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Optimized Peptide Nanomaterials As Delivery Vehicles For Hydrophobic Metal-Based Anticancer Agents, Yaron Marciano 2023 The Graduate Center, City University of New York

Optimized Peptide Nanomaterials As Delivery Vehicles For Hydrophobic Metal-Based Anticancer Agents, Yaron Marciano

Dissertations, Theses, and Capstone Projects

Enzyme-responsive materials have been well explored, particularly as therapeutic and diagnostic agents. In this thesis we demonstrate that anionic self-assembling peptides can be utilized as delivery vehicles for metal-based hydrophobic payloads. The tunability of the system is highlighted as well as the increase in cytotoxicity and selectivity in vitro. The rapid degradation of peptides in cell media may lead to the formation of new peptide-drug bioconjugates with increased activity and selectivity. The physiological stability of these peptide delivery vehicles has been optimized by capping the N-terminus with an acetyl group. This simple backbone modification was shown to not prevent self-assembly, …


The Boozi Device’S Effect On Aroma Compounds In Distilled Spirits, Drew Budner, Lindsey Bell, Katherine Thompson-Witrick 2023 Coastal Carolina University

The Boozi Device’S Effect On Aroma Compounds In Distilled Spirits, Drew Budner, Lindsey Bell, Katherine Thompson-Witrick

Journal of the South Carolina Academy of Science

The BooZi is a commercially available flavor-modifying device that claims to remove the negative flavor agents (congeners) from a number of different types of distilled spirits and wines. SPME was utilized for the extraction of the volatile and semi-volatile compounds within each sample. The analysis of the compounds found in the samples following exposure to the BooZi device were analyzed using a GC-MS. The most significant changes regarding the aroma profile of the distilled spirits were noticeable following 96 hours of exposure. The BooZi device was shown to be effective in reducing the concentration of a number of compounds, including …


Determination Of Total Ammonia Nitrogen By Gas-Diffusion Flow Injection Analysis (Gd-Fia)-Spectrophotometry Using Minnieroot Flower (Ruellia Tuberosa) As Natural Reagent, Lani Artana Putri, Puspita Mufidah Sari, Hermin Sulistyarti, Akhmad Sabarudin, Erwin Sulistyo 2022 Department of Chemistry, Faculty of Sciences, Universitas Brawijaya, Malang 65145, Indonesia

Determination Of Total Ammonia Nitrogen By Gas-Diffusion Flow Injection Analysis (Gd-Fia)-Spectrophotometry Using Minnieroot Flower (Ruellia Tuberosa) As Natural Reagent, Lani Artana Putri, Puspita Mufidah Sari, Hermin Sulistyarti, Akhmad Sabarudin, Erwin Sulistyo

Makara Journal of Science

Total ammonia nitrogen (TAN) is a pollutant agent found in water and generated from the metabolisms of living organisms and the decomposition of organic matter. This research aims to develop an efficient, low-cost, and environmentally friendly TAN analysis method. The principle of this method is based on the reaction of TAN injected in the donor stream with NaOH to form alkaline gaseous ammonia. The gaseous ammonia diffuses through a hydrophobic membrane into an acceptor stream containing Ruellia tuberosa extract. The presence of NH3 gas in the acceptor stream changes the extract color from pinkish to green, which is monitored …


An Imaging Mass Spectrometry Investigation Into The N-Linked Glycosylation Landscape Of Pancreatic Ductal Adenocarcinoma And The Development Of Associated Tools For Enhanced Glycan Separation And Characterization, Colin McDowell 2022 Medical University of South Carolina

An Imaging Mass Spectrometry Investigation Into The N-Linked Glycosylation Landscape Of Pancreatic Ductal Adenocarcinoma And The Development Of Associated Tools For Enhanced Glycan Separation And Characterization, Colin Mcdowell

MUSC Theses and Dissertations

The severity of pancreatic ductal adenocarcinoma (PDAC) is largely attributed to a failure to detect the disease before metastatic spread has occurred. CA19-9, a carbohydrate biomarker, is used clinically to surveille disease progression, but due to specificity challenges is not suitable for early discovery. As CA19-9 and other prospective markers are glycan epitopes, there is great clinical interest in understanding the glycobiology of pancreatic cancer. Unfortunately, few studies have been able to link glycosylation changes directly to pancreatic tumors and instead have focused on peripheral glycan alterations in the serum of PDAC patients. To address this gap in our understanding, …


Intra-Skeletal Variation In Stable Isotopes Through Non-Destructive Approaches: Applications Of The Patterns Of Skeletal Remodeling To Biological Anthropology, Armando Anzellini 2022 University of Tennessee, Knoxville

