Chemistry Commons^™

Machine-Learning Classification To Predict The Dimensionality Of Hybrid Organic-Inorganic Halide Perovskites, Yatiwelle Koralalage Samuditha Sandaru Yatiwella

Theses and Dissertations

Low dimensional hybrid perovskites have demonstrated remarkable performance in photovoltaic applications, primarily due to their exceptional optical and electronic properties. As the search for potential candidates for novel materials continues, understanding the structure of these materials is crucial for investigating their stability. In this study, we implement a framework to find novel material based on a machine-learning model. The machine learning model was trained to predict the dimensionality of the polyhedral network based on the connectivity of the polyhedral network in different directions. The polyhedral connectivity of low-dimensional structures can be classified into three dimensions: 0D, 1D, and 2D. This …

Computational Qsar & Molecular Docking Of Anti- Inflammatory Asthma Drugs Against Human Serum Albumin: A Computational Approach Towards Drug Design & Drug Discovery, Sara Alkarimy

Theses and Dissertations

There is a growing need for medications to fight deep-rooted and new diseases because of their socioeconomic consequences, as evidenced by the COVID-19 epidemic which slowed down the economy and affected the social life of mankind globally. This work is a step among many other steps undertaken by research around the world in order to achieve this objective. Asthma is one of the diseases that causes the death of thousands of lives every year. This work aims at the development of novel anti-inflammatory asthma drugs where the quantum chemical descriptors of eleven anti-inflammatory asthma drugs including Ambroxol, Amoxicillin, Budesonide, Fluticasone, …

Atomistic Assessment Of Drug-Phospholipid Interactions Consequent To Cancer Treatment: A Study Of Anthracycline Cardiotoxicity, Yara Elsayed Ahmed

Theses and Dissertations

Despite being one of the most effective chemotherapeutic agents developed to date, Anthracyclines are notorious for their cardiotoxicity. Their clinical use is frequently limited both in dosage and in prescription due to the severe cardiac damage they cause. The mechanism of anthracycline-induced cardiotoxicity is not yet fully understood. However, it is hypothesized that interactions with the myocardial membrane play an important role in imparting cardiotoxicity. In this study, we use molecular dynamics simulations and density functional theory calculations to study the anthracycline drug molecules and the interactions that they have with the myocardial membrane. We construct a myocardial membrane model …

The Effect Of The Carbon Nanotubes’ Surface Area On The Morphology And Performance Of Cellulose Acetate Nanocomposite Membranes In Nanofiltration Applications, Nouran Elbadawi

Theses and Dissertations

Population increase and climate change have significantly affected the availability of fresh water for consumption. Studies by UNESCO showed that more than 28% of the world population didn’t have access to clean safe drinking water in 2020. This situation is expected to get more serious over the coming 30 years with the limited availability of natural fresh water sources. The need to find solutions from alternative non-freshwater resources for drinking or irrigation is becoming a necessity. Within the context of desalination technologies, thousands of investigations are conducted to find the cheapest most efficient way of water treatment aiming at expanding …

Catecholamine System Function Of The Medial Prefrontal Cortex Following Repetitive Mild Traumatic Brain Injury And The Use Of Benzoyl Chloride To Quantify And Identify Neurotransmitters, Leah Horvat

Theses and Dissertations

Traumatic brain injury (TBI) is a serious global health burden that causes a wide range of neurocognitive symptoms. These cognitive processes are regulated by catecholamine signaling within the prefrontal cortex (PFC) region of the brain. To quantify functional deficits in catecholamine signaling after TBI, norepinephrine (NE) and dopamine (DA) levels within the PFC were quantified from microdialysate samples using high-performance liquid chromatography coupled with electrochemical detection. A method for benzoyl chloride derivatization of neurotransmitters and analysis with liquid chromatography and tandem mass spectrometry instrumentation was also developed to detect and analyze these neurotransmitters. Overall, it was found that catecholamine signaling …

Ionic Nanomaterials And Doped Carbon Materials: Synthesis, Characterization, And Application In Cancer, Energy, And Environment, Samantha Paige Macchi

Theses and Dissertations

Materials is a crucial area of science which encompasses the design, synthesis, and application of various chemicals or other materials. Determining the relationship between materials’ physical, chemical, and photophysical properties on their performance is crucial to design the most optimal materials. This dissertation is focused on two types of materials: ionic liquids and heteroatom doped carbons as well as their various applications. Part A of this dissertation is focused on the development of various frozen ionic liquids (ionic materials, IMs) and nanoparticles derived from IMs as cancer therapeutics. The effect of various counterions on the photophysical and cytotoxic properties of …

