Physical Sciences and Mathematics Commons^™

Photophysical And Photochemical Processes In Small Molecules And Materials For Solar Energy Conversion, Ethan Lambert

Honors Theses

The work covered in this thesis all falls under the theme of photophysical processes after light and matter interact. Those of primary interest are Raman scattering induced vibrations and excited state dynamics probed by transient absorption spectroscopy. Small molecules are studied with Raman spectroscopy and computational chemistry. These studies unearth the shifts in vibrational frequency as a function of charge transfer or receipt and how a quantitative assay of natural orbital populations and delocalization can offer both the nature and magnitude of this charge transfer. Further, a method is presented that builds upon previous work within the academic family tree; …

Structural Integrity And Stability Of Dna In Ionic Liquid And Near-Infrared Indolizine Squaraine Dye, Ember Yeji Suh

Honors Theses

Luminol, the most common presumptive test for blood at a crime scene, has multiple issues, such as false positive results with chemical agents, no luminescence due to “active oxygen” cleaning agents on bloodstains, and inability to penetrate textile materials. A combination of indolizine squaraine dye and ionic liquid (IL), or Dye Enhanced Textile Emission for Crime Tracking (DETECT), have shown potential to address these issues. The purpose of this study was to assess the binding mechanism of CG (1:1) and SO₃SQ dye to HSA and how the mechanism can explain the W214 fluorescence quenching effect and to determine …

Investigating Reactivity Of Artificial Copper Peptides With Small Molecules, Allyson Bryant

Honors Theses

The design of artificial enzymes has been a topic of significant interest in the field of biochemistry, as they can provide new opportunities for catalytic processes and drug development. De novo protein design has emerged as a promising approach to create such enzymes, and the study of metalloproteins, particularly copper-binding peptides, has become a focus of this research. This thesis investigates the reactivity of a mutated copper-binding peptide, I5A-3SCC, with oxygen and its implications in the development of artificial enzymes.

The parent peptide, 3SCC, was mutated by replacing Isoleucine residues with smaller Alanine side chains, which was hypothesized to enhance …

Ab Initio Study Of The Rotation Of The C≡C Group In Benzvalyne, Advait Praveen

Honors Theses

For benzvalyne, we have characterized the minima and transition states of the molecule using the B3LYP, MP2, and M06-2X methods and aug-cc-pVTZ basis set. This was done by calculating the energy of the molecule while rotating the alkyne bond contained within it. After the initial rotation, optimized parameters for the molecule are found. Following this, imaginary frequencies were attempted to be found at the local maximum produced by the graph of the Energy v. rotation angle. Should the negative frequencies be found, the energy of the molecule will be characterized by the CCSD (T) method and aug-cc-pVQZ basis sets. This …

Synthetic Investigations In Chemical Probe Development Part 1: Design And Synthesis Of Novel Triton X-405 Adenosine Conjugates; Part 2: Synthesis Of 2,8-Dihydroxychrysene, Rachel Irene Hammond

Honors Theses

Although not drugs themselves, chemical probes are a necessary tool in biomedical research for the interrogation of biological systems. In the present synthetic investigation, two chemical probes were developed – a Triton X-405 adenosine conjugate (TX-405A) and 2,8-dihydroxychrysene. The designed TX-405A conjugate was generated in four steps through tosylation and amination of TX-405 such that EDC-coupling of TX-amine with 2’,3’-Isopropylidene adenosine-5’-carboxylic acid afforded TX-405A following acetonide deprotection. The development of TX-405A represents the first report of the synthesis and utilization of a detergent-linked dosimeter. The synthesis of 2,8-dihydroxychrysene provided an in-depth exploration on the unique reactivity of chrysene. The desired …

Covalent Modification Of Recombinant Protein With Reactive Thiols, Sawyer Dulaney, Bailey Taylor

Honors Theses

Many diseases cause chronic and painful inflammation in different body systems. One of the front-line drug classes to treat such inflammation is Nonsteroidal Anti-Inflammatory Drugs (NSAIDs). Despite the benefits of oral administration of NSAIDs, there are drawbacks to their long-term usage because they can cause detrimental effects on off-target systems in the body such as the liver, kidney, or the lining of the intestinal tract. An alternative to NSAIDs is the usage of hydrogels for targeted drug delivery. Hydrogels can provide drug delivery in a specific portion of the site of inflammation, thus allowing higher doses of medication to be …

