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In Vitro Uptake And Biodistribution Of Silver Nanoparticles In Vero 76 Cells, Miriam A. Crane

Browse all Theses and Dissertations

The number of consumer products containing nanomaterials over the last eight years has increased over two-fold. Silver is one of the most commonly used materials in consumer goods nanoparticle fabrication.1 Thus, the uptake and biodistribution of silver nanoparticles (AgNPs) within mammalian cells can provide insight into their possible toxicological effects. In this study, starch-capped AgNPs of an average diameter of 9 ± 5 nm were synthesized via a bottom-up method, and characterized by Raman spectroscopy, transmission electron microscopy (TEM), inductively couple plasma optical emission spectroscopy (ICP-OES), and absorption spectroscopy. Vero 76 cells were incubated with 0.0, 0.1, 1.0, and 3.0 …

Rigorous Computational And Experimental Investigations On Mdm2/Mdmx-Targeted Linear And Macrocyclic Peptides, David J. Diller, Jon Swanson, Alexander S. Bayden, Chris J. Brown, Dawn Thean, David P. Lane, Anthony W. Patridge, Tomi K. Sawyer, Joseph Audie

Chemistry & Physics Faculty Publications

There is interest in peptide drug design, especially for targeting intracellular protein–protein interactions. Therefore, the experimental validation of a computational platform for enabling peptide drug design is of interest. Here, we describe our peptide drug design platform (CMDInventus) and demonstrate its use in modeling and predicting the structural and binding aspects of diverse peptides that interact with oncology targets MDM2/MDMX in comparison to both retrospective (pre-prediction) and prospective (post-prediction) data. In the retrospective study, CMDInventus modules (CMDpeptide, CMDboltzmann, CMDescore and CMDyscore) were used to accurately reproduce structural and binding data across multiple MDM2/MDMX data sets. In the prospective study, CMDescore, …

Coherent Vibrational And Dissociation Dynamics Of Polyatomic Radical Cations, Katharine M. Tibbetts

Chemistry Publications

The ultrafast dynamics of polyatomic radical cat- ions contribute to important processes including energy transfer in photovoltaics, electron transfer in photocataly- sis, radiation-induced DNA damage, and chemical reac- tions in the upper atmosphere and space. Probing these dynamics in the gas phase is challenging due to the rapid dissociation of polyatomic radical cations following elec- tron removal, which arises from excess electronic excita- tion of the molecule during the ionization process. This Concept article introduces the reader to how the pump- probe technique of femtosecond time-resolved mass spectrometry (FTRMS) can overcome this challenge to capture coherent vibrational dynamics on the …

Probing Coherent Vibrations Of Organic Phosphonate Radical Cations With Femtosecond Time-Resolved Mass Spectrometry, Derrick Ampadu Boateng, Mi'kayla D. Word, Katharine M. Tibbetts

Chemistry Publications

Organic phosphates and phosphonates are present in a number of cellular components that can be damaged by exposure to ionizing radiation. This work reports femtosecond time-resolved mass spectrometry (FTRMS) studies of three organic phosphonate radical cations that model the DNA sugar-phosphate backbone: dimethyl methylphosphonate (DMMP), diethyl methylphosphonate (DEMP), and diisopropyl methylphosphonate (DIMP). Upon ionization, each molecular radical cation exhibits unique oscillatory dynamics in its ion yields resulting from coherent vibrational excitation. DMMP has particularly well-resolved 45 fs (732 ± 28 cm−1) oscillations with a weak feature at 610–650 cm−1, while DIMP exhibits bimodal oscillations with a period of ∼55 fs …

Biosensor For The Oxidative Stress Biomarker Glutathione Based On Sam Of Cobalt Phthalocyanine On A Thioctic Acid Modified Gold Electrode, Mohammed Nooredeen Abbas, Ayman Ali Saeed, Mounir Ben Ali, Abdelhamid Errachid, Nadia Zine, Abdullatif Baraket, Baljit Singh

