Chemistry Commons^™

Synthesis Of Novel Dna-Binding Polyamides To Prevent Cancer-Related Gene Overexpression, Huy Q. Nguyen

Dissertations

Pyrrole-imidazole polyamides (PIPs) are nanomolecular compounds designed to fit in the tight space of DNA minor grooves. As analogs of Netropsin and Distamycin A, PIPs are specifically designed to recognize the base pairs of DNA sequences. PIPs have many biological applications, such as regulating gene expression, biochemistry pathway regulations, and suppressing the development of cancer cells. SETMAR gene is the chimeric fusion of the SET domain with the mariner transposase. Its protein (Metnase) has functions involving DNA repairs in the NHEJ pathway, regulating gene expression, DNA decatenation, etc. Despite not having an active transposable element, SETMAR still has an unknown …

Fine Tuning The Pore Surface In Zirconium Metal−Organic Frameworks For Selective Ethane/Ethylene Separation, Yuchen Hu, Yanshu Shi, Yi Xie, Rebecca Shu Hui Khoo, Christian Fiankor, Xu Zhang,, Banglin Chen, Jian Zhang

Department of Chemistry: Faculty Publications

Ethylene is an important chemical feedstock for production of polymers and high-value organic chemicals, and yet its conventional purification process is plagued with high consumption of energy. Metal−organic frameworks (MOFs) provide a suitable adsorption platform for selective ethane/ ethylene separation thanks to their structural diversity, tunable pore characteristics, designable pore sizes, and high pore volumes. Although there are empirical design rules like avoiding open metal sites and creating nonpolar pore surfaces for development of adsorptive MOFs, it is still challenging to design robust MOFs that can realize direct ethane-selective separation. Herein, we systematically designed and synthesized three Zr-MOFs based on …

Origin Of The Second-Order Proton Catalysis Of Ferriin Reduction In Belousov-Zhabotinsky Reactions: Density Functional Studies Of Ferroin And Ferriin Aggregates With Outer Sphere Ligands Sulfate, Bisulfate, And Sulfuric Acid, Sara C. Mccauley, Rainer Glaser

Chemistry Faculty Research & Creative Works

The detailed mechanisms of Belousov-Zhabotinsky oscillating reactions continue to present grand challenges, even after half a century of study. The origin of the pH dependence of the oscillation pattern had never been rigorously identified. In our recent kinetic study of one of the key Belousov-Zhabotinsky reactions, the iron-catalyzed bromate oxidation of malonic acid, compelling agreement between experiments and kinetic simulations was achieved only with the inclusion of second-order proton catalysis of the reduction of the [Fe(phen)₃]³⁺ species. After exhausting all other avenues in search of an explanation of this proton catalysis, we considered the possibility that the …

2022 Scas Annual Meeting Program And Bulletin

Journal of the South Carolina Academy of Science

No abstract provided.

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.

Environmental Bacteriophage Detection On Coastal Carolina University Campus, Madison Gentilo, Hailey Oldfield, Gavin Ockert, Paul E. Richardson

Journal of the South Carolina Academy of Science

Bacteriophages are viruses that infect bacteria. These viruses are found ubiquitously in the environment and are more abundant than any living organism on Earth, including bacteria. Eleven sites are designated for weekly sample collection on the campus of Coastal Carolina University. Water samples are filtered and amplified using strains of E. coli B and E. coli K12 to allow potential coliphages in the sample to proliferate to detectable levels. Plaque assays are used as a microbial screen for the presence of bacteriophage. Samples that test positively using the microbial test are analyzed through a molecular test using PCR to identify …

3,6-Dimethoxyxanthone From 2,2’,4,4’- Tetrahydroxy-Benzophenone Via Microwave-Assisted Annulation, Sarah E. Knisely, Faith R. Rosario, Salem F. Gebeyehu, Paige E. Heiple, Robert E. Lee Sr

Journal of the South Carolina Academy of Science

Xanthones are tricyclic aromatic compounds that have multiple pharmacological uses due to their anti-tumor, antioxidant, anti-inflammatory, anti-bacterial, and potentially chemopreventive properties. The target of this research was to optimize a two-step synthesis of 3,6-dimethoxyxanthone (3) from 2,2’,4,4’-tetrahydroxy-benzophenone (1) via microwave-assisted (200 °C, 30-40 min., 150 W) sodium acetate-catalyzed annulation. The product, 3,6-dihydroxyxanthone (2), was then methylated to (3) using dimethyl sulfate (DMS) and sodium carbonate in acetone at reflux. The product yields were 93% (>99% purity) for (2) and 94% (>99% purity) for (3). Characterization was accomplished using ¹H NMR, FTIR, melting point, TLC, HPLC, and GCMS. …