Intra-Skeletal Variation In Stable Isotopes Through Non-Destructive Approaches: Applications Of The Patterns Of Skeletal Remodeling To Biological Anthropology, Armando Anzellini

Doctoral Dissertations

Stable isotope analysis is a well-established method in biological anthropology used to deliver data on residence, diet, and life history. Samples for these analyses are often collected from the diaphyses of long bones with an assumption of an expected rate of turnover between five and ten years, depending on the skeletal element. However, the biological foundations of this assumption are still uncertain, especially concerning the intra-skeletal and intra-element variation of isotopic signatures that may relate to patterns of remodeling. Exploring these gaps in intra-element isotopic variation requires fine-grained work using multiple bones from multiple individuals, but such work is limited …


Analytical Techniques For The Analysis Of Uranium Bearing Materials, Nathaniel D. Fletcher 2022 University of Tennessee, Knoxville

Analytical Techniques For The Analysis Of Uranium Bearing Materials, Nathaniel D. Fletcher

Doctoral Dissertations

The interest in the use of nuclear power has increased drastically in recent years. This is due to significantly increased efficiency at producing energy when compared to fossil fuels. With the increased use of nuclear power comes an increased need to for monitor for uranium bearing materials outside of regulatory control. This dissertation covers four projects aimed at improving the analysis of these materials. The first projects aims to develop a method that allows for the analysis of elements that exist in nature as anions by triple quadrupole ICP – MS. This would allow for the ability to measure more …


Light Matter Interactions: A Study Of Soft Materials Using Linear And Nonlinear Spectroscopy, Muhammad Redwan Hassan 2022 University of Tennessee, Knoxville

Light Matter Interactions: A Study Of Soft Materials Using Linear And Nonlinear Spectroscopy, Muhammad Redwan Hassan

Doctoral Dissertations

The adoption of complex fluids for various industrial applications is becoming normal. Complex fluids offer tunability, wide range solubility, and chemical and thermal stability which are the factors that conventional polar and non-polar solvents often lack. However, fundamental studies of these fluid systems are still lacking which is limiting the appropriate use of these complex fluids in many applications. The goal of this dissertation was to study and characterize complex fluids for application in electrolytes for redox flow batteries. Chapter 3 and chapter 4 feature the study of microemulsions and deep eutectic solvents (DES) by fluorescence techniques. Fluorescence studies of …


Achieving Safe Use Of Advanced Materials In Drinking Water Through Novel Nano Analytics And Enabling Electrification Using Green Catalyst, Kenneth Ray Flores 2022 University of Texas at El Paso

Achieving Safe Use Of Advanced Materials In Drinking Water Through Novel Nano Analytics And Enabling Electrification Using Green Catalyst, Kenneth Ray Flores

Open Access Theses & Dissertations

The accumulation of engineered nanomaterials (ENMs) in environmental sectors will continue to increase as more applications are discovered for their unique properties and characteristics. Additionally, the presence of nanomaterials in the environment becomes exacerbated as more consumer products containing nanoparticles are approved for use. It is debated whether the toxic effects of nanoparticles stem from the particles themselves, ionic species, or formation of secondary particles. Therefore, understanding the behavior of nanoparticles in the environment becomes key to discerning the toxicological effects of nanoparticles. Many advancements have been made with ICP-MS to understand the behavior of nanoparticles in the environmental systems, …


Computational And Experimental Investigations Of Alkali Cation Interactions At The Rutile – Water Interface, Isaac Johnston 2022 Clemson University

Computational And Experimental Investigations Of Alkali Cation Interactions At The Rutile – Water Interface, Isaac Johnston

All Dissertations

Overall, the objective of this dissertation was to investigate the degree of sorption for the alkali cations on rutile to ascertain the impact of different cation properties, such as ion size and charge density, on sorption mechanics as well as probe how the ion may alter the surface – aqueous interface. Initial molecular dynamic simulations and batch experiments showed minimal surface sorption for any alkali cation at relatively low concentrations while simultaneously suggesting the enthalpy of deprotonation shifts slightly in the presence of the alkali cations at different ionic strengths. The cations are likely causing small reorientations of the near-surface …


Near-Ir Laser Ablation Of Simulated Radiologically Contaminated Oxides On Carbon Steel Feeder Pipes, Thao Viet Do 2022 The University of Western Ontario

Near-Ir Laser Ablation Of Simulated Radiologically Contaminated Oxides On Carbon Steel Feeder Pipes, Thao Viet Do

