Chemistry Commons^™

Synthesis And Characterization Of Starburst Pseudorotaxanes And Their Metallic Derivatives, Shalini D. Kadinappulige

Masters Theses

Mechanically Interlocked Molecules (MIMs) are interlocked molecular architectures, characterized by the fact that they are linked through a mechanical bond. Catenanes, rotaxanes, molecular knots, and Borromean rings are typical examples for these molecules. Since MIMs are not connected by covalent bonds, hydrogen bonding, π- π stacking, and/or electrostatic interactions help bring the components together. Dialkyl-ammonium centers, bis(pyridinium)ethane dications, viologen species, and naphthalenediimide π-deficient groups are well known as recognition motifs for crown ethers. In the research described here, we have synthesized several pseudorotaxanes and their tricyclohexyltin metallic derivatives, based on benzobis(imidazolium) (BBI) salts as axles, in combination with the 15DN38C10 …

Development Of Supported Pd-Based Catalysts For Carbon-Carbon Cross-Coupling And Oxidation Reactions, Mrinmoy Das

Theses and Dissertations

Heterogeneous catalysts are a crucial part of chemistry used for various chemical synthesis stages, pharmaceutical, and environmental applications. The use of nanoparticles or rather nanocatalysts enhances the heterogeneous catalytic applications. Both chemical and physical methods can be used to synthesize nanocatalysts. Chemical synthesis methods require comparatively fewer instruments and can easily synthesize a large amount of nanocatalysts. Nevertheless, chemical synthesis methods require reducing agents and solvents that can be toxic or harmful materials. They often need harsh reaction conditions as well, like high temperature and pressure. On the other hand, physical synthesis methods often require complex instrument setup, but their …

Discerning The Spectroscopic Properties And Chemical Reactivity Of Bioinspired Metallocomplexes, Ashley K. Forney

Theses and Dissertations

In Nature, metalloenzymes catalyze a variety of thermodynamically demanding reactions with remarkable performance under mild, physiological conditions. This innate ability is a driving force for the development of nature inspired, synthetic analogues that are robust and can catalyze a variety of organic transformations. This work involves the successful syntheses of four coordinate, bioinspired complexes, [M^II(n-DOB)] (M = Ni, Co, and Cu; n = 12 and 13), which have been characterized by NMR, ESI-MS, UV/Vis, EPR, and CV. Spectroscopic evidence presents the generation of reactive metal-(di)oxygen species that display amphoteric reaction behavior, making these rarities among inorganic oxidants. These …

Detection Of Biomolecules Via Ocp Measurements Using Npg Electrodes, Borkat Ullah

Theses and Dissertations

In sensing application nanoporous gold (NPG) has attracted much attention. NPG is prepared by dealloying Au:Ag alloys. Characterization was done using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV). In this work, the open circuit potential (OCP) of ferricyanide, cysteine, uric acid, and ascorbic acid was measured in phosphate buffer solution (PBS) and biofouling solution containing bovine serum albumin (BSA) at pH 7.4. OCP measurement has been hindered due to biofouling and surface passivation on the metal electrodes. By the use of the NPG electrodes, electrochemical activity can be maintained. From the OCP measurement of cysteine, …

Redox-Active Porous Organic Materials For Electrochemical Energy Storage Applications, K. Shamara Weeraratne

Theses and Dissertations

As the demand for renewable energy technologies grows, so does the need for cheaper, more efficient rechargeable batteries to store the energy. While lithium-ion battery (LIBs) technology is well established, it suffers from limited lithium supplies. Furthermore, the highly toxic transition metals used in the electrodes places a huge burden on the environment. Therefore, replacing lithium with more economical sodium metal in rechargeable batteries (i.e. sodium-ion batteries, SIBs) has garnered considerable attention. Despite the fact that sodium and lithium share similar electrochemical properties, which may cause the transition from lithium to sodium easier, the larger ionic radius of Na^{+ …}

Solid Phase Extraction And High-Precision Mass Spectrometry Analysis Methods For Crassostrea Virginica Metabolome, Alyssa Darling

Theses and Dissertations

Metabolomics is the rapidly-growing field which focuses on the endpoints of biological processes, and has the capability to provide a snapshot of an organisms’ interaction with their environment on a molecular scale. The objective of the experiment herein was to develop a standard metabolic extraction technique coupled with ultrahigh-precision analytical tools to build a global metabolic pathway of the keystone species Crassostrea virginica. To achieve this, C. virginica whole-body samples were extracted using acetonitrile and methanol, then split into a dehydrated group and a diluted group. Following reversed-phase solid phase extraction (RP-SPE) of both groups, metabolites were identified using …

