Chemistry Commons^™

Gold Nanoparticles/Over-Oxidized Poly-Eriochrome Black T Film Modified Electrode For Determination Of Arsenic, Mürşi̇de Ceren Afşar, Aydan Elçi̇, Zekerya Dursun

Turkish Journal of Chemistry

A glassy carbon electrode, modified with gold nanoparticles/over-oxidized poly-eriochrome black T film, was fabricated for sensitive determination of As(III) by stripping voltammetry in an acidic medium. The electrode surface properties were characterized by cyclic voltammetry, electrochemical impedance spectroscopy, scanning electron microscope (SEM), and X-ray photoelectron spectroscopy (XPS). The electrode demonstrated a good response towards As(III), with a detection of 0.077 μM and good linearity in the range of 0.1 to 10 μM (R² = 0.9977). For the determination of As(III), the fabricated electrode was placed in different mineral water samples, acidified with 0.75 M HCl solution, spiked with various …

Electroanalytical Investigation And Voltammetric Quantification Of Antiviral Drug Favipiravir In The Pharmaceutical Formulation And Urine Sample Using A Glassy Carbon Electrode In Anionic Surfactant Media, Zeynep Akca, Hande İzem Özok, Yavuz Yardim, Zühre Şentürk

Turkish Journal of Chemistry

This work describes the electrochemical investigation of a promising antiviral agent, favipiravir (FAV) utilizing a nonmodified glassy carbon (GC) electrode, along with a unique voltammetric approach that can determine FAV with a good degree of accuracy, speed, and cost-effectiveness. Using cyclic voltammetry, the compound demonstrated a single well-defined and an irreversible oxidation peak at approximately +1.12 V (vs. Ag/AgCl) in Britton-Robinson (BR) buffer at pH 10.0. The synergistic effect of anionic surfactant, sodium dodecyl sulfate (SDS) on the adsorption ability of GC electrode remarkably increased the sensitivity of the stripping voltammetric measurements of FAV. Employing square-wave adsorptive stripping voltammetry at …

Impacts Of Some Metal Ions On Glutathione S-Transferase In The Liver Of Chalcalburnus Tarichi: An Endemic Species Of Lake Van, Muhammet Serhat Özaslan, Mehmet Çi̇ftci̇

Turkish Journal of Chemistry

Glutathione-S-transferase (GSTs) is a multifunctional enzyme that provides homeostasis by catalyzing the first step of the formation of mercapturic acid, the end product in detoxification metabolism. They can prevent reactive electrophilic compounds from harming the body by covalently binding the same type of compounds to each other. In this study, we determined the in vitro inhibitory effects of metal ions such as Cu2+, Cd2+, Ag+, and Co2+ on GST enzyme activity. For this aim, GST was purified from C. tarichi Pallas liver with 37.36% yield and 29.304 EU/mg specific activity using the chromatographic method. The Vmax values of liver GST …

Preparation And Characterisation Of Ethambutol With Β-Cyclodextrin: A Comprehensive Molecular Insight Into Host-Guest Interaction, Soen Qeng Goh, Qiao Hui Chan, Rohana Adnan, Nurul Yani Rahim

Turkish Journal of Chemistry

The increase in new cases of drug resistance to first-line drugs such as ethambutol (ETB) makes it necessary to develop improvements for antituberculosis drugs. A new method for improving the bioavailability of active pharmaceutical ingredient (API) was investigated for preventing drug resistance and side-effects of antituberculosis drugs. In this study, an antituberculosis drug delivery system using β-cyclodextrin (β-CD) as the supramolecular carrier of ETB was prepared using the kneading method. The inclusion behaviour of β-CD/ETB inclusion complex in solid and liquid state was investigated. The inclusion complex was characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, nuclear magnetic resonance (NMR) …

The Significance Of A New 11,000-Year Volcanic Record From The South Pole And Inferences From Comparisons With Other Volcanic Records, Derek Lee Brandis

Electronic Theses and Dissertations

Snow accumulation at the polar regions of the planet preserves chemical substances from the atmosphere creating natural archives. Records of the atmospheric environment including atmospheric chemical composition and the climate can be reconstructed from ice cores from the polar ice sheets. Sulfur emitted by explosive volcanic eruptions is preserved as sulfate in polar snow and can be used to reconstruct the record of volcanic eruptions. Since large volcanic eruptions impact the environment and climate, records of volcanic eruptions from ice cores can help us to study and understand climate change and model the future climate environment. A 1750-m ice core …