The Effects Of Human Behavioral Changes Due To The Covid-19 Pandemic On The Reservoir Of Lytic Escherichia Coli And Staphylococcus Aureus Bacteriophage On Humans At A South Carolina University, Korinne M. Swanson, Owen R. Smith, Paul E. Richardson

Journal of the South Carolina Academy of Science

Bacteriophages are viruses, whose unique ability to infect and lyse bacterial cells may provide valuable insight for evading the repercussions of a post-antibiotic era in medicine. This study isolated and characterized Escherichia coli and Staphylococcus aureus bacteriophage on students and faculty at Coastal Carolina University as a means to understand the viability of human bacteriophage reservoirs for bacteriophage therapy. From September 2021 to March 2022, nasal and postauricular swab samples and a behavioral survey were collected from ninety-three randomly selected participants. Additionally, sixteen participants contributed nasal and postauricular swab samples and a behavioral survey on a monthly basis in a …

Reconstruction Of Exchange–Correlation Potentials From Their Matrix Representations, Yan Oueis, Viktor N. Staroverov

Chemistry Publications

Within a basis set of one-electron functions that form linearly independent products (LIPs), it is always possible to construct a unique local (multiplicative) real-space potential that is precisely equivalent to an arbitrary given operator. Although standard basis sets of quantum chemistry rarely form LIPs in a numerical sense, occupied and low-lying virtual canonical Kohn–Sham orbitals often do so, at least for small atoms and molecules. Using these principles, we construct atomic and molecular exchange–correlation potentials from their matrix representations in LIP basis sets of occupied canonical Kohn–Sham orbitals. The reconstructions are found to imitate the original potentials in a consistent …

Interfacial Oxidative Oligomerization Of Catechol, Marcelo I. Guzman, Elizabeth A. Pillar-Little, Alexis J. Eugene

Chemistry Faculty Publications

The heterogeneous reaction between thin films of catechol exposed to O₃(g) creates hydroxyl radicals (HO^•) in situ, which in turn generate semiquinone radical intermediates in the path to form heavier polyhydroxylated biphenyl, terphenyl, and triphenylene products. Herein, the alteration of catechol aromatic surfaces and their chemical composition are studied during the heterogeneous oxidation of catechol films by O₃(g) molar ratios ≥ 230 ppbv at variable relative humidity levels (0% ≤ RH ≤ 90%). Fourier transform infrared micro-spectroscopy, atomic force microscopy, electrospray ionization mass spectrometry, and reverse-phase liquid chromatography with UV−visible and mass spectrometry detection …

Direct Measurement Of Stokes–Einstein Diffusion Of Cowpea Mosaic Virus With 19 Μs-Resolved Xpcs, Kacper Switalski, Jingyu Fang, Luxi Li, Miaoqi Chu, Erik Sarnello, Pete Jemian, Tao Li, Qian Wang, Qingteng Zhang

Faculty Publications

Brownian motion of Cowpea mosaic virus (CPMV) in water was measured using small-angle X-ray photon correlation spectroscopy (SA-XPCS) at 19.2 mu s time resolution. It was found that the decorrelation time tau(Q) = 1/DQ(2) up to Q = 0.091 nm(-1). The hydrodynamic radius R-H determined from XPCS using Stokes-Einstein diffusion D = kT/(6 pi eta R-H) is 43% larger than the geometric radius R-0 determined from SAXS in the 0.007 M K3PO4 buffer solution, whereas it is 80% larger for CPMV in 0.5 M NaCl and 104% larger in 0.5 M (NH4)(2)SO4, a possible effect of aggregation as well as …

Contra-Thermodynamic Halolactonization Of Lactam-Tethered 5-Aryl-4(E)-Pentenoic Acids For The Flexible And Stereocontrolled Synthesis Of Fused Lactam-Halolactones, Timothy K. Beng, Claire Borg, Morgan J. Rodriguez

All Faculty Scholarship for the College of the Sciences

Halolactonization of alkenoic acids enables the construction of oxygen-heterocycles via intramolecular halonium-induced nucleophilic addition. Although the literature is currently inundated with halolactonizations of 5-aryl-4(E)-pentenoic acids that predictably afford the 6-endo cyclization adducts, methods that reliably alter the innate regioselectivity bias to instead deliver the thermodynamically less favored 5-exo cyclization products are relatively rare. Here, we attempt to bridge this gap and have found mild conditions for contra-thermodynamic halolactonization of lactam-tethered 5-aryl-4(E)-pentenoic acids that lead to the formation of trans-fused lactam-γ-lactones. The natural proclivity for these 5-aryl-4(E)-pentenoic acids to undergo 6-endo cyclization is overridden and 5-exo-trig cyclization predominates. The success of …