Solvolytic Lignocellulosic Biomass Liquefaction, Mustafa Alluhaibi

Electronic Theses and Dissertations

Increasing energy demand, petroleum prices, global warming, and depleting fossil fuel resources are the main challenges faced by the human beings. Many scientists are searching for sustainable and alternative sources of fossil fuels as solutions to these challenges. Lignocellulosic biomass is one of the renewable and eco-friendly abundant sources that has been considered by both academia and industry sectors as a renewable source for bio-oil and chemicals. Direct liquefaction of biomass in the sub-/super-critical solvent has considered a practical method to convert lignocellulosic material into liquid fuel. However, undesirable properties such as poor stability, low energy value, and high acidity …

Characterization Of Naturally Derived Polymer By Oxidative, Thermal, And Spectrometric Methods, Ranen Roy

Electronic Theses and Dissertations

Extensive use of fossil fuel for different purposes has resulted in significant depletion of it at an alarming rate. Therefore, a potential and sustainable alternative source are badly needed at this moment. Nowadays, lignocellulose biomass is appealing to much interest by the researchers because of its potential nature as a renewable carbon source. It is the most abundant renewable source which is composed of cellulose, hemicellulose, and lignin. Among them, lignin is considered the 2nd most abundantly natural polymer after cellulose which comprises 10-30 % of biomass depending on the source and the environment. Lignin is a three-dimensional cross-linked organic …

Antidiabetic Activity Of Cissus Rotundifolia Plant Growing In Saudi Arabia, Saad Ali Alshehri

Electronic Theses and Dissertations

Diabetes mellitus (DM) is a metabolic disease characterized by high levels of blood glucose resulting from defects in insulin production or action. A world-wide increase in the diabetes rate is projected to reach pandemic levels over the next 10-20 years. Current data shows that high numbers of the population in Saudi Arabia suffer from diabetes and prediabetes. Non-traditional treatments of diabetes from medicinal plants has shown potential antidiabetic activity. A considerable percentage of the population still prefer or use medicinal plants as a treatment or supplement to traditional medicine. Cissus rotundifolia (family Vitaceae) is a known plant in southwestern Saudi …

Implementing And Assessing The Use Of A New Strategy For Training Chemistry Graduate Teaching Assistants, Amanda Hyett

Electronic Theses and Dissertations

Graduate teaching assistants (GTAs) largely contribute to undergraduate education but are often underprepared for their role as educators. Most graduate students attend graduate school to perform research and are then asked to teach for the first time without sufficient pedagogy training. To assist in increasing the GTAs pedagogical knowledge, a scenario-based activity series was developed and implemented for first- and second-year GTAs. Developing scenario-based scenarios from actual laboratory events provided GTAs with the opportunity to practice prior to engaging in the laboratory classroom. The Teaching Assistant Intervention Activities (TAIAs) included topics such as interpersonal skills and behaviors, group process, working …

Scavenger Hunt: The Search For Sulfur Mustard-Neutralizing Compound In 2-Chloroethyl Ethyl Sulfide (Cees) Treated Human Keratinocyte (Hacat) Epithelial Cells, Tanner Diemer

Electronic Theses and Dissertations

Sulfur mustard is a highly toxic and dangerous vesicant that has been utilized as a chemical warfare agent (CWA) since World War I. Despite its extensive history, an effective antidote to sulfur mustard exposure still does not exist. With detectable levels of unreacted sulfur mustard lasting days after initial contact, a window of opportunity exists to administer a “scavenger” to affected individual immediately and in the days following exposure in hopes of reducing harm by neutralizing unreacted sulfur mustard. For this strategy to be effectively implemented, it is essential to identify a candidate compound with excellent affinity towards sulfur mustard …

The Characterization And Reactivity Of Tris(4-Methylpyrazolyl)Methane And Its Tungsten And Molybdenum Metal Complexes, Julia M. Pomeroy

Undergraduate Honors Thesis Collection

The scorpionate ligand tris(pyrazolyl)borate (Tp) has contributed to the understanding of coordination and organometallic chemistry and has proven to be useful in the synthesis of metalloprotein models. Studies focusing on the similar ligand, tris(pyrazolyl)methane (Tpm), have recently been made possible with improved synthetic techniques. Characterization of the Tpm ligand and its metal derivatives, [TpmW(CO)3L]+ and [TpmMo(CO)3L]+, unveiled unexpected activity in the 1H NMR chemical shift of the methane hydrogen after the coordination of a seventh ligand. The more electronegative the seventh ligand was, the more downfield the chemical shift appeared. Various analogs of Tpm have since been synthesized that substitute …