The Design Of A Pcr-Based Assay To Detect And Isolate The Serine Palmitolytransferase Gene From Environmental Bacteria, Lana Taylor

Honors Theses

Sphingolipids are a natural class of lipids that function as structural elements of cell membranes and signaling molecules for important cellular activities such as cell growth, differentiation, apoptosis, recognition, and adhesion. These lipids can be found universally in eukaryotic cells as well as some species of bacteria, such as those found in the human gut microbiome and in the environment in soils. Though sphingolipid production is rare in bacteria, both eukaryotic and prokaryotic sphingolipid biosynthesis begin with the condensation of serine and palmitoyl CoA into 3-ketodihydrosphingosine catalyzed by the enzyme serine palmitoyltransferase (SPT). In recent years, several studies have shown …

Synthesis And Characterization Of Redox-Active Multidentate Ligands For Catalytic C-H Bond Oxidation And Carbon Dioxide Reduction, Caroline Hodge

Honors Theses

This thesis focuses on two research projects. The first project reported in Chapter 1 involves the synthesis and application of a tetradentate ligand (2-(1,1-di(pyridin-2-yl)ethyl)-1,10-phenanthroline, PhenPY2Me) that is metalated with iron to give a catalyst capable of carbon-hydrogen (C-H) bond oxidation. C-H bond oxidation provides a method that may allow some transformations in organic syntheses to be streamlined. The mononuclear iron complex supported by PhenPY2Me was found to dimerize in the presence of O₂ in a non-coordinating solvent. These iron complexes and a previously reported system were assessed and compared in C-H bond oxidation with model substrates using the sacrificial …

A Theoretical Study Of Synchronous Proton Transfer In (Hf)N, (H2O) N, And (Hcl) N Where N = 3, 4, 5, Johnny Yang

Honors Theses

For (HF)_n, (H₂O)_n, and (HCl)_n (n = 3 − 5), we have rigorously characterized the structures for the minima and transition states for synchronous proton transfer (SPT) with the CCSD(T) method and aug-cc-pVTZ basis set. The electronic barrier heights (∆E^†) associated with these transition states have also been computed with the explicitly correlated CCSD(T)-F12 method and the aug-cc-pVQZ-F12 basis set (abbreviated aQZ-F12). (HCl)_n (n = 3 − 5) SPT transition states have not been previously identified to the best of our knowledge, and they have been found …

One-Pot Synthesis Of Disubstituted Primary Amines From Nitriles Via Grignard Addition And Metal-Alcohol Reduction, Joshua Peltan

Honors Theses

The process of developing a working base case procedure for a novel one-pot-two-step synthesis of primary amines from Grignard reagents, nitriles, sodium metal or alkali metal loaded silica gel, and alcohol is described. Initial steps towards applying the process broadly are detailed. The process has the potential to be an affordable, convenient, safer, greener, and more accessible alternative to exiting methods of accomplishing the same transformation. The reaction scheme has been proven to provide yields and purity comparable to existing methods for certain pairs of substrates; however, its utility as a general-purpose method for transforming arbitrary pairs of Grignard reagent …

Determination Of Metals And Microplastics In Sediment From Oyster Reefs In The Mississippi Sound, Shelby Goza

Honors Theses

This research centers on the determination of metals (Cd, Pb, V, Cr, Mn, Fe, Co, Ni, Cu) and microplastics (MPs) in marine sediment from oyster reefs in the Mississippi Sound Estuary. Oysters (Crassostrea virginica) are a vital part of the Gulf Coast economy, but their population has dramatically declined in recent years due to multiple stressors, including oil spills and fluctuations in salinity from flooding. Increasingly frequent flooding events also introduce high loads of MPs and sediments containing heavy metals from the Mississippi River. These pollutants can have deleterious effects on oyster biology; however, they have not been adequately …

Applications Of Sodium Azide In The Synthesis Of Tetrazines And Hydrolysis Reactions, My Le

Honors Theses

The inverse electron demand Diels−Alder cycloadditions of heterocyclic azadienes have provided a robust methodology for synthesizing highly substituted and functionalized heterocycles. It is widely used in organic synthesis and the pharmaceutical industry in the divergent construction of screening libraries and bioorthogonal conjugation. Each heterocyclic azadiene was found to possess a unique reactivity toward different classes of dienophiles, display predictable modes of cycloaddition, and exhibit substantial substituent electronic effects impacting their intrinsic reactivity and cycloaddition regioselectivity. Synthesis of 1,2,4,5-tetrazine has been reported in the literature since the late 19th century, showing scientists' tremendous interest in its application.

