Chemistry Commons^™

Evaluation Of Tumor Necrosis Factor Alpha In Sleep-Deprived Menopausal- Induced Rats And The Impact On Bone Health, Nicole Ellsworth, Dwight Curry Iii, Cj Deleon, Frank Frisch

Student Scholar Symposium Abstracts and Posters

Post-menopausal osteoporosis as a consequence of estrogen depletion is a growing concern for women in the United States. As more women take on executive positions and experience sleep deprivation, there is the potential for up regulation of pro-inflammatory cytokines, such as tumor necrosis factor alpha. It follows that the homeostatic imbalance of osteoclastic and osteoblastic activity leads to a greater risk of disease. Bisphosphonates generally, and Zolendronate specifically works by decreasing the number of osteoclasts. This current study investigated the impact of Zolendronate on the concentrations of tumor necrosis factor alpha-type (TNFɑ) in 32 ovariectomized Wistar rats. Throughout a five …

Characterization Of The Dimerization Domains On The Mannose-6-Phosphate/Insulin-Like Growth Factor Ii Receptor, Tyler Degener

Theses/Capstones/Creative Projects

The mannose-6-phosphate/insulin-like growth factor II (M6P/IGF2) receptor is a transmembrane protein known to sequester growth factors from the extracellular matrix. This behavior suggests a mechanism of tumor suppression. Structurally, the receptor’s extracellular region is segmented into 15 homologous repeats, which are divided further into 5 triplet domains, labelled 1-3, 4-6, 7-9, 10-12, and 13-15. What is notable about the triplets is their propensity to form dimers with triplets on a second M6P/IGF2 receptor. In fact, previous studies indicate that this protein functions optimally when dimerized. Thus, the purpose of this experiment is to characterize these domain interactions. Using a urea …

Amphiphilic Block Copolymer Micelles In Selective Solvents: The Effect Of Solvent Selectivity On Micelle Formation, Labeesh Kumar, Andriy Horechyy, Eva Bittrich, Bhanu Nandan, Petra Uhlmann, Andreas Fery

Department of Chemistry: Faculty Publications

We investigated the micellar behavior of a series of asymmetric polystyrene-block-poly (4-vinylpyridine) (PS-b-P4VP) block copolymers in different P4VP-selective alcoholic solvents. The micellar behavior was further correlated with the spectroscopic ellipsometry results obtained on swelling of PS and P4VP polymer films in the corresponding solvent vapors. The time-resolved (in situ) dynamic light scattering (DLS) measurements, in combination with (ex situ) electron microscopy imaging, revealed information about the aggregation state of PS-b-P4VP BCP in different alcohols and the effect of heat treatment. The ellipsometry measurements allowed us to estimate the difference in solvent selectivity toward PS/P4VP pair. Both DLS and ellipsometric studies …

The Potential Of Radium-224 As A Tracer Of Timescales Of Gulf Of Mexico Crude Oil Exposure To The Marine Environment, Matthew T. Kurpiel

Electronic Theses and Dissertations

Petroleum pollution in the marine environment can be deleterious to coastal and marine ecosystems and can have sustained effects for years. While oil slicks on the surface of the ocean are tracked with relative ease using satellite-based technology, deep sea, neutrally-buoyant hydrocarbon plumes remain exceedingly difficult to track. We provide evidence for the utility of Ra-224 as a potential hydrocarbon tracer to determine the marine exposure time of crude oil. We employed time course incubations to constrain a time dependent Ra-224 release signature and tested a variety of timescales, temporal resolutions, oil sources, seawater, and experimental treatments to determine potential …

Root Cause Analysis And Method Development Of Calorimetry Experiments, Anya M. Deaton, Lydia R. Deaton, John M. Farrar Dr.

