Chemistry Commons^™

Investigating Color Additive Molecules For Pharmaceutical And Cosmetic Applications: A Comparison Of Theoretical And Experimental Uv-Visible Absorbance Spectra In Tunable Solvents, Jacqueline Casey Mohen

Theses and Dissertations

Color additive molecules have widespread applications ranging from ingestible foods and pharmaceutics to non-ingestible cosmetics and other naturally or synthetically developed consumer products available worldwide. Certification for approved use of color additives varies globally; therefore, a feasible method to analyze existing color additives or to design novel color additive molecules with enhanced or otherwise desired physicochemical properties (such as hue) is in high demand for universal adoption. The studies herein provide sufficient proof that density functional theory and time-dependent density functional theory serve as effective predictive modeling techniques for generating theoretical maximum absorbance spectral peak responsivity for a single color …

Length And Charge Of Water-Soluble Peptoids Impact Binding To Phospholipid Membranes, Madeleine R. Landry, Jacenda L. Rangel, Vivian P. Dao, Morgan A. Mackenzie, Fabiola L. Gutierrez, Kalli M. Dowell, Anna L. Calkins, Amelia A. Fuller, Grace Y. Stokes

Chemistry and Biochemistry

In this study, we provide a quantitative description of the adsorption of water-soluble N-substituted glycine oligomers (peptoids) to supported lipid bilayers that mimic mammalian plasma membranes. We prepared a small array of systematically varied peptoid sequences ranging in length from 3 to 15 residues. Using the nonlinear optical method second harmonic generation (SHG), we directly monitored adsorption of aqueous solutions of 3- and 15-residue peptoids to phospholipid membranes of varying physical phase, cholesterol content, and head group charge in physiologically relevant pH buffer conditions without the use of extrinsic labels. Equilibrium binding constants and relative surface coverages of adsorbed peptoids …

Chemosensors Based On Higher Energy Gap Control Of Fluorescence In Conjugated Polymers, Chun-Han Wang

LSU Doctoral Dissertations

Conjugated polymers (CPs) have been widely investigated for their remarkably high sensitivity towards various chemical detection applications. CPs can exhibit effective transduction of certain analyte binding events through changes in fluorescence. These changes include amplified fluorescence quenching ("turn-offmechanism") or an appearance of a fluorescent emission ("turn-onmechanism"). Whereas turn-offsensors can be readily designed and are widely used, amplifying turn-onsensors, from a practical standpoint, are more convenient to use but are more challenging to design.

This dissertation primarily focuses on the development and study of conjugated polymer based amplifying turn-onfluorescence chemosensors utilizing the novel “higher …

Consumption Of Black Raspberries Altered The Composition Of The Fecal Microbiome In Mice Fed A Western Type Diet (Or04-01-19), Abby D. Benninghoff, Sumira Phatak, Korry Hintze

Chemistry and Biochemistry Faculty Publications

Dietary strategies to reduce colonic inflammation and promote gut homeostasis may markedly reduce the risk of colitis-associated colorectal cancer. Previously, we showed that dietary supplementation with black raspberries significantly suppressed colitis and colon tumorigenesis promoted by the consumption a Western type diet in mice. In this study, our goal was to assess the impact of consumption of the TWD with and without black raspberry supplementation on the composition of the fecal microbiome over the course of disease development.

Dietary Intervention With Black Raspberries To Reduce Colitis Symptoms In Mice Fed Either Standard Ain93g Diet Or The Total Western Diet (P05-021-19), Daphne Michelle Rodriguez Jimenez, Michaela Brubaker, Elizabeth Park, Canyon Neal, Korry Hintze, Abby D. Benninghoff

Chemistry and Biochemistry Faculty Publications

Approximately 1.4 million people suffer from inflammatory bowel disease, which is a major risk factor for developing colitis associated colorectal cancer (CAC). Dietary interventions with the goal to reduce colon inflammation and encourage gut microbiome homeostasis may be a strategy to reduce the risk of CAC. The antioxidants and anti-inflammatory compounds present in black raspberries (BRB) have demonstrated protective effects in the colon epithelium and may alter the composition of the gut microbiome. Previously, we showed that dietary supplementation with black raspberries significantly suppressed colitis and colon tumorigenesis promoted by the consumption of a Western type diet in mice. The …

Useful And Harmful Propeties Of Natural And Synthetic Food Additive, B. Sattorova, I. Asqarov,, A. Joraev,, K. Kirgizov.

Scientific journal of the Fergana State University

The article discusses the useful and harmful properties of natural and synthetic food additives.