Herein we attempt to …

Computational Investigation Of Stellar Cooling, Noble Gas Nucleation, And Organic Molecular Spectra, Jax Dallas

Honors Theses

Since the advent and optimization of the Hartree-Fock method, quantum chemistry has been utilized to investigate systems operating on timeframes and environments traditionally unavailable to bench-top chemistry. As computational methods have grown more robust and less time consuming, quantum chemistry has been utilized to investigate a range of fields, including the steadily growing discipline of computational astrochemistry. Through the lens of computational astrochemistry, chemistry that occurred billions of years ago can be explored with equal clarity to that which is currently happening in the cosmos. The work presented throughout this thesis is a series of investigations into different timeframes of …

Effects Of Halogen Bonding On 13c Nmr Shifts Of Various Tolan Species, Anthony Lybrand

Honors Theses

Halogen bonding is slowly becoming a more and more useful part of the world of chemistry and is beginning to be incorporated into various aspects of the chemical industry. This study’s purpose is to determine whether or not halogen bonding can cause any effect in the 13C NMR shifts. The specific purpose of this study is to determine whether these chemical shifts change when a Lewis Base is added to the dissolved sample. In order to do this, the tolan species (4-iodotolan and 4-chlorotolan) had to be synthesized. Once synthesized, the tolan species were analyzed via NMR. NMR data indicated …

Effects Of Crowding Agents On I-Motif Dna, Hayden Brines

Honors Theses

Deoxyribonucleic acid (DNA) is a well-known double stranded, helical, biological molecule. In addition to its more commonly known structure, DNA can also form more complicated structures like G-quadruplexes and i-motifs (iM). The iMs are formed by cytosine rich DNA and are a four stranded structure that is typically looped around itself. The iM formation is typically pH-dependent and is favored in more acidic conditions; the pKa value is approximately 6.5. This pKa value allows for potential in vivo formation, since the cells have a pH of approximately 7.3. Due to this, iMs are thought to be powerful, innovative molecules for …

End Group Modification Of Linear Dendritic Block Copolymers (Ldbcs), Chinwe Udemgba

Honors Theses

Linear dendritic block copolymers are amphiphilic molecules that consist of a dendritic hydrophilic portion and a linear hydrophobic portion. Its unique ability to self-assemble into spherical nanoaggregates while having the potential to uptake and transport both hydrophilic and hydrophobic drugs makes these polymers an item of interest in regard to the drug delivery field. The synthesis of polyamidoamine-polylactide linear dendritic block copolymers was designed to address the common issues in drug delivery systems, including problems in permeability, solubility, stability, specificity, and retention. Though this linear dendritic block copolymer has previously been synthesized in our lab with cationic amine surface functionalities, …

Synthesis Of A Dd-Π-Aa Organic Dye For Dye-Sensitized Solar Cells, Hope Lovell

Honors Theses

This project investigates the synthesis of a DD-π-AA (dual donor/dual acceptor) organic dye as a potential sensitizer for dye-sensitized solar cells (DSCs). The design of this dye was based off previous research that found dual donor/dual acceptor dyes exhibited promising results when used in a DSC. The donor groups, acceptor groups, and π-bridge were chosen for their stability, ability to absorb in the near-infrared (NIR) region, and intramolecular charge transfer (ICT) abilities.

While many components of the dye were synthesized, the final stages of the synthetic scheme were not completed due to the loss of time from COVID-19. Had the …

A Conductivity Analysis Of A Newly Synthesized Poly(Ethylene Glycol) Methyl Ether Hydroxide Electrolyte, Sarah Marie Peterson

Honors Theses

This thesis investigates the synthesis and conductive properties of a Poly (ethylene glycol) methyl ether-based polymer electrolyte. The goal of the synthesis is to enhance the hydroxide ion conduction properties of the polymer with its cationic groups attached. The MePEG backbone contained seven ethylene glycol groups and was modified to substitute the hydroxide group in the MePEG with trimethylamine. In addition, the bromide added in the synthesis was exchanged for hydroxide ions to allow for the transportation of hydroxide ions in polymeric electrolytes that can be used in Anion Exchange Membrane Fuel Cells. The newly synthesized polymer was compared to …

Lc-Ms/Ms Method Development And Analysis Of Tricyclic Antidepressants In Human Plasma, Shahbaz Gul