Posters-at-the-Capitol

First year chemistry students learn a broad range of concepts that are also proven out in the lab environment. These concepts are a basis for a solid foundation for future chemistry learning. When the lab experiments don’t produce the expected results, students understanding in these concepts diminish and overall confidence and grades suffer. Our project details the root cause analysis and subsequent method development work for two experiments related to calorimetry; heat of solution and freezing point depression. The team sought to refine these experiments after finding that many of the students were unable to generate the expected results for …

Medium-Dependent Antibacterial Properties And Bacterial Filtration Ability Of Reduced Graphene Oxide, Alexander Gusev, Olga Zakharova, Dmitry S. Muratov, Nataliia S. Vorobeva, Mamun Sarker, Iaroslav Rybkin, Daniil Bratashov, Evgeny Kolesnikov, Aleš Lapanje, Denis V. Kuznetsov, Alexander Sinitskii

Department of Chemistry: Faculty Publications

Toxicity of reduced graphene oxide (rGO) has been a topic of multiple studies and was shown to depend on a variety of characteristics of rGO and biological objects of interest. In this paper, we demonstrate that when studying the same dispersions of rGO and fluorescent Escherichia coli (E. coli) bacteria, the outcome of nanotoxicity experiments also depends on the type of culture medium. We show that rGO inhibits the growth of bacteria in a nutrition medium but shows little eect on the behavior of E. coli in a physiological saline solution. The observed eects of rGO on E. coli in …

Reversing Interfacial Catalysis Of Ambipolar Wse2 Single Crystal, Zegao Wang, Hong-Hui Wu, Qiang Li, Flemming Besenbacher, Yanrong Li, Xiao Cheng Zeng, Mingdong Dong

Department of Chemistry: Faculty Publications

An improved understanding of the origin of the electrocatalytic activity is of importance to the rational design of highly efficient electrocatalysts for the hydrogen evolution reaction. Here, an ambipolar single-crystal tungsten diselenide (WSe2) semiconductor is employed as a model system where the conductance and carrier of WSe2 can be individually tuned by external electric fields. The field-tuned electrochemical microcell is fabricated based on the single-crystal WSe2 and the catalytic activity of the WSe2 microcell is measured versus the external electric field. Results show that WSe2 with electrons serving as the dominant carrier yields much higher activity than WSe2 with holes …

It's Elementary: A Review Of Forensic Analysis Techniques Of Inorganic Components Of Explosives, Sadie Schultz

Chemistry & Biochemistry Student Projects

No abstract provided.

Antioxidants And Beta-Carotene: A General Overview, A Research History, And Modern Scholarship, James Joseph Dickman Iv

Chemistry & Biochemistry Student Projects

This paper seeks to provide a cursory overview of oxidative stress and the accompanying biomolecules which are used to combat it. From there, the paper will provide a somewhat comprehensive list of major historical discoveries regarding antioxidant molecules, in particular beta-carotene. After this, an overview of more modern scholarship on the issue of these molecule’s antioxidant properties specific (from the 1970s onward) will be discussed up to modern times. The paper will conclude with an in depth look at the modern scholarship on beta-carotene that was performed here at Taylor University.

Bone Regeneration Via Inorganic/Organic Compatibility In A Newly Synthesized Hydrogel: Nhap-Bmp-2, Hannah Ewing

Chemistry & Biochemistry Student Projects

In this paper, nHAp-BMP-2 hydrogel is carefully synthesized in order to optimize the organic and inorganic compatibility which induces osteogenesis—the formation of new bone. This new method is a novel development within the medical field, giving more hope to those suffering from traumatic bone injuries. A drawback with using hydrogels is the difficulty of controlling peptide release in the affected areas. Too quick of a release alarms the human inflammatory response resulting in more substantial injury and an even prolonged recovery time. On the other hand, if the peptides that promote bioactivity are released too slowly, the bone will not …

Quantum Chemical Methods: Its History And Future, Erica Mitchell

Chemistry & Biochemistry Student Projects

No abstract provided.

Significance And Implications Of Vitamin B-12 Reaction Shema- Eth Zurich Variant: Mechanisms And Insights, David Joshua Ferguson

Chemistry & Biochemistry Student Projects

This is an undergraduate chemistry thesis document. This involves a discussion of the mechanisms and overall reactions involved in the total synthesis of vitamin B-12.

The History And Development Of Identification: Rediscovery And Application Of Egyptian Blue, Bailee Allen

Chemistry & Biochemistry Student Projects

The use of fingerprints as a form of identification in criminal cases has become a common method of conviction within the criminal justice system. However, with the recent rise in the number of people wrongly convicted, the typical sources of evidence have come into question about their reliability. Multiple common drawbacks found when using fingerprints dusting to obtain prints from crime scenes has led to researchers looking for more efficient ways to collect them that maintain high sensitivity and contrast. These are the two aspects that create the largest problem, especially on highly reflective and highly patterned surfaces. The discovery …

The Chemistry Of Jellybeans, Andrew Carter

Chemistry & Biochemistry Student Projects

Jellybeans are an amazing work of chemistry. In my paper, I outline the history and science behind this little candy. My paper describes taste receptors, molecular structure, and the analytical chemistry that help to make flavor science an interesting field of work.