Obtaining Of Adsorbents From Fruit Seeds And Studying Their Physicochemical Properties, G’ Ochilov, G. Tursunova, R, Qarabaeva,, A Ibrohimov

Scientific journal of the Fergana State University

The physicochemical properties of adsorbents obtained by thermal processing of stone fruit wastes were investigated. The possibility of their use for the purification of waste water from heavy metal ions in experiments with simulated waste water containing copper ions has been studied.

Useful And Harmful Propeties Of Natural And Synthetic Food Additive, B. Sattorova, I. Asqarov,, A. Joraev,, K. Kirgizov.

Scientific journal of the Fergana State University

The article discusses the useful and harmful properties of natural and synthetic food additives.

Obtaining Of Adsorbents From Fruit Seeds And Studying Their Physicochemical Properties, G’ Ochilov, G. Tursunova, R, Qarabaeva,, A Ibrohimov

Scientific journal of the Fergana State University

The physicochemical properties of adsorbents obtained by thermal processing of stone fruit wastes were investigated. The possibility of their use for the purification of waste water from heavy metal ions in experiments with simulated waste water containing copper ions has been studied.

Integration Of Random Forest Classifiers And Deep Convolutional Neural Networks For Classification And Biomolecular Modeling Of Cancer Driver Mutations, Steve Agajanian, Odeyemi Oluyemi, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

Development of machine learning solutions for prediction of functional and clinical significance of cancer driver genes and mutations are paramount in modern biomedical research and have gained a significant momentum in a recent decade. In this work, we integrate different machine learning approaches, including tree based methods, random forest and gradient boosted tree (GBT) classifiers along with deep convolutional neural networks (CNN) for prediction of cancer driver mutations in the genomic datasets. The feasibility of CNN in using raw nucleotide sequences for classification of cancer driver mutations was initially explored by employing label encoding, one hot encoding, and embedding to …

The (Relative) Insignificance Of G Revisited To Include Nanoparticles, Sungmin Youn, Desmond F. Lawler

All Engineering Faculty Research

The collision efficiency functions, α(i,j), of two colliding particles for the three operative transport mechanisms in flocculation (Brownian motion [Br], fluid shear [Sh], and differential sedimentation [DS]) were numerically calculated over a broad size range (including nanoparticles). All computations include the hydrodynamic force and van der Waals (vdW) attraction, while the effects of electrical double‐layer repulsive forces were investigated by their exclusion or inclusion. Flocculation of nanoparticles should be extremely rapid if they are uncharged but will be dramatically reduced when substantially charged. For small neutral particles, α(i,j) values could …

A Field Procedure To Screen Soil For Hazardous Lead, Franziska C. Landers, Anna Paltseva, Jennifer M. Sobolewski, Zhongqi Cheng, Tyler K. Ellis, Brian J. Mailloux, Alexander Van Geen

Publications and Research

Soils retain lead contamination from possible sources such as mining, smelting, battery recycling, waste incineration, leaded gasoline, and crumbling paint. Such contamination is often concentrated in toxic hot spots that need to be identified locally. To address this need, a simple field procedure was designed to screen soil for hazardous Pb for use by the general public. The procedure is a modification of the in vitro soil Pb extraction described by Drexler and Brattin (Hum. Ecol. Risk Assess. 2007, 13, 383) and EPA Method 1340, and uses a 0.4 M glycine solution at pH 1.5. A higher soil-to-solution ratio of …

Approaches For Sample Characterization And Lithography With Nanoparticles Using Modes Of Scanning Probe Microscopy, Jayne C. Garno, Temitope O. Jegede, Kathryn B. Mckee, Melissia Porter, Autumn E. Webb, Jin Gyun Lee, Neepa Mk Kuruppu Arachchige, Justin R. Ragains, Noémie Elgrishi

Faculty Publications

Measurement and imaging modes of scanning probe microscopy (SPM) have been routinely applied for characterizing systems of nanoparticles; however the evolution of fabrication methods to prepare arrangements of nanoparticles remains a challenge. Reproducible fabrication of surface structures which integrate nanoparticles within ultra-small patterns will require innovative approaches to achieve high throughput and precision. Strategies for nanoscale lithography have been introduced for preparing defined arrangements of nanoparticles on surfaces based on physical or chemical interactions. For example, physisorption was employed for attaching nanoparticles based on colloidal lithography and site-directed assembly. Microfabricated atomic force microscope (AFM) tips with capillary channels have been …