Non-Canonical Targets, Reaction Kinetics, And Cellular Potency Of Amino Acid-Linked Platinum(Ii) Compounds, Bett Kimutai

Wayne State University Dissertations

DNA serve as an ideal target where drugs such as cisplatin (cisPt) bind and exert their anticancer activities. CisPt is known to preferentially coordinate with DNA leading to formation of cisPt-deoxyguanosine (dGuo) adducts. The adducts distort the DNA structure and contribute to inhibition of DNA-mediated cellular functions and ultimately cancer cell death. Despite its utilization as an anticancer drug, cisPt has a number of drawbacks, which include toxic side effects and cellular resistance. Resistance occurs through processes such as repair of damaged DNA and inactivation of cisPt present in the cell. To overcome these challenges, the aim of this thesis …

Singlet Oxygen Generation By Porphyrins And Metalloporphyrins Revisited: A Quantitative Structure-Property Relationship (Qspr) Study, Andrey A. Buglak, Mikhail Filatov, Althaf M. Hussain, Manabu Sugimoto

Books/Book chapters

state followed by formation of singlet oxygen (1O2), which is a highly reactive species and mediates various oxidative processes. The design of advanced sensitizers based on porphyrin compounds have attracted significant attention in recent years. However, it is still difficult to predict the efficiency of singlet oxygen generation for a given structure. Our goal was to develop a quantitative structure-property relationship (QSPR) model for the fast virtual screening and prediction of singlet oxygen quantum yields for pophyrins and metalloporphyrins. We performed QSPR analysis of a dataset containing 32 compounds, including various porphyrins and their analogues (chlorins and bacteriochlorins). Quantum-chemical descriptors …

Enhanced Covalent Interface, Crosslinked Network And Gas Barrier Property Of Functionalized Graphene Oxide/Styrene-Butadiene Rubber Composites Triggered By Thiol-Ene Click Reaction, Long Zheng, Stephen Jerrams, Tian Su, Zongchao Xu, Liqun Zhang, Li Liu, Shipeng Wen

Articles

The high gas barrier property of a rubber composite is of great significance for reducing the exhaust gas emissions due to tire rolling resistance and hence the contribution this factor makes to environmental protection. Enhanced covalent interfaces and crosslinked networks are crucial to the gas barrier property of rubber composites. In this research, γ-mercaptopropyltriethoxysilane (MPS) modified GO (MGO)/styrene-butadiene rubber (SBR) composites were prepared by a synergetic strategy of latex compounding method and thiol-ene click reaction. It was found that the mercapto groups in MGO reacted with the vinyl groups in SBR molecules through thiol-ene click reaction during the crosslinking process …

Β-Methylumbelliferone Surface Modification And Permeability Investigations At Pentel™ Graphite Electrodes, Susan Warren, Brian Seddon, Ruth Pilkington, Alison Crossely, Philip Holdway, Eithne Dempsey

Articles

Electrochemical and micro-imaging analysis of a commercial graphite-composite material is presented following electro-oxidation with β-methylumbelliferone. Charge-transfer surface modification was observed for the graphite electrode, presumed to have arisen from adsorbed interfacial umbelliferone moieties. The molecular permeability of the new surface towards a range of similar, yet size-variable (23 Å3–136 Å3) molecular redox probes is discussed. Red-shift fluorescence in confocal microscopy offers further support for the presence of a surface-bound umbelliferone layer. An SEM-platinum profiling technique was used as an imaging tool to map the umbelliferone surface and size-distribution of electroactive sites.