Biopolymer-Coated Magnetite Nanoparticles For The Removal Of Emerging Contaminants From Aqueous Solutions, Hebatullah Farghal

Theses and Dissertations

Abstract

Biopolymers are gaining interest as promising materials for water purification due to their functionality, biodegradability, abundance, and safe use. In this work, three biopolymer-based systems were developed as adsorbents for removing emerging contaminants from water. The first system of biopolymeric nanocomposites was synthesized by coating chitosan/xylan biopolymeric nanocomposites on magnetite nanoparticles (CsXM) to facilitate their separation from water via a magnetic field. The prepared mesoporous CsXM nanocomposite was thermally stable and possessed a particle size of 11 nm and a neutral to slightly negative charge over the studied pH range of about 3 to 10. The nanocomposite efficiently removed …

Artemisinin And Its Derivatives Reactions: Characterization Of The Reaction Products Using Lc/Tof Ms, Kogila Vijayan

Theses and Dissertations

Artemisinin (ART) is a sesquiterpene lactone and a popular malaria drug with potential anticancer properties. In this work, LC/TOF MS was used to investigate the reaction of ART with DNA bases and estradiol. ART-deoxyadenosine and ART-deoxycytidine interactions were studied in the presence of Fe (II) ions. ART-deoxyadenosine and ART-deoxycytidine reaction mixtures gave chromatographic signatures that remained unchanged at room temperature but grew after incubation at 37°C. The change in temperature from room temperature to 37°C was the main driver of adduct formation in these reactions. ART was found to react with Fe (II) ions as observed from several new chromatographic …

Computational Study Of Foldamer-Based Water Channels, Shadi Houshyar Azar

Theses and Dissertations

One of the most serious global challenges of this century is water scarcity, stemming primarily from the growing demand for freshwater and the depletion of freshwater resources. Water desalination has the potential to address this problem, but current technologies are expensive and inadequate. Here, we present novel, computationally designed channels with high water permeability and selectivity against ions, inspired by natural water channels, aquaporins. Aquaporin's unique property of transporting water while rejecting protons and other ions has led to numerous studies on incorporating such channels into different membranes for water purification applications. However, use of an aquaporin-incorporated membrane is limited …

Development Of New Chemical Probes To Delineate The Polyamine Regulation & Molecular Strategies To Unravel Protein Polyamination, Vennela Tulluri

Theses and Dissertations

Polyamines such as putrescine, spermidine, and spermine modulate critical cellular processes, including gene expression and cell proliferation. Cellular polyamine regulation is a complex mechanism controlled by three different proteins: Ornithine decarboxylase (ODC), Antizyme (OAZ), and Antizyme Inhibitor (AZIN). While ODC is directly involved in polyamine biosynthesis, OAZ, and AZIN regulate the ODC activity via protein-protein interactions. The dysregulation of ODC, OAZ, and AZIN leads to elevated polyamines in numerous pathologies, making them attractive targets for controlling polyamine levels. Besides regulating polyamine synthesis, OAZ modulates polyamine transport. However, the precise mechanism remains elusive. In this research, we discuss our approach to …

Natural Amino Acid Derived Iron (Iii) Catalysts For Green Oxidation Chemistry Applications, Karie Sanford

Theses and Dissertations

Tetraamido macrocyclic ligand activators are a group of catalysts that have been developed to perform green oxidation chemistries. In this thesis, the traditional synthesis of these catalysts was successfully altered to begin with natural amino acids, rather than the conventionally used synthetic derivatives of amino acids, which has never been shown in previous research. This was confirmed using a variety of characterization techniques including electrospray ionization-mass spectrometry. One of these catalysts was utilized in several dye degradation studies, where it was determined that the catalyst can remove about 98% of methylene blue and indigo carmine pollutants from water within 45 …

Halide Substitution Of Ternary Bismuth Chalcogenides For Photovoltaic Applications, Thomas Boggess

Theses and Dissertations

Semiconductors play an integral part in modern society. From computing to LEDs their use is ubiquitous, and no field is more reliant on them than that of power generation. Current political movements have seen a push to decrease reliance on traditional forms of power generation, which relies on fossil fuels, to renewable sources such as solar power. However, current commercial solar panels, based on silicon, are lacking in efficiency, only reaching between 18% and 22% efficiency.¹ In recent years, materials called perovskites have been garnering significant attention as possible replacements for silicon cells due to their favorable optoelectronic properties. …

Microwave-Assisted Depolymerization Of Poly (Ethylene Terephthalate) Via Ethanolysis, Mayra Alejandra Gomez Cortez

Theses and Dissertations

In the search of providing an alternative form of combating the complex environmental concerns rising from the rapid growth of poly (ethylene terephthalate) waste in the world, this research focused on investigating the chemical recycling of PET via ethanolysis. Parameters such as temperature, reaction time, catalyst usage and concentration were investigated to promote depolymerization.