Superconductivity In The Van Der Waals Layered Compound Ps2, Yan-Ling Li, Elissaios Stavrou, Qiang Zhu, Samantha M. Clarke, Yunguo Li, Hong-Mei Huang

Physics & Astronomy Faculty Research

van der Waals (vdW) layered compounds provided a fruitful research platform for the realization of superconductivity. However, a vdW layered superconductor with a high transition temperature (Tc) at ambient conditions is still rare. Here, using variable-composition evolutionary structure predictions, we systematically explored the stable compounds in the P-S system up to 20 GPa. Opposed to the complex stoichiometries at ambient conditions, only one compound, PS2, is predicted to be thermodynamically stable above 8 GPa. Strikingly, PS2 is a vdW layered material isostructural to 3R−MoS2 exhibiting a predicted Tc of around 11 K at ambient pressure, both in the bulk and …

Non-Einstein Viscosity Phenomenon Of Acrylonitrile–Butadiene–Styrene Composites Containing Lignin–Polycaprolactone Particulates Highly Dispersed By High-Shear Stress, Sing-Hoon Kim, Kisuk Choi, Kyouk Ryeol Choi, Taesung Kim, Jonghwan Suhr, Kwang Jin Kim, Hyoung Jin Choi, Jae-Do Nam

Mechanical Engineering Faculty Research

Lignin powder was modified via ring-opening polymerization of caprolactone to form a lignin–polycaprolactone (LPCL) particulate. The LPCL particulates were mixed with an acrylonitrile–butadiene–styrene (ABS) matrix at an extremely high rotational speed of up to 3000 rpm, which was achieved by a closed-loop screw mixer and in-line melt extruder. Using this high-shear extruding mixer, the LPCL particulate size was controlled in the range of 3395 nm (conventional twin-screw extrusion) down to 638 nm (high-shear mixer of 3000 rpm) by altering the mixing speed and time. The resulting LPCL/ABS composites clearly showed non-Einstein viscosity phenomena, exhibiting reduced viscosity (2130 Pa·s) compared to …

The Spectroscopic And Computational Exploration Of Sulfur Hydrogen Bonding, Andrew Yoonkeun Lee

Honors Projects

Hydrogen bonds are a subset of non-covalent interactions that occur between X-H — Y, in which X and Y are the very electronegative atoms. In our research, we examine the more unconventional hydrogen bond-like interactions of thiol (SH) containing molecules using vapor-phase infrared (IR) spectroscopy and ab initio computational chemistry. When the SH hydrogen bond donor complexes to a hydrogen bond acceptor, a red shift of the SH stretching mode emerges. An anharmonic oscillator local mode model is applied to the ethanethiol-trimethylamine dimer, and we determine that any IR evidence of dimerization in our experiment is likely obscured by the …

Kinetic Resolution Of Cyclic Secondary Azides, Using An Enantioselective Copper-Catalyzed Azide-Alkyne Cycloaddition, Juliana R. Alexander, Amy A. Ott, En Chih Liu, Joseph J. Topczewski

Chemistry Faculty Research & Creative Works

An enantioselective copper-catalyzed azide-alkyne cycloaddition (E-CuAAC) is reported by kinetic resolution. Chiral triazoles were isolated in high yield with limiting alkyne (up to 97:3 enantiomeric ratio (er)). A range of substrates were tolerated (>30 examples), and the reaction was scaled to >1 g. The er of a triazole product could be enhanced by recrystallization and the recovered scalemic azide could be racemized and recycled. Recycling the azide allows efficient use of the undesired azide enantiomer.

Conformational Studies Of Glucose Transporter 1 (Glut1) As An Anticancer Drug Target, Suliman Almahmoud, Xiaofang Wang, Jonathan L. Vennerstrom, Haizhen A. Zhong

Chemistry Faculty Publications

Glucose transporter 1 (GLUT1) is a facilitative glucose transporter overexpressed in various types of tumors; thus, it has been considered as an important target for cancer therapy. GLUT1 works through conformational switching from an outward-open (OOP) to an inward-open (IOP) conformation passing through an occluded conformation. It is critical to determine which conformation is preferred by bound ligands because the success of structure-based drug design depends on the appropriate starting conformation of the target protein. To find out the most favorable GLUT 1 conformation for ligand binding, we ran systemic molecular docking studies for different conformations of GLUT1 using known …