Students’ Perceptions Of Specific Laboratory Curricula On The Learning Experience In Chemistry Courses, Arwa Ali Alshehri

Electronic Theses and Dissertations

Laboratory courses play a key role in developing critical thinking and problem-solving skills and providing experience in certain aspects of a laboratory setting including reactions, materials, and equipment. Prior studies suggest that a laboratory course assists students toward cognitive gain on lecture content. In contrast, other studies conclude that laboratory is uncorrelated with cognitive gain on lecture content. Thus, a discord exists between researchers regarding the role that laboratory experiences play in furthering the understanding of chemistry concepts taught in lectures. The purpose of this research is to examine the impact of two different laboratory curricula on students’ performance in …

Development Of Terpyridine-Based Metallosurfactants For Directional Electron Tunneling, Samudra Subashini Amunugama

Wayne State University Dissertations

The molecular electronics field is a multidisciplinary area that addresses the utilization of molecules as the basic unit of electronic components. Depending on the characteristics of the molecules, they can function as transistors, wires, switches, and memory cells. This field has attracted significant interest from the scientific community due to the increasing number of issues associated with the miniaturization process of microelectronic devices and the desirability of using molecules in electronic circuits. The research work discussed in this dissertation thesis is focused on the design and development of terpyridine-based metallosurfactant as prospective candidates for molecular electronics. Since rectifiers are pivotal …

Synthesis Of Highly Reactive Sulfone Iminium Fluorides And Their Use In Deoxyfluorination And Sulfur Fluoride Exchange Chemistry, James A. Vogel, Rania Hammami, Ara Ko, Hiya Datta, Yael N. Eiben, Karley J. Labenne, Ellis C. Mccarver, Ebrar Z. Yilmaz, Patrick R. Melvin

Chemistry Faculty Research and Scholarship

We report the synthesis of sulfone iminium fluorides (SIFs), a reactive class of sulfur(VI) molecules. The synthesis is tolerant of a variety of substituents on the sulfur and nitrogen components. The SIF reagents were applied to the deoxyfluorination of alcohols and carboxylic acids, providing high yields of fluorinated products in 60 s at room temperature. The SIF reagents were then utilized in sulfur fluoride exchange (SuFEx), creating the first ionic SuFEx products to date.

Electron Deficient Fluoroarenes: Bridging Deoxyfluorination And Anion-Π Interactions To Produce New Fluorination Reagents, Jordan Houston Kramer

Dissertations and Theses

Fluorination is a ubiquitous in modern materials and pharmaceuticals due to organofluorine compounds possessing unique physicochemical properties. However, this process is a demanding task due to difficulty in handling key reagents for selective fluorination. One strategy is the usage of deoxyfluorination reagents due to the wide availability of oxygen in many functional moieties. These reagents have allowed to production of new fluorinated materials and pharmaceuticals, yet the costs of several reagents and instabilities for others lead to restricted conditions, functional group tolerance, and safety risks for both users and the environment. Reported here is the culmination of a new hypothesis …

Mapping The Dna Damaging Effects Of Polypyridyl Copper Complexes With Dna Electrochemical Biosensors, Anna Banasiak, Nicolò Zuin Fantoni, Andrew Kellett, John Colleran

Articles

Several classes of copper complexes are known to induce oxidative DNA damage that mediates cell death. These compounds are potentially useful anticancer agents and detailed investigation can reveal the mode of DNA interaction, binding strength, and type of oxidative lesion formed. We recently reported the development of a DNA electrochemical biosensor employed to quantify the DNA cleavage activity of the well-studied [Cu(phen)₂]²⁺ chemical nuclease. However, to validate the broader compatibility of this sensor for use with more diverse—and biologically compatible—copper complexes, and to probe its use from a drug discovery perspective, analysis involving new compound libraries is …

Partially Oxidised Boron Nitride As A 2d Nanomaterial For Nanofiltration Applications, Natalia Garcıa Domenech, Aine Coogan, Finn Purcell Milton, María Luisa Casasín Garcia, Adrián Sanz Arjona, Marc Brunet Cabré, Aran Rafferty, Kim Mckelvey, Peter Dunne, Yurii K. Gun'ko

Articles

Access to clean water has become increasingly scarce in recent years due to various factors, such as increasing population density, urbanisation, and inequality, among others.1 The development of new, inexpensive, and reliable methods for the removal of various impurities and toxins from water is therefore vital. In recent years, the emergence of nanofiltration (NF) membranes has become an exciting prospect for water purification. NF can be described as a type of filtration which exhibits separation characteristics in between reverse osmosis and ultrafiltration, and typically has molecular weight cut-offs in the region of 200–1000 Daltons.2,3 Various nanomaterials have been implemented in …