Articles

Self-assembled monolayer (SAM) of cobalt teraaminophthalocyanine (CoTAPc) was developed on thioctic acid (TA) dithiol modified gold electrode and electrochemically evaluated as a glutathione (GSH) selective biosensor. The CoTAPc-TA-Au modified electrode was developed by the covalent immobilization of the CoTAPc as the electrochemical mediator onto previously prepared gold electrode modified with TA (TA-Au) via amid bond formation with the carboxylic group of TA, producing well-organized SAM of the mediator. For comparison, another electrode modified with 3-mercaptopropionic acid (MPA) as a monothiol linker instead of TA was similarly prepared. The electrode surface modification was characterized using SEM, AFM, CV, and EIS. The …

Radium Dial Watches, Zainab Alzoubi

Natural Sciences Student Research Presentations

This slide presentation for the Natural Sciences Poster Session at Parkland College summarizes the history of radium dial watches, including the Radium Girls, and explores whether radium dial watches might still be dangerous.

Organizing 6, 5-Carbon Nanotubes On Dna Origami Arrays, Kathryn A. Pitton

Theses, Dissertations and Capstones

Carbon nanotubes¹ are cylindrical carbon molecules and can be considered to be composed of one atom thick sheets of carbon called graphene. They have been at the forefront of nanochemistry due to their strength and multiple properties such as absorption, fluorescence, semiconduction, and light scattering capability. DNA Origami (DO)² has emerged as a novel domain for molecular design, resulting in the generation of numerous one, two, and three-dimensional structures that have provided platforms for the organization of organic species and inorganic nanoparticles through simple modifications. The use of DNA Origami to control the placement of single walled carbon …

Electrochemical Reduction Of Artemisinin: Chromatographic Identification Of Bulk Electrolysis Products, Faja Ombwayo, Zahilis Mazzochette, Amos Mugweru

College of Science & Mathematics Departmental Research

Artemisinin is a naturally occurring sesquiterpene lactone with an endo-peroxide bond. This drug is used for treatment of many diseases including malaria. The reduction of this molecule on an electrode surface was carried out by cyclic voltammetry as well as amperometry. Cyclic voltammetry of artemisinin generated one prominent peak wave at -1.0 V and another, smaller one at -0.3 V vs Ag/AgCl reference electrode. The bulk electrolysis of artemisinin on a carbon electrode generated two other irreversible peak waves at around -0.7 and -0.1 V. The concentration of the products was dependent on the time of electrolysis. LC-MS was used …

Brush-Arm Star Polymer Imaging Agents And Uses Thereof, Jeremiah A. Johnson, Hung Vanthanh Nguyen, Andrzej Rajca

Department of Chemistry: Faculty Publications

Disclosed are methods, compositions, reagents, systems, and kits to prepare nitroxide-functionalized brush-arm star polymer organic radical contrast agent (BASP-ORCA) as well as compositions and uses thereof. Various embodiments show that BASP-ORCA display unprecedented per-nitrox-ide and per-molecule transverse relaxivities for organic radical contrast agents, exceptional stability, high water solubility, low in vitro and in vivo toxicity, and long blood compartment half-life. These materials have the potential to be adopted for tumor imaging using clinical high-field ¹H MRI techniques.

Indole Reverses Intrinsic Antibiotic Resistance By Activating A Novel Dual-Function Importer, Yan Wang, Tian Tian, Jingjing Zhang, Xin Jin, Huan Yue, Xiao-Hua Zhang, Liangcheng Du, Fan Bai