Solvation Of Large Polycyclic Aromatic Hydrocarbons In Helium: Cationic And Anionic Hexabenzocoronene, Miriam Kappe, Florent Calvo, Johannes Schöntag, Holger F. Bettinger, Serge Krasnokutski, Martin Kuhn, Elisabeth Gruber, Fabio Zappa, Paul Scheier, Olof E. Echt

Faculty Publications

The adsorption of helium on charged hexabenzocoronene (Hbc, C₄₂H₁₈), a planar polycyclic aromatic hydrocarbon (PAH) molecule of D_6h symmetry, is investigated by a combination of high-resolution mass spectrometry and classical and quantum computational methods. The ion abundance of He_nHbc⁺ complexes versus size n features prominent local anomalies at n = 14, 38, 68, 82, and a weak one at 26, indicating that for these “magic” sizes the helium evaporation energies are relatively large. Surprisingly, mass spectra of anionic He_nHbc^– complexes feature a different set of anomalies, namely at …

Visualization For Better Learning In Chem 120, Ngoc (Valerie) Tran, Jeffrey A. Hansen

Annual Student Research Poster Session

Many concepts in organic chemistry relate to spatial reasoning and the ability to translate two-dimensional representations into a three-dimensional mental image. It is critical that students gain a thorough understanding of visualizing atoms, orbitals and their interactions in three dimensions. By developing an E-book with computer graphics, 3D animations, H5P films, and online apps, we hope to enhance Depauw students' learning experiences in the CHEM 120 course. In this project, we would like to demonstrate 3D representations of chemical concepts to help students form these 3D mental images from a 2D surface. The process includes concept developing, storyboarding, 2D and …

Method Development For The Analysis Of Pharmaceuticals Using High Performance Liquid Chromatography, To Uyen (Anita) Nguyen, Richard Martoglio

Annual Student Research Poster Session

Since 2013, there have been 1500 reports of counterfeit drugs to WHO, especially from African, American, and European regions 1. Tackling the problem of poor drug quality, the Distributed Pharmaceutical Analysis Lab (DPAL) provides a quality analysis to quantify active pharmaceutical ingredient contents with a goal to trigger a report to the MRA or WHO2. With the support of DPAL, we would like to perform a series of chromatography experiments using the HPLC in order to identify and quantify the active pharmaceutical ingredients (API) of Amoxicillin and Ciprofloxacin.

Chemweb: A 2d Molecular Builder Game, Suleman Bashir Baloch, Jeffrey A. Hansen

Annual Student Research Poster Session

The research is based on the development of a 2D molecular builder game for CHEM 120 students. The game allows students to draw and check their structures for a given formula against a database of possible correct structures. The game consists of 8 levels, each based on drawing the maximum possible isomers from a given chemical formula. It is created as a web-based application on React.js. The project shall allow greater liberty and ease to students in drawing structures. In addition, they shall be able to perform self-check for drawn structures which will significantly minimize the assistance required from instructors …

Impact Of Urea On Size And Red-Edge Emission Spectroscopy Of Reverse Micelles, Tran Nguyen, Nancy E. Levinger, Bridget Gourley Ph.D

Annual Student Research Poster Session

We use reverse micelles (RMs) as our model system to study the impact of osmolytes on water at the nanoscale. Reverse micelles are characterized by w0 = [polar component]/[surfactant]. In our experiment, we focus on 5 different w0 (w0 = 1, 5, 10, 20, 40) and 3 concentrations of urea (0.5M, 1M, 2M). The Dynamic Light Scattering (DLS) illustrates a linear relationship between reverse w0 (the ratio) and size. Additionally, the DLS data indicates that the impact of osmolytes on size for small reverse micelles is not significant. Furthermore, Red-Edge Emission Spectroscopy shows a bigger impact on emission for smaller …

High Performance Liquid Chromatography (Hplc) For Ampicillin And Cefuroxime, Patrick Mcinerney, Richard Martoglio

Annual Student Research Poster Session

Appropriate levels of an active pharmaceutical ingredient (API) in medicines must be present in a medical product for the patient to receive therapeutic value. High performance liquid chromatography (HPLC) was used to develop a methodology to test for the API in Ampicillin and Cefuroxime drugs. Following the regulations of the Distributed Pharmaceutical Analysis Lab (DPAL) out of Notre Dame system sustainability requirements linearity, precision, accuracy/range, spike/degraded spike, limit of detection /quantitation, tailing factor, and number of theoretical plates were experimentally determined to meet the excepted standards.