Expression And Purification Of A Cleavable Recombinant Fortilin From Escherichia Coli For Structure Activity Studies, Maranda S. Cantrell, Jackson D. Wall, Xinzhu Pu, Matthew Turner, Luke Woodbury, Owen M. Mcdougal, Lisa R. Warner

Chemistry and Biochemistry Faculty Publications and Presentations

Complications related to atherosclerosis account for approximately 1 in 4 deaths in the United States and treatment has focused on lowering serum LDL-cholesterol levels with statins. However, approximately 50% of those diagnosed with atherosclerosis have blood cholesterol levels within normal parameters. Human fortilin is an anti-apoptotic protein and a factor in macrophage-mediated atherosclerosis and is hypothesized to protect inflammatory macrophages from apoptosis, leading to subsequent cardiac pathogenesis. Fortilin is unique because it provides a novel drug target for atherosclerosis that goes beyond lowering cholesterol and utilization of a solution nuclear magnetic resonance (NMR) spectroscopy, structure-based drug discovery approach requires milligram …

Synthesis Of Molybdenum Containing Thin Films Using Organic Reducing Agents And Synthesis Of Magnesium Silyl Intermediate Complexes For Use In Atomic Layer Deposition, Michael David Overbeek

Wayne State University Dissertations

Thin films of a variety of materials have shown great potential in the fields of microelectronics, catalysis, and energy applications. Vapor deposition methods, including PVD and CVD, have been traditionally used as the primary method to deposit these thin films. However, these methods do not provide the necessary thickness uniformity and conformality needed for future uses of these thin films as they shrink to smaller dimensions. ALD provides a high degree of uniformity and conformality due to the intrinsic nature of the self-limited reaction mechanism of an ALD process.

The research herein focuses on two metals that have untapped potential …

Stoichiometry Question Sets, Myungshim Kang

Open Educational Resources

This is a question pool for general chemistry. This consists of question sets, each of which contains variations of questions for topics, including the mole, molar mass, balancing chemical equations, and quantitative relationships in chemical reactions.

Investigation Of Biological Activities Of Plant Extract And Green Synthesis Silvernanoparticles Obtained From Gilaburu (Viburnum Opulus L.) Fruits, Bi̇rgütay Şahi̇n, Ali̇ Savaş Bülbül, İbrahi̇m Seyfetti̇n Çeli̇k, Nesri̇n Korkmaz, Ahmet Karadağ

Turkish Journal of Chemistry

In this study, biological activities of silver nanoparticles (AgNP) synthesized by green synthesis method using the fruit extract of Gilaburu (Viburnum opulus L.) plant were investigated. The characterization of the synthesized AgNPs was performed by ultraviolet visible region spectroscopy (UV-Vis), Fourier transform - infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD) techniques. The crystal size was found to be 52.32 nm when the XRD data were calculated with the Debye- Scherrer's equation. The antimicrobial activities of extract and AgNPs were investigated by microdilution and disk diffusion methods. Antibiofilm activities were examined by the crystal violet technique. The …

Microstructure And Ionic Conductivity Investigation Of Samarium Doped Ceria(Sm0.2ce0.8o1.9) Electrolytes Prepared By The Templating Methods, Di̇lara Güçtaş, Vedat Sariboğa, Mehmet Ali̇ Faruk Öksüzömer

Turkish Journal of Chemistry

Sm0.2Ce0.8O1.9 (SDC20) electrolytes were synthesized with cellulose templating (CT) and PVA templating (PVAT) methods. Powder characteristics were examined using TG/DTA, XRD, and SEM. Pellets are sintered at various temperatures for different durations. Mean grain sizes were calculated from SEM micrographs using the linear intercept method. Grain growth behavior of the electrolytes was investigated and the dominant diffusion mechanism was examined. The grain growth activation energies were obtained for the first time for the mentioned electrolytes prepared by the mentioned methods. The ionic conductivities were calculated by electrochemical impedance spectroscopy. The highest ionic conductivity value was found to be 0.050 S …

Fluorescent Labelling Of Ribosomal Rna In Live Mammalian Cells, Amir Agharezaee

Legacy Theses & Dissertations (2009 - 2024)