Electronic Thesis and Dissertation Repository

As nuclear power plants age and retire from service, many countries face significant challenges concerning the safe long-term storage and disposal of large volumes of low and intermediate level radioactive wastes (L&ILW). The volumes of metallic waste are of particular concern, as when metal corrodes it produces hydrogen that could lead to pressure build-up in interim storage and disposal. In Canada, a significant fraction of the metallic wastes for Canada Deuterium Uranium (CANDU) nuclear reactors are out-of-core reactor components, such as carbon steel (CS) feeder pipes. The radioactive contamination is expected to be largely confined to the surface oxide layers …


Developing Carbon Quantum Dots As A Luminescent Material And Revisiting Ecl And Led Absolute Measurement Methods, Jonathan Ralph Adsetts 2022 The University of Western Ontario

Developing Carbon Quantum Dots As A Luminescent Material And Revisiting Ecl And Led Absolute Measurement Methods, Jonathan Ralph Adsetts

Electronic Thesis and Dissertation Repository

Luminescent materials play increasingly important roles in our lives. Improvements in these materials’ quantum efficiencies (QEs), costs and toxicity can greatly reduce the power consumption, price and environmental damage to the planet, respectively. Carbon quantum dots (CQDs) and luminescent materials exhibiting thermally activated delayed fluorescence (TADF) are two interesting materials in these aspects. Furthermore, measurements on electrochemiluminescence (ECL) and electroluminescence of these luminescent materials can quickly evaluate their performance for many applications. In this thesis, controlled CQD syntheses are revealed beneficial to luminescent materials applications. Their film ECL demonstrated relatively stable anionic and cationic radicals leading to high emission at …


Validation Of A Method For Pantoprazole And Its Sulfone Metabolite In Goat Plasma Using High Performance Liquid Chromatography, Sherry Cox, Lainey Harvill, Sarah Bullock, Joseph Smith, Joan Bergman 2022 UTK

Validation Of A Method For Pantoprazole And Its Sulfone Metabolite In Goat Plasma Using High Performance Liquid Chromatography, Sherry Cox, Lainey Harvill, Sarah Bullock, Joseph Smith, Joan Bergman

Faculty Publications and Other Works -- Large Animal Clinical Sciences

No abstract provided.


Concentration Of Heavy Metals In Three Distinct Algae Families From Humboldt County, California, Kodiak E. Miller, Caleb J. Strait, Jacob I. Begorre, Brittney L. Mitchell, Claire P. Till 2022 Cal Poly Humboldt

Concentration Of Heavy Metals In Three Distinct Algae Families From Humboldt County, California, Kodiak E. Miller, Caleb J. Strait, Jacob I. Begorre, Brittney L. Mitchell, Claire P. Till

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

Anthropogenic impacts on marine environments can impact metal fluxes and concentrations available to marine species. Monitoring these impacts is necessary to better understand the interactions between the biotic and abiotic components of these ecosystems and mitigate the risk posed by harmful toxins introduced by human activities. Biomoniters, like macroscopic algae, are useful indicators that illuminate the bioaccumulation of toxins commonly introduced from anthropogenic activity. With this in mind, the concentrations of heavy metals zinc (Zn), nickel (Ni), and copper (Cu) were analyzed via the assessment of algae (Representatives from Ulva, Mastocarpus, Fucus) in two sites in Humboldt County: …


Conformational Dynamics And Aggregation Of Thermally Stressed Proteins Studied By Hydrogen/Deuterium Exchange Mass Spectrometry, Nastaran Nosrat Tajoddin 2022 The University of Western Ontario

Conformational Dynamics And Aggregation Of Thermally Stressed Proteins Studied By Hydrogen/Deuterium Exchange Mass Spectrometry, Nastaran Nosrat Tajoddin

Electronic Thesis and Dissertation Repository

Proteins perform various biological functions, e.g., as enzymes or transporters. In addition to naturally occurring proteins, the use of protein therapeutic drugs for treating cancer and other diseases is a rapidly growing area. A thorough biophysical characterization of proteins and protein therapeutics opens the door to a more comprehensive understanding of their role in health and disease. This dissertation aims to expand the capabilities of an existing technique (Hydrogen Deuterium Exchange Mass Spectrometry, HDX-MS), which is widely used for probing protein structure and dynamics. Conventionally, HDX-MS experiments are performed as a function of labelling time. Here we aim to establish …


Intracellular Delivery Of Therapeutic Biomolecules Through Versatile Polymer Nanotechnology, David C. Luther 2022 University of Massachusetts Amherst

Intracellular Delivery Of Therapeutic Biomolecules Through Versatile Polymer Nanotechnology, David C. Luther