In this work, ethanolysis of waste PET under microwave irradiation was investigated using organocatalysts 1,5,7-Triazabicyclo [4.4.0] dec5-ene (TBD) and 1,8-Diazabicyclo [5.4.0] underc-7-ene (DBU). We evaluated the effectiveness of reaction conditions through a series of experiments and determined the optimum conditions as follows: 0.5 g of PET, …

Design And Synthesis Of Novel Peptide-Metal Organic Frameworks, Moustafa Mahmoud Abdel Wahid Hamaad

Theses and Dissertations

Metal-organic frameworks (MOFs) are a class of crystalline porous materials with extended network structures formed through the reticular assembly of inorganic and organic molecular building blocks through strong coordination bonds. Compared to other porous materials, MOFs offer a high degree of structural diversity as their shape and pore size as well as functionality can tuned by the precise selection and design of their metal centers and organic struts. Due to their high surface areas, pore volumes, and the possibility of introduction of a myriad of chemical functionalities in their structures, MOFs have gained popularity for applications in many fields such …

Anti-Doping Crisis In Sports, What's Next? Ion Mobility-Mass Spectrometry For The Study Of Anabolic Androgenic Steroids, Diana Constanza Velosa

Theses and Dissertations

The main objective of this work is to augment both qualitative and quantitative measures of anabolic androgenic steroids (AAS) with ion mobility-mass spectrometry (IM-MS), laying the foundation for implementation into analytical drug testing laboratories. AAS testing requires high sensitivity and specificity. IM-MS is presented as an emerging technology workflow capable of targeted quantification of AAS and structural elucidation for potential unknowns, allowing ions to be separated and characterized based on their rotationally averaged collision cross section (CCS). Chapter 1 provides a background of the basic principles of IMS and the different types of analytical methods used for doping analysis currently …

Analysis Of Steroid Hormone Isomers Using Ion Mobility-Mass Spectrometry, Shon Paul Neal

Theses and Dissertations

This dissertation presents a comprehensive study on the analysis of steroid hormone isomers using liquid chromatography-ion mobility-mass spectrometry (LC-IM-MS). The dissertation is divided into three main parts: the first part focuses on research using different drift gases and ion adducts to modify the mobility separations allowing for resolution between the isomers. The second part focuses on research exploring derivatization reactions that target structural differences between the steroid hormone isomers to amplify the differences and resolve the isomers in the ion mobility region. The final part covers a proposal on future study directions to include simultaneous derivatization reactions, mass spectrometry fragmentation, …

1. Influence Of Metal Ions And Solvents On The Photo-Generation Of Reactive Oxygen Species In Mesoporous Silicate Embedded Porphyrins 2.Water-Soluble Rhodium(Iii) Porphyrin Complex For The Biological Inactivation Of Fentanyl, Hemant Pal

Theses and Dissertations

Porphyrins are differentiated π-conjugated compounds with unique photochemical and redox properties. The tetrapyrrole macrocycle core of porphyrins is extremely favorable for the complexation of metal ions, resulting in hybrid metal-organic molecules with good catalytic properties. Porphyrin-based systems are known for their oxidative properties and are frequently utilized as bio-mimicking catalysts and environmental remediation agents. My current research aims at both of these aspects. One of the most efficient methods to create photocatalytic systems with outstanding features and applicability is the use of porphyrins on supported solid materials. A series of novel mesoporous silicate-embedded metalloporphyrins were prepared via conjugation of novel …

Water-Soluble Iron Porphyrin Complex For The Catalytic N-Dealkylation Of Fentanyl, Amanda Pitt

Theses and Dissertations

An increase in the misuse of opioids in the United States and the increasing potency of analogs necessitates novel treatments of opioid overdose. The chemical structure of synthetic opioids, such as fentanyl, carfentanil, and morphine possess a trialkyl amine functional group (-NR3) which makes for a promising target for potential catalysts. Iron (III)-tetrasulfonatophenyl porphyrin (complex 9) was synthesized as a potential catalyst for degradation of fentanyl. Complex 9a was prepared from the direct reaction of the free porphyrin and FeSO4. Complex 9b was prepared from the direct reaction of the free porphyrin and FeCl2 in refluxing DMF. The complexes were …