Department of Chemistry: Faculty Publications

Bacterial antibiotic resistance modulation by small signaling molecules is an emerging mechanism that has been increasingly reported in recent years. Several studies indicate that indole, an interkingdom signaling molecule, increases bacterial antibiotic resistance. However, the mechanism through which indole reduces antibiotic resistance is largely unknown. In this study, we demonstrated a novel mechanism for indole-mediated reversal of intrinsic antibiotic resistance in Lysobacter. This reversal was facilitated by a novel BtuD-associated dual-function importer that can transfer both vitamin B₁₂ and antibiotics. Indole stimulated btuD overexpression and promoted efficient absorption of extracellular vitamin B₁₂; meanwhile, the weak selectivity …

Rapid-Scan Epr And Imaging, Yilin Shi

Electronic Theses and Dissertations

EPR imaging at low frequency is a powerful tool to obtain important biological information in vivo in a non-invasive way. Properties of nitroxide and trityl radical imaging reagents have been studied. Developments in rapid scan imaging techniques are reported that improve efficiency of experiments and user-friendliness of software.

Relaxation and signal-to-noise ratio (S/N) in pulse experiments on trityl radicals were measured at frequencies between 400 MHz and 1.5 GHz. Relaxation time increases as the frequency increases and the radical concentration decreases. Since relaxation time is a sensitive and accurate measure of oxygen pressure, this study provides criteria for the selection …

In-Quest Of Biomarkers For Alzheimer’S Disease And Pharmacokinetic Profile Of Anticancer Agents Using Lc-Ms In Human Plasma, Chandana Mannem

ETD Archive

In this dissertation work, a semi-quantitative assay using a lipidomics approach and an absolute quantitative assay using liquid chromatography-mass spectrometry techniques were developed (LC-MS). In the lipidomics approach, ultra-high pressure liquid chromatography in tandem with quadrupole time of flight (UHPLC-QTOF) mass spectrometry was used to profile, compare and quantitate the human plasma lipids in Alzheimer’s disease subjects (AD) and normal cognitive controls (NCCs). The purpose of this study is to identify potential plasma lipid markers of AD and to explore the relationships between AD and lipid pathways in humans by using bioinformatic tools. The plasma samples of study subjects were …

The Periodical Winter 2019, Southern Adventist University

the Periodical – Chemistry Department Newsletter

Volume 6, issue 1 of the Periodical includes articles about Professor Loren Barnhurst's departure from the university, an alumni spotlight, general department news, at a pictorial listing of 2018-2019 Chemistry graduates.

Reactivity Of Molybdenum And Tungsten Sulfido Complexes With First-Series Transition Metals, Khalil Mudarmah

ETD Archive

Ammonium tetrathiomolybdate (ATTM) is an important compound in bioinorganic chemistry, with medicinal applications. Metal complexes of sulfur-containing ligands have been widely used as building block in biology and inorganic chemistry. This project aims to increase the number of Mo-S and W-S complexes that may contribute to fields such as bioinorganic and medicinal chemistry, by the preparation of heterometallic complexes containing both Mo or S and a metal of the first transition series. The homobimetallic complex anion salts (Et4N)2[Mo2(S)2(μ-S)2(edt)2] (1) and (Et4N)2[W2(S)2(μ-S)2(edt)2] (2) have been prepared from ATTM and ammonium tetrathiotungstate (ATTW) in order to start our work. The overnight treatment …

Development Of An Spr Method To Monitor The Chemical Interaction Of Dna With A Small Reactive Molecule: Peroxynitrite As An Example, Divya Sharma

ETD Archive

Peroxynitrite is an anion with the formula ONOO-. It is an unstable structural isomer of nitrate, NO3-. Although its conjugate acid (ONOOH) is highly reactive, it is quite relatively stable in basic solutions. Generation of peroxynitrite in-vivo occurs through the diffusion-controlled reaction between superoxide anion and nitric oxide free radical. It is a strong oxidizing and nitrating agent, and its formation has been correlated with many pathological conditions. Because of its oxidizing properties, peroxynitrite can damage a wide array of molecules in cells, including DNA and proteins. Reactions of peroxynitrite with DNA, proteins, and lipids, trigger a wide array of …