Metallodrugs And Their Various Impacts On Disorders And Diseases, Paige Wagner

Chemistry & Biochemistry Student Projects

No abstract provided.

Time-Resolved Observation Of Transient Precursor State Of Co On Ru(0001) Using Carbon K-Edge Spectroscopy, Hsin-Yi Wang, Simon Schreck, Matthew Weston, Hirohito Ogasawara, Jerry Larue, Fivos Perakis, Martina Dell'angela, Flavio Capotondi, Luca Giannessi, Emanuele Pedersoli, Denys Naumenko, Ivaylo Nikolov, Lorenzo Raimondi, Carlo Spezzani, Martin Beye, Filippo Cavalca, Boyang Liu, Jörgen Gladh, Sergey Koroidov, Piter S. Miedema, Roberto Costantini, Lars G. M. Pettersson, Anders Nilsson

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The transient dynamics of carbon monoxide (CO) molecules on a Ru(0001) surface following femtosecond optical laser pump excitation has been studied by monitoring changes in the unoccupied electronic structure using an ultrafast X-ray free-electron laser (FEL) probe. The particular symmetry of perpendicularly chemisorbed CO on the surface is exploited to investigate how the molecular orientation changes with time by varying the polarization of the FEL pulses. The time evolution of spectral features corresponding to the desorption precursor state was well distinguished due to the narrow line-width of the C K-edge in the X-ray absorption (XA) spectrum, illustrating that CO molecules …

Understanding Interactions Of Citropin 1.1 Analogues With Model Membranes And Their Influence On Biological Activity, Nathalia Rodrigues De Almeida, Jonathan Catazaro, Maddeboina Krishnaiah, Yashpal Singh Chhonker, Daryl J. Murry, Robert Powers, Martin Conda-Sheridan

Department of Chemistry: Faculty Publications

The rapid emergence of resistant bacterial strains has made the search for new antibacterial agents an endeavor of paramount importance. Cationic antimicrobial peptides (AMPs) have the ability to kill resistant pathogens while diminishing the development of resistance. Citropin 1.1 (Cit 1.1) is an AMP effective against a broad range of pathogens. 20 analogues of Cit 1.1 were prepared to understand how sequence variations lead to changes in structure and biological activity. Various analogues exhibited an increased antimicrobial activity relative to Cit 1.1. The two most promising, AMP-016 (W3F) and AMP-017 (W3F, D4R, K7R) presented a 2- to 8-fold increase in …

A Panel Of Protein Kinase Chemosensors Distinguishes Different Types Of Fatty Liver Disease, Jon R. Beck, Fatima Cabral, Karuna Rasineni, Carol A. Casey, Edward N. Harris, Cliff I. Stains

Department of Chemistry: Faculty Publications

The worldwide incidence of fatty liver disease continues to rise, which may account for concurrent increases in the frequencies of more aggressive liver ailments. Given the existence of histologically identical fatty liver disease subtypes, there is a critical need for the identification of methods that can classify disease and potentially predict progression. Herein, we show that a panel of protein kinase chemosensors can distinguish fatty liver disease subtypes. These direct activity measurements highlight distinct differences between histologically identical fatty liver diseases arising from diets rich in fat versus alcohol and identify a previously unreported decrease in p38α activity associated with …

Hidden Bias In The Dud-E Dataset Leads To Misleading Performance Of Deep Learning In Structure-Based Virtual Screening, Lieyang Chen, Anthony Cruz, Steven Ramsey, Callum J. Dickson, Jose S. Duca, Viktor Hornak, David R. Koes, Tom Kurtzman

Publications and Research

Recently much effort has been invested in using convolutional neural network (CNN) models trained on 3D structural images of protein-ligand complexes to distinguish binding from non-binding ligands for virtual screening. However, the dearth of reliable protein-ligand x-ray structures and binding affinity data has required the use of constructed datasets for the training and evaluation of CNN molecular recognition models. Here, we outline various sources of bias in one such widely-used dataset, the Directory of Useful Decoys: Enhanced (DUDE). We have constructed and performed tests to investigate whether CNN models developed using DUD-E are properly learning the underlying physics of molecular …