This thesis describes a bio-orthogonal chemistry-based approach for new methods of fluorescence labelling of RNA in live HeLa cells via an IEDDA reaction of TCO with tetrazine. The key step of the approach is synthesis of two nucleobase analogues which were modified with TCO and a masked 5′-phosphate group using aryl phosphonamidite chemistry. Synthesis of tubercidin and uridine analogues were considered in this investigation for incorporation into RNA in live HeLa cells. Synthetic approach was successful at installing the handle containing TCO to tubercidin and uridine to make compounds 12 and 21 respectively (the synthesis of both of which are …

Photopolymers : Environmentally Benign Technology For A Variety Of Industries, Tatyana Tarasevich

Legacy Theses & Dissertations (2009 - 2024)

Photopolymerization is a well-known process with applications in a variety of industries. Photopolymers are formed by a reaction of monomers or oligomers, photoinitiators and in some cases crosslinkers. Upon irradiation with UV or visible light, monomers undergo conformational change to form polymers via a photochemical process. Several photopolymerization types will be discussed in this thesis. End products of photopolymerizations included epoxies, inks, coatings, photoresists, etc.

Synthesis Of Oligonucleotides Containing Unnatural Backbone And Regulation Of Crispr Activity Using Inverse Electron Demand Diels-Alder Chemistry, Alyssa Hoy

Legacy Theses & Dissertations (2009 - 2024)

This thesis describes the synthesis of an oligonucleotide containing an unnatural neutralbackbone. The backbone was constructed using bio-orthogonal inverse electron demand Diels- Alder chemistry between trans-cyclooctene (TCO) and tetrazine (Tz). A TCO phosphoramidite was synthesized and attached to solid support for strand propagation. Uridine monomers containing either bis-TCO or bis-Tz were also synthesized. The oligonucleotide strand was formed by sequential ligation of the bis-Tz and bis-TCO monomers. The oligonucleotide was analyzed using mass spectrometry. This thesis also describes the synthesis of sgRNAs containing non-canonical nucleobases, m1A, m6A, s2U and s4U using the ‘split-and-click’ methodology. The synthetic sgRNAs were assembled using …

First Homoleptic Rare Rarth Metal Complexes With Doubly-Reduced Dibenzocyclooctatetraene, James C. Mahoney

Legacy Theses & Dissertations (2009 - 2024)

A set of novel complexes of rare earth elements, M(III) = Y, La, Gd, Tb, and Dy, with the doubly-reduced dibenzo[a,e]cyclooctatetraene (DBCOT) anion has been synthesized and crystallographically characterized for the first time. Preparation of new complexes has been accomplished through the ligand-metathesis reaction of M(III) triiodides with K2(DBCOT) in THF at ambient conditions. Subsequent crystallization via slow solvent evaporation afforded single crystals of good quality. X-ray diffraction technique confirmed that all complexes are isomorphous and conform to the [M(DBCOT)(THF)4][M(DBCOT)2] composition. In their crystal structures, the monoanionic double-decker sandwiches, [M(DBCOT)2], weakly interact with the cationic counterparts, [M(DBCOT)(THF)4]+. In both parts, …

Uio-Type Metal-Organic Framework Derivatives As Sorbents For The Detection Of Gas-Phase Explosives, Matthew Ryan Sherrill

Legacy Theses & Dissertations (2009 - 2024)

The detection of energetic compounds – better known to the public as explosives – has is an important cornerstone of counterterrorism and homeland security . While significant advances have been achieved for the detection of trace explosives in various matrices such as soil, wastewater, and clothing, the detection of explosives in the gas phase remains challenging due to their infamously low vapor pressures. In this thesis, we leverage the high sensitivity of direct analysis in real-time mass spectrometry (DART-MS) and the microporosity of metal-organic frameworks (MOFs) to adsorb and therefore concentrate explosives from the vapor phase and subsequently detect them …

Development And Applications Of Touch Chemistry Biometrics Analysis Of Latent Fingermarks By Maldi-Ms, Cameron M. Longo

Legacy Theses & Dissertations (2009 - 2024)

Fingerprint evidence has long been a pillar of forensic science and has been used for over a century as a means of identifying an individual. This is accomplished through the comparison of friction ridge patterns, which are inherently unique to each individual, and the practice of visualizing fingerprints and comparing them has become a well-studied field. While these techniques have been optimized and improved over time, they generally rely only on the physical pattern to provide information about the donor, and not the content of the fingerprint material itself. In the modern era, steps have been made to extract from …

Discrimination Between Human And Non-Human Blood Using Raman Spectroscopy And A Self-Reference Algorithm For Forensic Purposes : Method Expansion And Validation, Harrison Dickler