Study Of The Process Of Production Of Liquid Nitrogenfertilizers, A M. Reymov

Karakalpak Scientific Journal

The dependence of the changes in physico-chemical and rheological properties of solutions of the composition in systems [11,82%NH4CI +1,65% (NH4) 2SO4+6,76%К2S04+79,77%H2O]-CO(NH2)2 and [11,82%NH4CI+1,65%(NH4)2SO4+6,76%K2S04+ 79,77%H2O]-NH4NO3. On the basis of the studied diagrams "composition-properties" the optimal ratio of the components of the mother solution: nitrogen-containing fertilizers is 60:40 and 50:50, respectively, with the addition of urea and ammonium nitrate

Ab Initio Calculations Of Changes In Sulfur’S Orbital Energies And Sizes With Oxidation State As A Means Of Explaining Hypervalency, Anton V. Taraskin

Honors Projects

The energetics and orbital sizes of sulfur’s valence 3d and fluorine’s valence 2p orbitals were measured using a closed active space self-consistent field calculation to determine the degree of possible bonding available to sulfur’s 3d. It was determined that for orbital energies, the cc-pVXZ and aug sets converged hyperbolically onto a single energy value as X increased and that for both fluorine and sulfur orbital energies scaled down linearly with oxidation state. This resulted in a 0.47 hartree difference between the sulfur 3d and fluorine 2p orbitals at S0.6+ and F-0.1, far exceeding the energy gap between 3p and 2p …

Adaptable Xerogel-Layered Amperometric Biosensor Platforms On Wire Electrodes For Clinically Relevant Measurements, Lillian B. Hughes, Najwa Labban, Grace E. Conway, Julie A. Pollock, Michael C. Leopold

Chemistry Faculty Publications

Biosensing strategies that employ readily adaptable materials for different analytes, can be miniaturized into needle electrode form, and function in bodily fluids represent a significant step toward the development of clinically relevant in vitro and in vivo sensors. In this work, a general scheme for 1st generation amperometric biosensors involving layer-by-layer electrode modification with enzyme-doped xerogels, electrochemically-deposited polymer, and polyurethane semi-permeable membranes is shown to achieve these goals. With minor modifications to these materials, sensors representing potential point-of-care medical tools are demonstrated to be sensitive and selective for a number of conditions. The potential for bedside measurements or continuous monitoring …

Photoelectrochemical Catalysis Of Hydrogen Peroxide With Tellurium Containing Chromophores, James Eliott Lohman

Dissertations and Theses

Growing concerns over climate change and demand for energy worldwide have made development and implementation of alternative energy sources more necessary than ever. Many of the leading energy alternatives suffer from inconsistent energy production due to fluctuations in availability of natural resources, and the current methods of addressing the issue have tremendous ecological and social ramifications of their own. While fuels like hydrogen gas are providing some promise of relief, the scope of infrastructure changes necessary for implementation and the implicit hazards of the use of such fuels complicate their application as an immediate solution. However, hydrogen peroxide carries far …

Bending Ternary Dihalides: A Single Functional Form For Linearization Energies, Supreeth Prasad, Kelling J. Donald

Arts & Sciences Student Symposium

Introduction

Although the bonding in the symmetric groups 2 and 12 dihalides (MX2) has been studied extensively1,2, remarkably little work –experimental or theoretical – has been done on the mixed (ternary) dihalides, MXY. Previously, a criterion3,4 based on atomic softness (σ) was proposed for the bending of MX2 and MXY molecules. We extend this softness criterion on the slate of the mixed dihalides and the predicted separation is achieved between the bent and linear structures with almost the same cutoff, and with quasilinear species straddling the boundary. In this work, we report a complete assessment of the bonding preferences and …

Interfacial Amino Acids Support Spa47 Oligomerization And Shigella Type Three Secretion System Activation, Hannah J. Demler, Heather B. Case, Yalemi Morales, Abram R. Bernard, Sean J. Johnson, Nicholas E. Dickenson

Chemistry and Biochemistry Faculty Publications

Like many Gram-negative pathogens, Shigella rely on a type three secretion system (T3SS) for injection of effector proteins directly into eukaryotic host cells to initiate and sustain infection. Protein secretion through the needle-like type three secretion apparatus (T3SA) requires ATP hydrolysis by the T3SS ATPase Spa47, making it a likely target for in vivo regulation of T3SS activity and an attractive target for small molecule therapeutics against shigellosis. Here, we developed a model of an activated Spa47 homo-hexamer, identifying two distinct regions at each protomer interface that we hypothesized to provide intermolecular interactions supportingSpa47 oligomerization and enzymatic activation. Mutational analysis …