Systematic Optimization For Production Of The Anti-Mrsa Antibiotics Wap-8294a In An Engineered Strain Of Lysobacter Enzymogenes, Xusheng Chen, Shanren Li, Lingjun Yu, Amanda Miller, Liangcheng Du

Department of Chemistry: Faculty Publications

WAP-8294A is a group of cyclic lipodepsipeptides and considered as the first-in-class new chemical entity with potent activity against methicillin-resistant Staphylococcus aureus. One of the roadblocks in developing the WAP-8294A antibiotics is the very low yield in Lysobacter. Here, we carried out a systematic investigation of the nutritional and environmental conditions in an engineered L. enzymogenes strain for the optimal production of WAP-8294A. We developed an activity-based simple method for quick screening of various factors, which enabled us to optimize the culture conditions. With the method, we were able to improve the WAP-8294A yield by 10-fold in small-scale cultures and …

The Roundtable Of Scientific Communication: From Classroom To Course Creation, Back To Classroom And Beyond, Sean P. Hickey

LSU New Orleans Theses and Dissertations

This research encompasses many aspects of chemical education research including curriculum and pedagogical changes to the freshman and sophomore courses. Curriculum changes included the addition of recitations to the general chemistry and organic chemistry lectures and the creation of four new classes, CHEM 1001, 1002, 3091, and 3092. The addition of recitations was not limited to but was focused on improving DFW rates for these courses.

CHEM 3091 and 3092 are chemistry internship and undergraduate teaching assistant classes. These courses were necessary to offer outside internship opportunities and training for undergraduate teaching assistants, respectively. CHEM 1001 and 1002 are chemistry …

Development Of A Screening Method For Drugs Of Abuse By Direct Analysis Of Dried Urine Spots Coupled To Mass Spectrometry, Melanie Goldstein

Student Theses

Fast and easy screening procedures are essential in any forensic toxicology laboratory to differentiate negative samples from presumptive positive cases. Immunoassay techniques, such as enzyme multiplied immunoassay technique (EMIT), are routinely employed as screening procedures. However, these techniques lack specificity (only differentiate group of drugs and not individual compounds) and it is difficult to add new compounds to the panel. Direct analysis of dried urine spots (DUS) by mass spectrometry (MS) offers a novel strategy to overcome these issues. DUS offer an improved storage alternative for biological samples, reducing costs and space requirements. In this work, an original method to …

Indole-3-Glycerol Phosphate Synthase Ligand Binding Interactions, Oshane Thomas

Theses, Dissertations and Culminating Projects

Indole-3-glycerol phosphate synthase (IGPS) catalyzes the irreversible ring closure of 1-(ocarboxyphenylamino)- 1-deoxyribulose 5- phosphate (CdRP) into indole-3-glycerol phosphate (IGP) during the fourth step in tryptophan biosynthesis. Analysis of the crystal structure of IGPS from Mycobacterium tuberculosis (MtIGPS) hinted the importance of Lys119 for binding or catalysis. Lys110 from sulfolobus sulfataricus IGPS (ssIGPS) that aligns with Lys119 from MtIGPS, was proposed to be a general acid for the proton transfer that initiates the ring closure and decarboxylation of CdRP. To study the importance of Lys119 in the chemical mechanism for MtIGPS, an amino acid change was made at this position to …

Using Molecular Dynamics To Study Qs21 Interactions And Penetration Of Lipid-Cholesterol Bilayers, Sarai Guerrero, Mikko Karttunen

Western Research Forum

Saponins have been used as adjuvant agents for decades in vaccines and therapies, but none are as well studied or heavily used as QS-21. This achievement is notwithstanding the fact that QS-21 usage is limited by its stability, toxicity, and scarcity. These shortcomings have only pushed researchers to develop and experiment with artificial recreations of the saponin to harness its unique benefits. A considerable number of research hours have been poured into this topic, but like QS-21 there is a shortcoming here as well. The number of articles that look at QS-21 interactions with the bilayer or the conditions under …