Bacterial-Mediated Photocatalytic Organic Oxidation, Peter J. Pellegrinelli

Theses and Dissertations

Bacteria, though well-known and widespread in scientific application, have plenty more opportunity to grow in the field of organic synthesis. The primary objective of this project was to apply the use of bioluminescent bacteria in an organic photoredox reaction intending to use the bacteria as a renewable source of light. This sustainable method, as opposed to high wattage bulbs, paves a green pathway for organic photocatalytic reactions. Using bioluminescent E. coli, the focus was on performing organic oxidation reactions with a recyclable photocatalyst. When using bacteria in conjunction with chemicals like nitromethane, it was an obstacle to keep the E. …

Evaluation Of A Radium-Thorium Disequilibrium Sediment Method Used To Model And Assess Porewater And Submarine Groundwater Exchange In The Coastal Marsh, Madeline R. Bodine

Theses and Dissertations

Ground, pore, and surface water exchange has been extensively studied in beach and near shore environments but has been long neglected in saltmarsh systems due to their complexity. Saltmarsh systems are of particular importance as they are the interface between fresh and saltwater. Saltmarshes impact carbon exchange, release and sequestration, and they process particulate matter. Understanding the characteristics of a marsh system such as the nutrient and particulate loads in conjunction with the flux of water exchange through the marsh provides a deeper understanding of these systems and can impact our understanding of the global water and carbon cycles, as …

Surface And Alloy Engineering Of Halide Perovskite (Cspbx3) Nanocrystals For Efficient And Stable Optoelectronics, Sakiru L. Abiodun

Theses and Dissertations

Organic and inorganic halide perovskite quantum dots (QDs) (in form of ABX₃, where A is organic cation e.g CH₃NH₃⁺ or inorganic cation e.g Cs⁺) have emerged as an intriguing alternative to the widely studied chalcogenide and pnictide QDs. Their excellent optoelectronic properties such as large absorption coefficient, high carrier mobility, wide color gamut, long electron-hole diffusion lengths, and tunable bandgap energy are largely responsible for their wide acceptability in various electronic devices. However, despite this enthusiasm, the problem of purification, long-term stability, lead toxicity and inadequate knowledge of their surface chemistry still …

Engineering Of Bio-Based And Synthetic Polymers: Synthesis And Application In Superabsorbent Materials And Antibacterial Agents, Jihyeon Hwang

Theses and Dissertations

A polymer consists of a large number of monomer units, which can be obtained naturally or via a chemical process called polymerization. Polymers are important materials that are used in our daily life. Life would not be possible without these polymers, either from plant biomass or petroleum-derived synthetic polymers. The substitution of petroleum-derived to biomass-based polymers has been highlighted to mitigate adverse environmental impact. However, the use of bio-based polymers is still a significant challenge for more demanding applications. In this dissertation work, the engineering of both bio-based and synthetic polymers and their properties are investigated.

In Chapter 1, the …

Structural And Immunological Characterization Of Inhaled Allergens And Their Complexes With Antibodies, Kriti Khatri

Theses and Dissertations

Allergy is an outcome of an allergen-antibody reaction (1). Potent airborne allergens from dust mites and pets are major causative factors for allergic conditions among predisposed individuals. Group-2 allergen Der p 2 from Dermatophagoides pteronyssinus is a major allergen which causes allergic conditions in more than 80% of mite-allergic subjects (2). Similarly, airborne allergen Can f 1 from dog (Canis familiaris) is also a major risk allergen which affects 10-20% of the population worldwide (3). Considering the increasing prevalence of inhalant allergens in the environment, antigenic characterization is crucial for improving allergy diagnostics and management. This study focuses …

Vaccinia Virus And Measles Virus As Oncolytic Vaccines: The Modulation Of The Viral Infectivity Via Surface Conjugations, Monchupa Kingsak

Theses and Dissertations

Oncolytic virus (OV) therapy has been shown to be an effective targeted cancer therapy treatment in recent years, providing an avenue of treatment that poses no damage to surrounding healthy tissues. Not only do OVs cause direct oncolysis, but they also amplify both innate and adaptive immune responses generating long-term antitumor immunity. However, a key challenge facing oncolytic virotherapy is neutralizing antibodies in vaccinated patients, leading to the viral clearance after systemic administration and failure in the treatment. The encapsulation of OVs using biocompatible polymers is one of the promising methods to prevent the viral clearance from antiviral immune responses. …