Development Of A Method For Evaluating Absorption Spectra Irregularities: 3-Methylcyclopentanol And 4-Methylcyclohexanol

Journal of Interdisciplinary Undergraduate Research

Accurate rate constant values are critical for understanding chemical reaction pathways involving cyclopentenyl and cyclohexenyl cation intermediates. One approach for determining this essential kinetic information follows the time rate of change of such cations using UV-visible spectrophotometry. However, the obtained absorption spectra often show asymmetric irregularities such as shoulders due to interfering side reactions. The aim of this exploratory study was to develop a method of interpreting UV-visible spectra that provides accurate rate constant values in addition to clarifying the cause of signal abnormalities. In this investigation, changes in spectra of the cation intermediates were followed over the course of …

The Formation Of Monosubstituted Cyclopropenylidene Derivatives In The Interstellar Medium Via Neutral-Neutral Reaction Pathways, Athena R. Flint, Ryan C. Fortenberry

Faculty and Student Publications

Five substituted cyclopropenylidene derivatives (c-C3HX, X = CN, OH, F, NH2), all currently undetected in the interstellar medium (ISM), are found herein to have mechanistically viable, gas-phase formation pathways through neutral-neutral additions of ·X onto c-C3H2. The detection and predicted formation mechanism of c-C3HC2H introduces a need for the chemistry of c-C3H2 and any possible derivatives to be more fully explored. Chemically accurate CCSD(T)-F12/cc-pVTZ-F12 calculations provide exothermicities of additions of various radical species to c-C3H2, alongside energies of submerged intermediates that are crossed to result in product formation. Of the novel reaction mechanisms proposed, the addition of the cyano radical …

Large Variability And Complexity Of Isothermal Solubility For A Series Of Redox-Active Phenothiazines†, Anton S. Perera, Thilini Malsha Suduwella, Nuwan Harsha Attanayake, Rahul Kant Jha, William L. Eubanks, Ilya A. Shkrob, Chad Risko, Aman Preet Kaur, Susan A. Odom

Chemistry Faculty Publications

The development of redox-active organic molecules (ROM) with large solubilities in all states of charge in organic electrolytes is imperative to the continued development of non-aqueous redox flow batteries. The capability to a priori predict ROM solubility would be a game changer, allowing for a move away from time and resource consuming trial-and-error approaches to materials design and deployment. However, it is not presently clear that such predictions are generally possible, even for chemically related ROM, given the large number of physicochemical factors in play. Here we use quantitative structure–property relationships (QSPR) to examine solubility trends for a set of …

Symmetry Breaking Charge Transfer In Dna-Templated Perylene Dimer Aggregates, Katelyn M. Duncan, Donald L. Kellis, Jonathan S. Huff, Matthew S. Barclay, Jeunghoon Lee, Daniel B. Turner, Paul H. Davis, Bernard Yurke, William B. Knowlton, Ryan D. Pensack

Chemistry and Biochemistry Faculty Publications and Presentations

Molecular aggregates are of interest to a broad range of fields including light harvesting, organic optoelectronics, and nanoscale computing. In molecular aggregates, nonradiative decay pathways may emerge that were not present in the constituent molecules. Such nonradiative decay pathways may include singlet fission, excimer relaxation, and symmetry-breaking charge transfer. Singlet fission, sometimes referred to as excitation multiplication, is of great interest to the fields of energy conversion and quantum information. For example, endothermic singlet fission, which avoids energy loss, has been observed in covalently bound, linear perylene trimers and tetramers. In this work, the electronic structure and excited-state dynamics of …

The Coastal Monitor: Vol. 9 No. 5, John Tanacredi Ph.D.