Obscurin Is A Semi-Flexible Molecule In Solution, Jacob Whitley

Senior Honors Projects, 2010-2019

Obscurin, a giant modular cytoskeletal protein, is comprised mostly of tandem immunoglobulin-like (Ig-like) domains. This architecture allows obscurin to connect distal targets within the cell. The linkers connecting the Ig domains are usually short (3-4 residues). The physical effect arising from these short linkers is not known; such linkers may lead to a stiff elongated molecule or, conversely, may lead to a more compact and dynamic structure. In an effort to better understand how linkers affect obscurin flexibility, and to better understand the physical underpinnings of this flexibility, here we study the structure and dynamics of four representative sets of …

Using Green Emitting Ph-Responsive Nanogels To Report Environmental Changes Within Hydrogels: A Nanoprobe For Versatile Sensing, Mingning Zhu, Dongdong Lu, Shanglin Wu, Qing Lian, Wenkai Wang, L. Andrew Lyon, Weiguang Wang, Paulo Bártolo, Brian R. Saunders

Engineering Faculty Articles and Research

Remotely reporting the local environment within hydrogels using inexpensive laboratory techniques has excellent potential to improve our understanding of the nanometer-scale changes that cause macroscopic swelling or deswelling. Whilst photoluminescence (PL) spectroscopy is a popular method for such studies this approach commonly requires bespoke and time-consuming synthesis to attach fluorophores which may leave toxic residues. A promising and more versatile alternative is to use a pre-formed nanogel probe that contains a donor/acceptor pair and then “dope” that into the gel during gel assembly. Here, we introduce green-emitting methacrylic acid-based nanogel probe particles and use them to report the local environment …

Unravel Allostery Mechanism Through Molecular Dynamic Simulations With Machine Learning Approaches, Hongyu Zhou

Chemistry Theses and Dissertations

Allostery is referred to as protein function changes due to external perturbations, and ubiquitous in the living cells. Investigation of the allosteric mechanism is essential for developing drugs or assisting protein engineering. Recently, the population shift model has been proposed to explain the allosteric mechanism. This model emphasizes the importance of conformational distribution in the allostery. In the past several years, I have been continuously working on developing computational methods to explore and quantify protein allostery mechanism. By fully utilizing protein simulation results, several machine learning related methods have been applied to protein systems to investigate the underlying conformational changes …

The Forensic Analysis Of Skin-Safe Stamp Pad Inks, Swetha Rajagopal

Student Theses

Skin-safe stamp pad inks are currently being used at locations such as clubs, zoos and other events with the purpose of stamping individuals that visit the location. This is done in an attempt to monitor the number and activity of visitors. Ink manufacturing companies generally tend to experiment with a number of different combinations of the different components of ink, in order to obtain desirable properties. The combinations are usually proprietary and that very nature of the inks ends up making them, possibly unique and individual. The analysis, identification and possible individualization of the chemical composition of these inks could …

Preparation Of Enantioenriched Alkyltin Species And Their Application In Stereospecific Transformations, Glenn O. Ralph

Dissertations, Theses, and Capstone Projects

Organometallic reagents containing the tin-carbon bond are used extensively in modern synthetic chemistry for the formation of new bonds to carbon. Over recent decades, transition metal catalyzed cross coupling reactions between two C(sp²) centers have been widely developed. However, the introduction of a C(sp³) center complicates the catalytic cycle, and opens unproductive chemical pathways which lead to isomerization, elimination, and racemization. Our lab has developed a modified-Stille reaction to combat the deleterious effects of β-hydride elimination. Our protocol enables unactivated 2° alkyl organotin nucleophiles to undergo efficient cross coupling reactions with C(sp²) electrophiles, avoiding …

The Effects Of Ph On The Kinetics Of The Follow-Up Reaction Of Dopamine O-Quinone, Cyril Fong, Ziming Dong

Creative Activity and Research Day - CARD

The electrochemical studies of dopamine have been conducted for many years due to dopamine’s importance as a neurotransmitter and its function in daily life for individuals. Dopamine undergoes electrochemical redox reactions in which the different products can be detected by cyclic voltammetry.³ The focus of the experiments was to determine the pH range at which dopamine o-quinone would undergo cyclization as well as the relationship between the rate of cyclization as pH in the physiological range. The measurements were taken using a gold working electrode vs. a Ag/AgCl (1 M KCl) reference electrode. It was observed that the peaks …