Synthesis Of Metal Oxide Surfaces And Interfaces With Crystallographic Control Using Solid-Liquid-Vapor Etching And Vapor-Liquid-Solid Growth, Beth S. Guiton, Lei Yu

Chemistry Faculty Patents

The present invention provides integrated nanostructures comprising a single-crystalline matrix of a material A containing aligned, single-crystalline nanowires of a material B, with well-defined crystallographic interfaces are disclosed. The nanocomposite is fabricated by utilizing metal nanodroplets in two subsequent catalytic steps: solid-liquid-vapor etching, followed by vapor-liquid-solid growth. The first etching step produces pores, or “negative nanowires” within a single-crystalline matrix, which share a unique crystallographic direction, and are therefore aligned with respect to one another. Further, since they are contained within a single, crystalline, matrix, their size and spacing can be controlled by their interacting strain fields, and the array …

Forty Years Of Progress In The Study Of The Hydrogen Bond, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The author looks back at developments over the last few decades concerning the H–bond. The list of atoms involved as proton donor and acceptor has broadened dramatically, including most electronegative atoms and even metals. The factors that control the transfer of the proton across the H–bond have been elucidated and show the importance of even minor changes in its geometry. Small stretches can shut down the transfer entirely, and certain bends can force a proton to transfer against a pK gradient. Along with the recognition that a CH..O interaction can represent a true H–bond, and one with strength comparable to …

Implementation Of Multivariate Artificial Neural Networks Coupled With Genetic Algorithms For The Multi-Objective Property Prediction And Optimization Of Emulsion Polymers, David Chisholm

Master's Theses

Machine learning has been gaining popularity over the past few decades as computers have become more advanced. On a fundamental level, machine learning consists of the use of computerized statistical methods to analyze data and discover trends that may not have been obvious or otherwise observable previously. These trends can then be used to make predictions on new data and explore entirely new design spaces. Methods vary from simple linear regression to highly complex neural networks, but the end goal is similar. The application of these methods to material property prediction and new material discovery has been of high interest …

Poly(Ester Amide) Particles For Controlled Delivery Of Celecoxib., Ian J Villamagna, Trent N Gordon, Mark B Hurtig, Frank Beier, Elizabeth R Gillies

Chemistry Publications

Many potential pharmacological treatments for osteoarthritis can result in undesirable side effects due to the systemic administration of drugs, making the direct delivery of drugs to joints an attractive alternative. Poly(ester amide)s (PEAs) have been shown to exhibit promising properties for the development of particle-based intra-articular delivery vehicles. However, a limited range of PEA structures has been investigated. In this study, we prepared and characterized the properties of two different PEA particles composed of l-phenylalanine, sebacic acid, and either 1,4-butanediol or 1,8-octanediol (PBSe and POSe, respectively). The anti-inflammatory drug celecoxib (CXB) was encapsulated into the particles. Despite minor structural differences, …

Monolayer Triphosphates Mp3 (M = Sn, Ge) With Excellent Basal Catalytic Activity For Hydrogen Evolution Reaction, Hong-Hui Wu, He Huang, Jie Zhong, Song Yu, Qiaobao Zhang, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

Atomically thin two-dimensional (2D) materials have received intense research interest due to their novel properties and promising applications in nanodevices. By using density functional theory (DFT) calculations, we investigate catalytic activities of several newly predicted two-dimensional (2D) triphosphides GeP₃, SnP₃ and InP₃ monolayers for hydrogen evolution reaction (HER). The calculation results show that GeP₃ and SnP₃ monolayers are active catalysts for HER with suitable free energy of hydrogen adsorption in the basal plane. In particular, the Gibbs free energy of hydrogen adsorption (ΔG_H*) of GeP₃ is 0.024 eV, a value even …

Natural Kinds And Ceteris Paratis Generalizations: In Praise Of Hunches, W. Christropher Boyd, Richard N. Boyd

Chemistry Faculty Publications

According to stereotypical logical empiricist conceptions, scientific findings are approximately true (or perhaps true ceteris paribus) law-like generalizations used to predict natural phenomena. They are deployed using topic-neutral, generally reliable inferential principles like deductive or statistical inferences. Natural kinds are the kinds in such generalizations. Chemical examples show that such conceptions are seriously incomplete. Some important chemical generalizations are true often enough, even though not usually true, and they are applied using esoteric topic- and discipline-specific inference rules. Their important methodological role is to underwrite often-enough reliable, often socially implemented, scientifically informed guessing about chemical phenomena. Some chemical natural …