Doctoral Dissertations

Advancing pharmaceutical technology has made it possible to treat diseases once considered ‘undruggable.’ Access to these new pharmaceutical targets is possible thanks to the advent of protein and nucleic acid therapeutics. Responses to the COVID-19 pandemic, as well as cutting-edge treatments for cancer and multiple sclerosis have centered on these biologic therapies, promising even greater value in the future. However, their utility is limited at a cellular level by inability to cross the plasma membrane. Nanocarrier technologies encapsulate therapeutics and facilitate uptake into the cell but are often trapped and degraded in endosomes. Arginine-functionalized gold nanoparticles (Arg-NPs) provide efficient, direct …


Investigating The Mechanism Of Protein And Peptide Electrospray Ionization, Elnaz Aliyari 2022 The University of Western Ontario

Investigating The Mechanism Of Protein And Peptide Electrospray Ionization, Elnaz Aliyari

Electronic Thesis and Dissertation Repository

Electrospray ionization (ESI) mass spectrometry (MS) is widely used for the detection and characterization of various analytes. However, many fundamental aspects of the ESI process remain poorly understood. Using molecular dynamics (MD) simulations, MS, and ion mobility spectrometry (IMS), this thesis sheds light on the mechanisms whereby gaseous analyte ions are formed from highly charged ESI nanodroplets. After a general introduction (Chapter 1), Chapter 2 focuses on the ion evaporation mechanism (IEM), i.e., the ejection of analyte ions from the droplet surface. The IEM is well established for low MW compounds, but it has remained contentious whether this pathway is …


Using Ftir-Atr And Chemometric Methods To Detect Sucrose Adulteration In Commercial Honey Samples, Dylan T. Roberts, Kevin Kittredge 2022 Virginia Wesleyan University

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

Virginia Journal of Science

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


Natural Product Discovery And Mycotoxin Analysis Of Agricultural Endophytes And Pathogens, Jacob P. Walsh 2022 The University of Western Ontario

Natural Product Discovery And Mycotoxin Analysis Of Agricultural Endophytes And Pathogens, Jacob P. Walsh

Electronic Thesis and Dissertation Repository

This thesis focuses on the application of fungal natural product chemistry for the use of agriculture fungal pathogenesis research. The research in this work uses many analytical chemistry techniques and instruments such as HPLC, LC-MS/MS and NMR. In Chapter 2, a diagnostic fragmentation module was developed for the identification of compound classes in crude fungal extracts. This module identified the classes cytochalasins and chaetoglobosins from extracts of Penicillium, Chaetomium, and Xylaria. From these extracts a new chaetoglobosin was discovered and the module was implemented into the open-source software package MZmine 2.0. Chapter 3 discusses analytical chemistry techniques with the …


Sensitized Photooxidation Of Prenylated Compounds: Mechanisms Of Downstream Dark Effects And Phototoxicity Priming, Shakeela Jabeen 2022 The Graduate Center, City University of New York

Sensitized Photooxidation Of Prenylated Compounds: Mechanisms Of Downstream Dark Effects And Phototoxicity Priming, Shakeela Jabeen

Dissertations, Theses, and Capstone Projects

This thesis consists of four chapters as detailed below.

Chapter 1 discusses a singlet oxygen priming mechanism. Airborne singlet oxygen derived from photosensitization of triplet dioxygen is shown to react with an alkene surfactant (8-methylnon-7-ene-1 sulfonate) leading to ‘ene’ hydroperoxides that in the dark inactivate planktonic E. coli. The ‘ene’ hydroperoxide photoproducts are not toxic on their own, but they become toxic after the bacteria are pretreated with singlet oxygen. The total quenching rate constant (kT) of singlet oxygen of the alkene surfactant was measured to be 1.1 × 106 M1 s− …


Analyzing Enhanced Electrochemiluminescence Of Novel Materials, Liuqing Yang 2022 The University of Western Ontario

Analyzing Enhanced Electrochemiluminescence Of Novel Materials, Liuqing Yang

Electronic Thesis and Dissertation Repository

As a powerful analytical technique, electrochemiluminescence (ECL) has found wide applications in the fields of bioanalysis and light-emitting devices. However, many ECL materials sustain the shortcomings of low ECL efficiencies. To better design novel materials with ECL enhancement, it is essential to investigate and the enhanced ECL mechanisms. In this thesis, ECL enhancements of various novel materials were analyzed utilizing ECL-voltage curves, potential pulsing experiments, ECL and photoluminescence spectroscopies, and other characterization methods. Specifically, two graphene quantum dots (GQDs) with different heteroatom doping were designed and synthesized. Structural characterizations and spectroscopies demonstrated that the heteroatom doping could change the surface …


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