Development Of An Spr Method To Monitor The Chemical Interaction Of Dna With A Small Reactive Molecule: Peroxynitrite As An Example, Divya Sharma

ETD Archive

Peroxynitrite is an anion with the formula ONOO-. It is an unstable structural isomer of nitrate, NO3-. Although its conjugate acid (ONOOH) is highly reactive, it is quite relatively stable in basic solutions. Generation of peroxynitrite in-vivo occurs through the diffusion-controlled reaction between superoxide anion and nitric oxide free radical. It is a strong oxidizing and nitrating agent, and its formation has been correlated with many pathological conditions. Because of its oxidizing properties, peroxynitrite can damage a wide array of molecules in cells, including DNA and proteins. Reactions of peroxynitrite with DNA, proteins, and lipids, trigger a wide array of …

Liquid Chromatography - Mass Spectrometric Analysis Of Clinicallyand Pharmacologically Relevant Molecules, Raghavi Kakarla

ETD Archive

Liquid Chromatography-Mass Spectrometry is an advanced analytical technique that offers high sensitivity and specificity and has been increasingly used for analysis of a wide variety of compounds including clinically and pharmacologically relevant molecules. In this dissertation we describe qualitative and quantitative liquid chromatographic mass spectrometric methods to analyze both small molecules and larger macromolecules that provide useful insights into diagnosis and management of several diseases. An LCMS(/MS) analytical method includes extraction of analytes of interest from the matrix followed by liquid chromatographic separation and mass spectrometric detection. Chapter I describes pre-analytical workflows and sample pretreatment techniques and theories underlying LC-MS …

Synthesis Of Trisubstituted Indolizines From 2-Propargyloxypyridines, Colin T. Hartgerink, Jaimie E. Van De Burg, Carolyn E. Anderson

Summer Research

• Indolizines are a versatile heterocyclic core that occurs frequently in pharmaceutical leads for a variety of indications, including: anti-bacterial1 and anti-tumor agents,2 and targets for the treatment of Alzheimer’s disease,3 asthma,4 erectile dysfunction,5 and inflammation related to respiratory or cardiovascular disease.
• While evaluating the scope of a Au(I)-catalyzed rearrangement of 2- propargyloxypyridine 1, 7 substituted indolizine 4 was discovered as an unexpected by-product (Scheme 1). The structure of indolizine 4 was confirmed by NMR and Xray analysis. Investigations revealed that acetophenone, originally present as an impurity in the reaction, is a key reagent. The use of acetophenone as the solvent, …

Harnessing The Reactivity Of The N-Methyl Diaminobenzoyl Linker To Access C-Terminally Modified And Macrocyclic Peptides, Christine Arbour

Wayne State University Dissertations

This thesis describes the exploration of accessing C-terminally modified and macrocyclic peptides through N-acyl urea (MeNbz) displacement. Prior to this work, the diaminobenzoyl linker was used to access thioesters for native chemical ligation. Only solution-phase displacement of the N-acyl urea with thiol nucleophiles was previously reported.

The N-Me-diaminobenzoyl (MeDbz) linker was initially used to access C-terminal glycine esters, amides, and acids from a single peptide substrate. This led to the total synthesis of Conopressin G and two analogs. The propensity of the C-terminal cysteine residue to undergo epimerization was investigated using this strategy. After optimization, C-terminal cysteine esters, amides, and …

Influence Of Side Chain Conformation On The Mechanism(S) Of Glycosylation Reactions; Investigation Of Sialidation Reaction Mechanism(S) By Kinetic Studies, Harsha Chandhana Amarasekara

Wayne State University Dissertations

Glycosylation, being the key reaction of glycobiology and carbohydrate chemistry, demands robust and stereoselective glycosylation methods. The rational development of such methods necessitates knowledge of the glycosylation reaction mechanism and the factors influencing glycosylation reactions. The work discussed in this dissertation is focused on studying glycosylation reaction mechanisms and exploring the key factors influencing them.