K-Means And Hierarchical Cluster Analysis As Segmentation Algorithms Of Ftir Hyperspectral Images Collected From Cutaneous Tissue, Cassio Lima, Luciana Correa, Hugh Byrne, Denise Zezell

Conference papers

Fourier Transform Infrared (FTIR) spectroscopy is a rapid and label-free analytical technique whose potential as a diagnostic tool has been well demonstrated. The combination of spectroscopy and microscopy technologies enable wide-field scanning of a sample, providing a hyperspectral image with tens of thousands of spectra in a few minutes. In order to increase the information content of FTIR images, different clustering algorithms have been proposed as segmentation methods. However, systematic comparative tests of these techniques are still missing. Thus, the present paper aims to compare the ability of K-means Cluster Analysis (KMCA) and Hierarchical Cluster Analysis (HCA) as clustering algorithms …

Diclofenac Determination Using Ceo2 Nanoparticle Modified Screen-Printed Electrodes:A Study Of Background Correction, Rafaela C. De Carvalho, Tony Betts, John Cassidy

Articles

The detection of low levels of drugs including Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) in natural waters and wastewaters is becoming increasingly important. Electrochemical methods offer an attractive means of detection, as they overcome many disadvantages associated with the currently available analytical methods. Cerium dioxide nanoparticles were synthesised and then incorporated onto the working electrodes of commercial graphite-based Screen Printed Carbon Electrodes (SPCE) then used to determine diclofenac levels. Following initial Cyclic Voltammetry studies, Square Wave Voltammetry (SWV) investigations were conducted over a range of conditions to optimise the peak potential separation and sensitivity of the method. The use of background correction …

Lew,1wr1 Rat Shows An Increased Risk Of Developing Malignant Forms Of Nafld, Luis Mercado

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

A Comparative Study Of Drug Affinities Determined By Thermofluor And Kinetic Analysis, Oruba Shatnawi

Theses, Dissertations and Culminating Projects

Determining the binding affinity and potency in vitro is one of the significant steps that can give a clue for a new candidate drug during the drug discovery process. Thermofluor is a method used in measuring binding affinity (Kd) of protein-ligands interaction through determining the change in thermal denaturation temperature of protein using real time PCR (RT-PCR). Kinetic analysis assay is used to screen a library of compounds to calculate their potencies (IC50) and inhibition constants (Ki) and it can be performed by spectrophotometer technique. In this study, we used bovine carbonic anhydrase II (BCA II) enzyme, and four of …

Preparation And Crystal Structures Of Racemic And Quasiracemic Imidazole Or N-Methyl Imidazole Copper Complexes Containing Substituted N-Benzoylalanines, Emily Catherine Chong

Theses, Dissertations and Culminating Projects

A quasiracemate is the cocrystallization of two similarly shaped but chemically distinct molecules of opposite handedness. There has been limited to no work regarding quasiracemates in the field of inorganic chemistry. The goal of this study was to prepare various metal based enantiomers, racemates, and quasiracemates using N-benzoylalanines with imidazole or N-methylimidazole as ligands bound to copper to form a metal complex. In this study, we developed a method to prepare substituted N-benzoylalanines and its copper complexes. We also prepared one co-crystal between two differently substituted N-benzoylalanines.

This work reports the successful synthesis and crystal structure analysis of an organic …

Understanding The Rage Signaling Pathway And Its Contribution To Diabetic Complications, Leon Vegas Ho

Legacy Theses & Dissertations (2009 - 2024)

The binding of advanced glycation end products (AGEs) to the receptor for advanced glycation end products (RAGE) is an important feature of the RAGE signaling pathway that plays a role in the pathogenesis of diabetes. Under high glucose concentration, RAGE expression increases immensely from the formation of a Schiff base by glucose bounded to lysine. This triggers an inflammatory and immune response and upregulates the expression of RAGE and causes an accumulation of AGEs in the body. As a result, this leads to the development of diabetes and other complications such as, atherosclerosis, nephrothapy, and retinopathy. To remedy AGE accumulation, …

Novel Substrate-Free Cholinesterase Based Sensing Of Organophosphorus Compounds, Hailey J. Marini

Legacy Theses & Dissertations (2009 - 2024)

The increasing concerns of chemical weapons used by terrorists is growing, creating a need for infield detection methods that can rapidly detect these compounds that are a major health concern for civilians and military personnel. Displacement is a novel concept for the detection of cholinesterase inhibitors, including organophosphorus compounds, that could replace the classical instrumentation methods currently being used for diagnostics.