Legacy Theses & Dissertations (2009 - 2024)

Determining whether the origin of a bloodstain is human or non-human is an important capability of a forensic investigation. In their pioneering work, Bian et al. (Journal of biomedical optics, 2017) introduced a self-reference peak algorithm for the analysis of bloodstain Raman spectra and demonstrated a great potential of this approach for differentiating human and nonhuman blood. However, this work only used three non-human species in the creation of their model. This study investigates the capability of a self-referencing peak algorithm to discriminate between human and 18 non-human species based on the Raman spectra of blood samples. The intensity ratios …

Methodology Studies For Dearomatized Dimer And Beta-Lactone-Mediated Native Chemical Ligation In Organic Synthesis, Xinhao Fan

Legacy Theses & Dissertations (2009 - 2024)

Chapter 1: Dimers of naphthalenol derivatives were synthesized by photocatalysis, cobalt(II) acetylacetonate. Several functional groups were tolerant of its skeleton. This novel dimer was connected through a reversible sigma bond. Its reversibility was confirmed by chiral HPLC and 1H-NMR experiments. Through EPR and Stern-Volmer quenching experiments, we proposed the reaction mechanism. The reversibility property can be potentially beneficial in polymers, self-healing, and memory materials.Chapter 2: We report an epimerization-free native chemical ligation reaction by β-lactone-mediated peptides. This approach can achieve Thr-Xaa efficiently and rapidly. Besides, it has a broad side-chain tolerance. Through the competition reaction experiment, it was demonstrated that …

The Photo-Transformation Of Free Methionine In The Presence Of Surrogate And Standard Isolate Dissolved Organic Matter Under Sunlit Irradiation, Benjamin J. Mohrhardt

Dissertations, Master's Theses and Master's Reports

Sulfur (S)-containing amino acids are key sources of carbon, nitrogen, and sulfur involved in protein synthesis, protein function, and providing energy for microbial growth. Dissolved free and combined methionine is one of two S-containing amino acids incorporated into proteins and has been attributed to their stability and function. The oxidation of methionine has received considerable attention given its ubiquitous presence in most biological systems and has been associated with losses in protein function and pathological disorders. In natural waters, methionine is rapidly and selectively taken up by microorganisms to achieve cellular requirements of carbon, nitrogen, and sulfur. The abiotic transformation …

Spatial Geochemical Changes In Central And East Texas Soils Over Time Resulting From Human Decomposition, Isabela Marisol Overturf

CMC Senior Theses

Human decomposition is studied to aid forensic investigations and better understand the impact of cemeteries on urban resources like soil and groundwater. The purpose of this study was to identify changes in soil geochemistry at and around a human grave to search for lateral nutrient movement and possibly identify new patterns in elemental concentrations that could be used in estimating post-mortem intervals (PMIs). At the Forensic Anthropology Research Facility (FARF) at Texas State San Marcos, soil samples were collected from a shallow grave over the course of 54 days to conduct analysis for organic matter content, texture, pH, and bulk …

Soil Literature Research Project, Kathryn Currey

Natural Sciences Student Research Presentations

TOPIC OVERVIEW : TOXINS IN SOILS AND HEALTH OF HUMANS

• Soil contamination happens all the time as a result of various causes, that can be purposeful or accidental (Soil Science Society of America, np). Some common examples of ways that soil is contaminated is through mining, waste disposal and oil drilling, (Misachi, John).

• Soil contamination and a large presence of toxins present in soils from across the world has harmed our planet, the animals and the humans on it (Soil Science Society of America, np).

• For this project I am going to discuss toxins due to soil …

Soil Health, Laini Flessner

Natural Sciences Student Research Presentations

My literature research topic looks at the remediation of soil, specifically through phytoremediation. Phytoremediation is a method of decontaminating soil by using plants that filter out or degrade pollutants (Rahim and Koh 2).

Soils Project, Teagan Wuethrich

Natural Sciences Student Research Presentations

With the mass production of plastic materials throughout the world there is not only significant impacts towards marine life, but also terrestrial environments because of plastic pollution. These plastic products are non-biodegradable and only break down into tiny microscopic pieces of plastic. These microscopic plastics pollute the grounds and soils us humans depend on.

Soils Project, Corinne Wolf

Natural Sciences Student Research Presentations

There are several well known impacts of climate change on our planet, such rising sea levels or warming temperatures. However, I wanted to explore a way in which climate change could potentially impact soils.