Chapter one reviews the background to the research, starting with a brief introduction of the significance of carbohydrates as structural and energy-storage materials. The significance of cell surface carbohydrates and their roles in communication and related processes are discussed along with examples of their applications …

Nonadiabatic Dynamics: A Semiclassical Approach, Ruixi Wang

Wayne State University Dissertations

Nonadiabatic dynamics has been an essential part of quantum chemistry since the 1930’s. Nonadiabatic effects play a crucial role in photo-physical and photo-chemical reactions for both small and large molecules in both gas and condensed phases. Modeling dynamics of photoinduced reactions has been a new frontier of chemistry. Many dynamical phenomena, such as intersystem crossing, non-radiative relaxation, and charge energy transfer, require a nonadiabatic description which incorporates transitions between electronic states.

In Chapter 2, the property of scattering region in the semiclassical limit is investigated. We suggest that a nuclear wavepacket close enough to the conical intersection will propagate ballistically …

General Chemistry 2, Themis Lazaridis

Open Educational Resources

No abstract provided.

Split Probe Detection Of The Influenza A Virus For Improved Diagnostics In A Point Of Care System, Tamar Yishay

Honors Undergraduate Theses

A group of Influenza viruses, RNA containing viruses of the Orthomyxoviridae family, consists of Influenza virus types A-D and has been known to cause the Flu, a respiratory illness associated with numerous detrimental symptoms that can lead to death. Influenza A virus (IAV) is constantly changing and is capable of causing pandemics. Currently used diagnostic methods include virus culturing, immunoassays including rapid influenza detection tests (RIDTs), and molecular assays including those based on RT-PCR. Most of the methods can be only performed in the certified diagnostic laboratories equipped with sophisticated instrumentation and/or special biosafety facilities. The results using these methods …

Urinalysis Screening Of Drugs In Adulterated Samples Via Direct Analysis In Real Time -- High Resolution/ Mass Spectrometry (Dart-Hr/Ms), Bianca E. Olivieri

Honors Undergraduate Theses

Current screening methods for drug analysis with urine samples includes examination of the sample with an immunoassay. These methods are used to determine the concentration of drug metabolites contained within the sample prior to further confirmatory testing. Drug testing plays a crucial role in maintaining safe workplace environments and safety of individuals. However, a positive result can lead to heavy consequences for the employee including suspension or removal from the workplace. Therefore, a majority of individuals add commonly known products into the sample to evade detection by developing a false negative result. Although specimen integrity examinations are performed to identify …

Modification Of Bruker Amazon Etd And Solarix Mass Spectrometers Towards Infrared Multiple Photon Dissociation: Structural Characterization Of Modified Nucleosides, Lucas Ash Hamlow

Wayne State University Dissertations

Infrared ion spectroscopy has become an increasingly powerful tool for examining

the intrinsic structures of gas-phase ions. Infrared multiple photon dissociation (IRMPD)

action spectroscopy has been particularly successful. Several free electron laser (FEL)

facilities across the world have helped facilitate the growth of the IRMPD technique and

increasing interest has driven the development of more accessible IRMPD

instrumentation. The development of one such IRMPD instrumentation system is

described in this work, based around commercially available 3D quadrupole ion trap mass

spectrometers and Fourier-transform ion cyclotron resonance mass spectrometers.