The Kinetic Control Of Polymer Micelles; Chemical Functionality, Material Interactions, And Equilibration, Taylor Larison

Theses and Dissertations

Polymer micelles have found significant uses in areas such as, energy storage devices, catalysis, opto-electronics, drug-delivery, oil additives, and nanoreactors. In many of these applications the overall micelle size (aggregation number) and chemical functionalization determines performance. To progress towards more advanced materials synthesized from the facile bottom-up approach with polymeric micelles the implementation and study of thermodynamic handles were investigated. Here the kinetic control of micelles was studied across a range of applications; independent control over micelle functionality, the spatial orientation of multiple metal oxide nanoparticles in mesoporous materials via self-assembly, and the use of small-angle neutron scattering (SANS) to …

Coordination Environment And Thermodynamics Of Colloidal Quantum Dots In Polar Solvents, Nuwanthaka Prasad Jayaweera Millaniyage

Theses and Dissertations

Colloidal semiconductor quantum dots (QDs) have been extensively investigated due to their attractive properties such as size-tunable absorption and emission spectra, large molar extinction coefficients, and significant photostability. These properties make them promising candidates for optoelectronic, photocatalytic, and biomedical applications. Common synthetic procedures of QDs produce nanocrystals capped with long-chain fatty acid derivatives which are stabilized in high boiling point solvents. Especially for bioimaging applications, the exchange of these native hydrophobic ligands with hydrophilic ligands should be performed, while preserving the smaller hydrodynamic radius. The coordination environment and thermodynamic parameters of the ligand exchanges should be carefully investigated to engineer …

Biochemical, Structural, And Immunological Characterization Of Selected Panallergens, Andrea Leigh O'Malley

Theses and Dissertations

Allergies throughout the world are increasing in prevalence and severity. Although the direct causes of the development of allergies are not confirmed, study of proteins that cause reactions will lead to a deeper understanding of allergy. This work focuses on three panallergen families, profilins, parvalbumins, and arginine kinases, to further elucidate the background of allergy from the point of view of the allergens themselves. In Chapter 1, we evaluate pollen, fruit, and mite profilins in the context of allergy, showing the relevance of conserved cysteine residues in stability and oligomerization as well as the first data on cross-reactivity between plant …

Reactive End Capped Polybenzimidazole Oligomers For High Temperature Thermosets And Improved Membranes For Electrochemical Devices, Caroline Marie Rohlfing

Theses and Dissertations

Polybenzimidazoles (PBI) are heterocyclic polymers that possess high thermal and oxidative stability. The inherent strength and chemical and thermal stability of PBI make it ideal for use in extreme environments; however, the current processing of PBI molded parts makes the process practically and economically unfavorable. These intrinsic properties make PBIs of particular interest for many industrial applications, varying from fabrics to membrane materials to molded parts. Processing these molded parts is extremely difficult, as the high glass transition temperature and extremely high melting point (>500°C) of PBI result in poor flow properties of PBI resins even at high temperatures. …

Expanding Tailorable Nanomaterial Synthesis With Persistent Micelle Templates, Eric R. Williams

Theses and Dissertations

The control of block polymer micelle dimensions while in solution is critical for a range of emerging applications in diverse fields from drug delivery and nanoreactors to use as sacrificial templates for porous nanomaterials. When under kinetic control, micelles will maintain a constant average size and thus aggregation number (N_agg) through the suppression of chain exchange mechanisms. Such kinetic control effectively enables the decoupling of micelle dimensions from solution conditions. In other words, kinetically trapped micelles can resist reorganizations brough about by e.g., the addition of metal nanoparticles. However, such micelles are traditionally governed by a fickle �� …

Sustainable Approaches To Photo-, Thermo-, And Electro-Chemical Reactions Of Amines, James David Sitter

Theses and Dissertations

In recent years, sustainable routes for chemical synthesis have garnered renewed interest. As the world continues to fight pollution and rising costs, it is imperative that new routes of synthesis that continuously fight the issues of pollution and waste are discovered, defined and explored. While traditional synthesis routes that require energy input typically require the burning of fossil fuels to produce heat, the amount of resources that go into the production of these fossil fuels and the sequestration of its waste to minimize its impact on the carbon footprint is enormous. Furthermore, sustainable chemistry research aims to decrease and minimize …