these reactions exhibit no dependence on pressure and exhibit positive temperature dependences that can be represented with modified three-parameter Arrhenius expressions within their corresponding temperature ranges: k1 = 3.59 x 10-16T1.35exp(-745K/T)cm3molecule-1sec-1, k2 = 3.82 x 10-19T2.38 exp(-1136K/T)cm3molecule-1sec-1, and k3 = 6.64 x 10-16T1.46 exp(-271K/T)cm3molecule-1sec-1. For the OH …
Properties Of Silica-Polypeptide Composite Particles, Jianhong Qiu
Properties Of Silica-Polypeptide Composite Particles, Jianhong Qiu
LSU Doctoral Dissertations
Studies of grafting polymer on surfaces with chemical bonds started in the 1970’s, but few projects have focused on grafting polypeptide on spherical particles. In this research, polypeptides poly(å-carbobenzyloxy-L-lysine) (PCBL) or poly(ã-benzyl-L-glutamate) (PBLG) were grafted on silica sphere surfaces by using the “grafting from” method. The polypeptide-grafted silica spheres are called SiPCPs. The growth of polypeptide chains as a function of monomer amount and reaction time was explored. The properties of a mixture of PBLG rod-like polymer and PBLG SiPCPs were investigated. At high concentrations of these two components, the phase behavior was studied. At low concentrations of PBLG, the …
Wet And Dry Aging Of Polymer-Asphalt Blends: Chemistry And Performance, Ionela Chiparus Glover
Wet And Dry Aging Of Polymer-Asphalt Blends: Chemistry And Performance, Ionela Chiparus Glover
LSU Doctoral Dissertations
A PG 76-22 Polymer Modified Asphalt Cement composition was subjected in the laboratory to accelerated aging using both a standard Thin Film Oven Test and a Pressure Aging Vessel. Conditions simulating wet atmospheres (PAV in saturated water vapors) as well as very long service terms (multiple dry and wet PAV operations) were studied. A Rotating Cylinder Aging Test has been employed as an alternate asphalt aging technique using the same PMAC composition in order to observe the initial phases of the oxidative aging process. The data provided by this technique was correlated with the actual aging in the field of …
Stereochemical And Regiochemical Trends In The Selective Spectrophotometric Detection Of Biological Molecules, Shan Jiang
LSU Doctoral Dissertations
Useful mechanistic studies to date concerning sugar detection by arylboronic acid chemosensors have mainly involved the elucidation of equilibrium constants and the role of boron-nitrogen interactions in signal transduction. However, several discreet sugarboronate complexes exist in solution. This is due to the complex equilibria between isomeric species of even the simplest monosaccharides. Relatively few reports have been devoted to a systematic study of the structures of each of the corresponding individual sugar-boronate complexes. We have investigated some of the precise regio- and stereochemical features of the various equilibrating sugar isomers that induce selective signal transduction. As a result of this …
Synthesis And Evaluation Of Derivatives And Analogs Of Xanthene Dyes, Xiangyang Xu
Synthesis And Evaluation Of Derivatives And Analogs Of Xanthene Dyes, Xiangyang Xu
LSU Doctoral Dissertations
Xanthene dyes are one of the oldest synthetic dyes. Fluorescein was first synthesized by von Baeyer in 1871. Since its discovery, it has been extensively studied. Fluorescein can exist as four different ionic forms (cationic form, neutral form, monoanionic form and dianionic form). Under physiological conditions (pH 7.4), fluorescein mainly exists as the dianionic form which grants it large quantum yield and excellent solubility in water. This renders fluorescein and its derivatives useful for studies in biological media. Cysteine (Cys) and homocysteine (Hcy) are of the few amino acids which contain sulfur and both of them are believed to be …
Development Of Fluorescent Chemosensors Based On Energy Transfer In End-Capped Pi-Conjugated Systems, Huating Zhang
Development Of Fluorescent Chemosensors Based On Energy Transfer In End-Capped Pi-Conjugated Systems, Huating Zhang
LSU Master's Theses
A novel sensory platform based on conjugated polymer was developed, that consists of a monodispersed oligo(phenylene ethynylene) backbone, end-capped with a terminal alkene for further attachment to a solid surface at one terminus, and an anthracene based receptor group at the other terminus. Energy transfer from backbone to end-cap was observed by absorption spectroscopy and fluorescence spectroscopy. Other ongoing projects described herein include the synthesis of longer-chain analogues of the above platform, the synthesis of silica microspheres based conjugated polymer sensory platform and the synthesis of long wavelength (NIR) dye for in vivo amyloid screening studies.