The Coastal Monitor

There are a multitude of lessons learned from the last 3 years of the Covid-19 pandemic. But one truly stands out ...the total lack of understanding of the basic chemistry associated with the nitrogen cycle, which in Suffolk County, NY, continues to be declared as the “evil-nitrogen”. The major source of nitrogen into the water body comes from the atmosphere which is the predominate constituent of the air we breathe79% nitrogen. Nitrogen compounds contribution to eutrophication in freshwater (ponds & lakes) systems is legendary and, the concentration of nitrogen in marine waters has always been known as a limiting agent …

Determination Of Nitrate In Aqueous Media, Ebony Arauz Tellez, John Bohannon, Rebecca Mills, Virginia Tam, Isabelle Villarreal, Melissa C. Rhoten

Fall Showcase for Research and Creative Inquiry

Determining the amount of inorganic ions in aqueous media is important in the food industry and environmentally. In the environment high levels of ions like nitrate (NO₃^-), nitrite (NO2^-), and phosphate (PO₄^3-) can lead to unhealthy conditions for aquatic species. Similarly, high levels of nitrate and nitrite can cause health issues in humans. One method for determining nitrate levels in aqueous samples involves reducing the nitrate species to nitrite via a redox reaction with finely divided zinc powder followed by conversion to a diazonium salt and complexation with 1-napthylamine to form a …

Cultivating Teacher Expertise In The Landscape Of Green Chemistry: The Development Of Pedagogical Content Knowledge In Beyond Benign’S Lead Teacher Program, Philip Charles Nahlik

Dissertations

Chemistry Education, Green Chemistry, Pedagogical Content Knowledge, Professional Learning Communities, Sustainability, Teacher Training

Investigation Of Carbon Dioxide Oxidation Reaction Pathways On Rh(111) Via Reflection Absorption Infrared Spectroscopy (Rairs), Elizabeth A. Jamka

Dissertations

CO oxidation, RAIRS, Rh(111), Surface Science, UHV

Using Ftir-Atr And Chemometric Methods To Detect Sucrose Adulteration In Commercial Honey Samples, Dylan T. Roberts, Kevin Kittredge

Virginia Journal of Science

Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR–ATR) was used to analyze pure and adulterated honey samples. The FTIR spectra was analyzed using principal component analysis (PCA) and partial least squares (PLS) regression analysis to determine if these methods could differentiate between pure, commercial, and sucrose-adulterated honey samples. PCA showed a clear distinction between pure and adulterated honey samples. Commercial honey samples showed clustering around the unadulterated samples. PLS regression analysis correctly identified 81.8% of the standards and samples used in the PCA analysis. The five commercial samples were tested and shown to have a concentration of less than 3% adulterant, …

Polarclean & Dimethyl Isosorbide: Green Matches In Formulating Cathode Slurry, Amrita Sarkar, Richard May, Zoren Valmonte, Lauren E. Marbella

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

In this study, two green organic solvents are reported in LiNi1/3Co1/3-Mn1/3O2 (NMC111)-based slurry preparation and subsequent cathode fabrication for Li ion batteries. NMC111, conductive carbon and poly(vinylidene fluoride) binder composite slurries prepared with methyl-5-(dimethylamino)-2-methyl-5-oxopentanoate (Polar-Clean) and dimethyl isosorbide (DMI) exhibit mechanically stable, crack-free uniform coating structures. Both slurries showed similar shear-thinning viscosity behavior that suggests similar processibility during electrode casting and coating. When used as the cathode in Li/NMC111 half cells, the electrode slurries prepared with Polar-Clean show promising electrochemical performance metrics with an average specific charge capacity of 155 ±-1mA h g-1 at C/10 over 100 cycles, comparable to …

Is It Useful? Orthophosphate Mapping Of An Excavated Cellar Of A Mid 1700’S Tavern In New London Va, Thomas M. Bender, Randy Lichtenberger

Faculty Publications and Presentations

The partially backfilled cellar of Mead’s Tavern (VDHR # 015-0120) a circa 1760’s building in New London Virginia, was studied by orthophosphate (PO₄³) mapping of the recently exposed, culturally sterile, subsoil floor. Prior studies of the cellar had exposed a hearth along with features that were speculated to be wall partitions for subdivision of the cellar. The full intended purpose for those exposed features is unknown. To further probe that exposed subsoil prior to a major engineering stabilization of the tavern’s foundation, a chemical mapping of surface PO₄^3- levels in the cellar was done. The …

Converting Hydrazone-Based Photoswitches Into Functional Materials, Sirun Yang

Dartmouth College Ph.D Dissertations

The development of new classes of molecular switches with enhanced performance and brand-new functionalities enables practitioners to push the frontiers of adaptive materials. In the realm of photoswitches, the bistability of hydrazones (i.e., molecules that incorporate the C=N-NH functional group) allows for the kinetic trapping of polymer and supramolecular assemblies resulting in multistate actuation and emergent phenomena that are not tractable with other photoswitches. This property has transformed hydrazone photoswitches into powerful tools that can be used in understanding fundamental molecular interactions and how to apply them in modulating the physicochemical properties of materials.

Progressing from disordered to …