Honors Theses

Depression has become one of the most prominent problems in society, disrupting both personal and social lives. Tricyclic antidepressants (TCAs) were first developed in the 1950’s and became some of the leading anti-depressant medications on the market later that decade. Today, newer anti-depressants have risen to the forefront, being safer and having a lower side-effect probability. Nonetheless, TCAs continue to be prescribed for severe depression, especially in cases where the newer anti-depressants have failed. However, TCAs are still highly potent, the toxicity associated with these compounds cannot be ignored. They have considerable cardiovascular and neurological toxicity, and in the event …

Spectroscopic Analysis Of Potential Astromolecules Via Quantum Chemical Quartic Force Fields, Mason Gardner

Honors Theses

Astrochemistry has been substantially aided by computational techniques, particularly through the use of Quartic Force Field (QFF) analysis. Several methods have proven useful at correlating computed spectroscopic data with experimental observations. The F12-TZ QFF correlated well with experimental data for silicon oxide compounds, particularly those potentially involved in development from rocky bodies to planetary masses [27]. Compared to argon matrix experimental data, the vibrational frequencies for the molecules SiO2, SiO3, Si2O3, and Si2O4 become less accurate as the complexity of the molecules increases but should still be predictive of infrared characteristics of silicon oxides as they form clusters in space …

Determination Of Metals In Whey And Vegan Protein Supplements Using Inductively Coupled Plasma Mass Spectrometry, Megan Lofaso

Honors Theses

Driven by a demand for health and wellness products worldwide, the dietary supplement industry continues to expand with an economic impact >$100 billion in the USA alone. However, the industry is plagued by a lack of regulation and incidents of contamination, including with toxic heavy metals that can put consumers at potential risk. In this study, eight trace elements (Cd, Pb, Fe, Co, Mn, V, Cu, and Cr), including heavy metals (Cd and Pb), were determined in whey and vegan protein powder by inductively coupled plasma mass spectrometry (ICP-MS) after microwave-assisted digestion using nitric acid and hydrogen peroxide. Samples were …

Synthesis And Conductivity Analysis Of A Methyl (Polyethylene Glycol) Comb Polymer, Olivia Fox

Honors Theses

The overall goal of work in this field is to improve materials for use in a variety of applications in fuel cell and battery production. This thesis specifically investigates the synthesis of two variations of a methyl (polyethylene glycol) comb polymer electrolyte (MePEG_nwhere n=7) to understand how the molecular structure of an ion-conducting polymer affects its electrochemical properties. The MePEG used in this synthesis contains seven ethylene glycol groups and was added to a poly (methylhydrosiloxane) comb polymer backbone. In the first sample, the polymer contained only the MePEG sidechain, and in the second sample, the polymer contained …

Synthesis Of Halogenated Glyoximes, Nickie Tiwari

Honors Theses

Dr. Huang is a chemical engineering professor at the University of Alabama. He is interested in using alpha-Halogenated glyoximes to better understand impurity incorporation of organic additives. Various alpha-Halogenated glyoximes are being synthesized for his study. In this project, bromodimethylglyoxime is being synthesized. This is a two-step reaction. The first reaction converts diacetlymonoxime to bromodimethylglyoxalmonoxime through bromination. The product is then reacted with hydroxylammonium chloride to form bromodimethylglyoxime. Ultimately, there has been success in forming bromodimethylglyoxalmonoxime. For this reaction, solvent ratios of methanol must be proportional to literature values. However, there have been difficulties in converting bromomonoxime to bromodimethylglyoxime. There …

Preparation Of Perylene Bisimide Acceptors With Ethylcarboxyl And Pyrenylcyclohexyl Imide Groups, Michael Cashen Stark

Honors Theses

Multiple attempts were made to deprotect TBDMS-protected (tert-butyldimethylsilyl protected) serinol and swallowtailed PBI (Compound 2), synthesized by past researcher Tarrah Frederick, to generate Compound 1. The theoretical Compound 1 product is intended for use in molecular rectification of electricity because the perylene core acts as a good acceptor with high electron affinity, and it does not require an electron donor group. Many rectification molecules are amphiphilic Donor-σ-Acceptor compounds, which allow for electron transfer through localized molecular orbitals when placed between electrodes (Langmuir-Blodgett Method). However, PBIs can transfer electrons from one electrode, through the LUMO of perylene, and to the other …

A Spectroscopic And Computational Study Of Diacetyl And Water Clusters, Margaret Baldwin