The intrinsic gas-phase structures of nucleic acid monomers have been

extensively studied …

Synthesis And Study Of The Micellization Behavior Of A Dual Temperature- And Ph-Responsive Paa-B-Pnipam Block Copolymer, Ehsan Zarshenas Moghadam

Master's Theses and Doctoral Dissertations

Amphiphilic diblock copolymers are composed of hydrophilic and hydrophobic regions. When they are exposed to water, the hydrophobic blocks aggregate to form a hydrophobic core surrounded by hydrophilic regions outside to give a core-shell micelle. These micelles have many potential applications, such as a drug delivery system, surfactants, or nanoreactor. Many studies have been done to optimize the performance of these copolymers. In this thesis work, nine dual temperature- and pH-responsive poly(acrylic acid-block-N-isopropylacrylamide) (PAA-b-PNIPAM) diblock copolymers with different relative chain lengths of the hydrophobic and hydrophilic blocks were synthesized by reversible addition fragmentation chain transfer polymerization. The preliminary results showed …

Fluorescence Quenching-Based Mechanism For Determination Of Hypochlorite By Coumarin-Derived Sensors, Karolina Starzak, Arkadiusz Matwijczuk, Bernadette Creaven, Alicja Matwijczuk, Sławomir Wybraniec, Dariusz Karcz

Articles

A fluorescence quenching-based mechanism for the determination of hypochlorite was proposed based on spectroscopic and chromatographic studies on the hypochlorite-sensing potency of three structurally similar and highly fluorescent coumarins. The mode of action was found to rely upon a chlorination of the coumarin-based probes resulting from their reaction with sodium hypochlorite. Importantly, the formation of chlorinated derivatives was accompanied by a linear decrease in the fluorescence intensities of the probes tested. The results obtained suggest the applicability of a coumarin-dependent hypochlorite recognition mechanism for the detection of, as well as for quantitative determination of, hypochlorite species in vitro.

Understanding The Role Of Atg7 And Atg14 In Autophagy, Ronith Chakraborty

Senior Honors Theses and Projects

Autophagy is the process by which cytosolic components are trafficked to and degraded by the vacuole or lysosome. It plays a critical role in cellular health, aging, cancer, and neurodegenerative diseases. Atg7 and Atgl4 are enzymes required for the autophagic process in Saccharomyces cerevisiae. In this study, we hypothesized that Atg7 controls the size while Atg 14 controls the number of autophagosomes. Using western blotting, Pho8D.60 assay and transmission electron microscopy analysis, we found that Atg7 affects both the size and number of autophagosomes. In addition, we have created cells expressing various levels of Atgl4 using non-native promoters. In addition, …

N-Methyl Mesoporphyrin Ix As A Highly Selective Light-Up Probe For G-Quadruplex Dna, Ariana Yett , '21, Linda Yingqi Lin , '20, Dana Beseiso , '21, Joanne Miao , '22, Liliya A. Yatsunyk

Chemistry & Biochemistry Faculty Works

N-methyl mesoporphyrin IX (NMM) is a water-soluble, non-symmetric porphyrin with excellent optical properties and unparalleled selectivity for G-quadruplex (GQ) DNA. G-quadruplexes are non-canonical DNA structures formed by guanine-rich sequences. They are implicated in genomic stability, longevity, and cancer. The ability of NMM to selectively recognize GQ structures makes it a valuable scaffold for designing novel GQ binders. In this review, we survey the literature describing the GQ-binding properties of NMM as well as its wide utility in chemistry and biology. We start with the discovery of the GQ-binding properties of NMM and the development of NMM-binding aptamers. We then discuss …

Seven Coordinate Molybdenum And Tungsten Complexes Containing Tpm And Tpm Derivatives And The Impact Of Ligand Substitution On Nmr Chemical Shifts, Cole Seager

Undergraduate Honors Thesis Collection

A series of known and new seven coordinate molybdenum and tungsten complexes of tris(pyrazolyl)methane (Tpm) and substituted Tpm, [TpmM(CO)3X]+, have been synthesized. Depending on the identity of X, (bromo, iodo, hydrido) and the substitution of the Tpm ligand, substantial chemical shift differences are observed for the hydrogen on the central carbon of the Tpm ligand. Factors impacting the chemical shift of the hydrogen on the central carbon of the Tpm ligand, such as the electron donating ability of the Tpm ligand and the electronegativity of the additional ligand on the metal, will be discussed.