Cholinesterase Based System For Fentanyl Detection, Alyssa Shoemaker

Legacy Theses & Dissertations (2009 - 2024)

Opioids and other illicit drugs have become a very prevalent problem across the world, especially in the United States. In fact, every day more than 130 people die from an opioid overdose. Despite many public warnings explaining the risks of opioid and drug use, the epidemic has continued to grow. As illicit drugs are becoming more rampant in society, law enforcement officers need a reliable, rapid, and non-invasive method to detects when someone may be on drugs, for example while driving, and to assess unknown powders or substances when presented at a crime scene containing drugs. Currently, at traffic stops …

Stepwise Reduction Of Non-Planar Molecular Nanocarbons : From Functionalized Bowls To Helicenes And Nanohoops, Zheng Zhou

Legacy Theses & Dissertations (2009 - 2024)

Molecular nanocarbons, which can be considered as fragments of fullerenes, carbon nanotubes, or graphene, have stimulated the rapid development of carbon chemistry at the molecular level in recent decades. Molecular nanocarbons possess not only outstanding chemical and physical properties stemming from their parent carbon allotropes, but also present such unique features as controllable and scalable synthetic conditions, defined molecular compositions, uniform size, and relatively good solubility. These advances of molecular nanocarbons over conventional carbonaceous materials give rise to the development of such applications as electron transfer, energy transport and storage. However, future progress of these technologically-important fields requires a superior …

Identification And Analysis Of Body Fluid Traces For Forensic Purposes Using Vibrational Spectroscopy And Chemometrics, Ewelina M. Mistek-Morabito

Legacy Theses & Dissertations (2009 - 2024)

Recent years have seen a large expansion in the forensic field due to the introduction of novel analytical techniques. Body fluids are an extremely important type of evidence at crime scenes and the main source of DNA. Most current methods for the identification and examination of body fluid traces require chemical treatment and are therefore destructive to the sample. Thus, new methods that are nondestructive and provide rapid results with statistical confidence are desirable. Such methods could eliminate noninformative traces and allow investigators to focus on more valuable pieces of evidence. The ultimate goal of this research is to develop …

Ozone And Reactive Oxidized Nitrogen Chemistry In The Northeast U.S, Matthew Ninneman

Legacy Theses & Dissertations (2009 - 2024)

Ongoing reductions in oxides of nitrogen concentrations ([NOx] = nitric oxide ([NO]) + nitrogen dioxide ([NO2])) throughout the continental United States (U.S.) have important implications for tropospheric ozone (O3) and reactive oxidized nitrogen chemistry (NOy ≈ NOx + nitric acid (HNO3) + particle nitrate (pNO3) + peroxy nitrates (PNs) + alkyl nitrates (ANs)). Specifically, decreasing [NOx] concentrations have likely (1) increased the sensitivity of O3 to the [NOx] level, and (2) affected NOy speciation and partitioning. An understanding of the impacts of continued [NOx] reductions is needed to inform current and future air pollution control strategies, especially since the National …

Novel Bioreactor Technology For Real Time In-Cell Nmr, Leonard Breindel

Legacy Theses & Dissertations (2009 - 2024)

Long has it been the goal of biochemists to observe a protein within the cellular environment allowing the true nature of a protein function to be determined within a cell. To understand the nature of a protein within a cell, the role of the cellular environment must be considered when determining the function as a protein. The cellular environment is a crowded place filled with macromolecules such as DNA, RNA and proteins that all interact with one another affecting the function of a protein. Intracellular macromolecules can reach concentrations of 300 g/L and occupy 30% of the available space in …

Towards Machine Learning In Chemical Sensing : Milk Differentiation And Quality Control Through Two-Dimensional Nano-Sensor Array, Yu Sheng Chen

Legacy Theses & Dissertations (2009 - 2024)

Herein, we developed a novel artificial tongue using machine learning and 12 nanoassemblies (2D-NAs) to identify and analyzed different kinds of milk beverages for quality control. This biomimetic sensor array was trained to “taste” different milk types as an “artificial tongue” which is the first time we demonstrated that this sensor array can be implemented to complex systems. Two-dimensional nanoparticles (2D-nps) and nine fluorescently labeled single stranded oligonucleotides (ssDNA) with different length and nucleobases were assembled to create 12 2D-NAs. The artificial tongue was deployed to identify and analyze five milk types. All five milk types were discriminated with 95% …

Elemental Composition And Arsenic Speciation Analysis Of Processed Seafood Products Using Atomic Spectrometric Techniques, Austin A. Roberts

Legacy Theses & Dissertations (2009 - 2024)

Arsenic (As) is a widely known toxic element that is highly ubiquitous and has been detected in soil, sediment, naturals waters, the atmosphere, and in organisms of the 5 kingdoms. The toxicity of As however, is dependent on the molecular form in which it takes as well as the route of exposure. For the general population, exposure to As mainly takes place via ingestion of food and water, which have led to numerous studies investigating As and it’s various species in these matrices. Seafood is one of the major sources of dietary exposure to As and has thus led to …