Honors Theses

Diacetyl, otherwise known as 1,2-butadione or biacetyl, is a flavor additive used in microwave popcorn, and more importantly as of late, e-cigarettes. The compound is known to cause lung disease for those who have been exposed to a large quantity of the buttery smelling molecule. As such, the characterization of diacetyl’s vibrational modes when it interacts with water are pivotal to understanding the effects it has on human lung tissue. In this research, the intermolecular interactions between water and diacetyl and the effects they have on one another’s vibrational modes are explored. While some experimental data is presented, the spectra …

Indolizine Donor-Based Dyes For Applications In Fluorescence Biological Imaging, William Meador

Honors Theses

NIR emissive fluorophores are intensely researched due to their potential to replace modern imaging procedures. Many molecular strategies have been employed in the literature to optimize fluorophores for deeper NIR absorption and emission, biocompatibility, and higher fluorescence quantum yields. Amongst the fluorophores studied to date, proaromatic indolizine donors are attractive alternatives to traditional alkyl amine and indoline based donors due to their 1) lower energy absorption and emission facilitated by proaromaticity, 2) large Stokes shifts due to increased dihedral angles about the π-system, 3) ease of functionalization and capacity for bioconjugation at the phenyl ring, and 4) potential for further …

Enhanced Electrochemical And Light-Driven Co2 Reduction By Incoporating Pendant Functionality In The Second-Coordination Sphere Of Molecular Catalysts, Sayontani Sinha Roy

Electronic Theses and Dissertations

With the increase in global population and rapid industrialization, a gigantic amount of greenhouse gases is being released into the atmosphere each year. The catastrophic effect of these accumulated greenhouse gases is driving global climate change and adversely impacting our ecosystem. Popularizing the traditional renewable energy sources (such as solar and wind energy) can mitigate the problem by cutting down anthropogenic CO2 emissions, which is the major contributor to this global problem. However, the intermittent nature of these energy sources is problematic to reliably power society throughout the year. Therefore, converting CO2 to various value-added chemicals with the aid of …

Application Of Passive Air Samplers For Atmospheric Research, And Determination Of Metals In Tree Rings And Marine Sapropel By Icp-Ms, Byunggwon Jeon

Electronic Theses and Dissertations

This research focuses on studies of atmospheric mercury (Hg) using passive air samplers (PAS) and studies of trace elements in tree cores and sediment using inductively coupled plasma mass spectrometry (ICP-MS). Mercury is a toxic element that is dispersed globally through the atmosphere. Accurately measuring airborne Hg concentrations aids understanding of the pollutant’s sources, distribution, cycling, and trends. Mercury PAS are designed to capture gaseous elemental mercury (GEM) at a known rate. Compared to active air sampling the low-cost of PAS allows for greater spatial coverage. We used a commercially available Hg PAS (MerPAS®) and observed differences in GEM between …

Polyester-Pamam “Janus-Type” Linear-Dendritic Blockopolymers (Ldbcs) As Next Generation Biomaterials, Indika Chandrasiri

Electronic Theses and Dissertations

Nanomedicine is defined as the application of knowledge and tools of nanotechnology for disease treatment, diagnosis, monitoring, delivery, and sensing. Rapid advances in polymer chemistry and nanotechnology have led to an extensive development of polymeric-based therapeutic systems for nanomedical applications. Compared to traditional molecular-based therapies, polymers facilitate a higher level of versatility and functionality, such as simultaneous imaging and delivery. In particular, amphiphilic diblock copolymers and their self-assemblies have shown apparent success in nanomedicine owing to their ability to provide narrow molar mass distributions and highly ordered nanoscale multimolecular aggregates, including micelles and vesicles. However, engineering these polymeric materials to …

Advancements Toward Sustainable Solar Fuel Production Utilizing Reductive Homogeneous Electro- And Photocatalysis, Hunter Pratt Shirley

Electronic Theses and Dissertations

Molecular CO2 and H+ reductive catalysts, whether they be electro- or photocatalytic, have been shown to be possible routes of harnessing solar energy in a clean, renewable manner. There are few electrocatalysts operating at reasonable overpotentials to prove useful in artificial photosynthetic systems, and there are a number of environmental factors within these systems that have yet to be evaluated. Photo-driven catalysis is rare, difficult to control, and rarely provides high-value CO2 reduction products. I report herein an exceptionally low overpotential H+ reduction catalyst, a method of modulating electrocatalysts in-situ to improve performance, a first-of-its-kind mononuclear proton reduction photocatalyst, a …