The Use Of A Chiral Fluorescent Resorcinarene For The Enantiomeric Recognition Of Amino Acids, Gerald I. Richard
The Use Of A Chiral Fluorescent Resorcinarene For The Enantiomeric Recognition Of Amino Acids, Gerald I. Richard
LSU Master's Theses
The spectroscopic properties of a chiral boronic acid based resorcinarene macrocycle employed for chiral analysis were investigated. Specifically, the emission and excitation characteristics of tetraarylboronate resorcinarene macrocycle (TBRM) and its quantum yield were evaluated. The chiral selector TBRM was investigated as a chiral reagent for the enantiomeric discrimination of amino acids using steady-state fluorescence spectroscopy. Chiral recognition of amino acids in the presence of the macrocycle was based on diastereomeric complexes. Results demonstrated that TBRM had better chiral discrimination ability for lysine as compared to the other amino acids. Partial-least-squares regression modeling (PLS-1) of spectral data for macrocycle-lysine host-guest complexes …
Multifunctional Ligands For Supramolecular Chemistry, James Kakoullis
Multifunctional Ligands For Supramolecular Chemistry, James Kakoullis
LSU Master's Theses
Metal-organic frameworks (MOFs) are the primary focus of the Maverick research group, almost exclusively with the acac moeity. Before such MOFs can be attempted, multifunctional ligands of the appropriate geometry for the desired MOFs first must be synthesized. In this thesis, the synthesis and characterization of two new β-diketone ligands, specifically, Re(CO)3Cl(PyacH)2, 2.2, Pphac3H3, 1.23, and its oxide 3.6, are described. Also in this thesis, attempts to synthesize other new MOFs will be discussed. The MOF for which Re(CO)3Cl(PyacH)2, 2.2 was designed was Re(CO)3ClCu(pyac)2] …
The Spectral And Photophysical Characterization Of Water Solubilizing Metal Phthalocyanines For Highly Sensitive Detection In Biological Studies, Vera Tamisha Verdree
The Spectral And Photophysical Characterization Of Water Solubilizing Metal Phthalocyanines For Highly Sensitive Detection In Biological Studies, Vera Tamisha Verdree
LSU Doctoral Dissertations
Efforts to improve the technology for DNA analyses stimulated the work presented here to develop a series of fluorescent probes that would aid in the increased multiplexing capabilities allowing the ability to detect multiple targets in a single measurement. Typically, spectral discrimination has been used to identify each DNA fragment in sequencing or diagnostic applications by means of unique emission properties from several labeling dyes. This has been accomplished with labels that fluoresce in the visible region. The limitations with these dyes is the broad emission profile making discrimination difficult, high intrinsic biological fluorescence and structural differences of the dyes …
Fabrication Of Dna Microarrays On Poly (Methylmethacrylate) Substrates For Biomolecular Reporting, Catherine N. Situma
Fabrication Of Dna Microarrays On Poly (Methylmethacrylate) Substrates For Biomolecular Reporting, Catherine N. Situma
LSU Doctoral Dissertations
DNA microarrays require the use of substrates with well-established surface modification / probe attachment chemistries. Glass/quartz have been widely adopted as typical support materials since their surface modification chemistries which involve the use of siloxane –based chemistries have been widely studied however; these chemistry is susceptible to hydrolytic cleavage especially at high or low pH values. Recently, polymers have been sought as alternative microarray support materials but their surface modification strategies are not well characterized compared to glass. This report will entail surface photo-modification of PMMA polymer substrates by UV irradiation which produces functional scaffolds of carboxylic groups that allow …