Reversing Interfacial Catalysis Of Ambipolar Wse2 Single Crystal,
2019
Sichuan University & Aarhus University
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 …
Automation Of Karl Fischer Titration For Animal Pharmaceutical Product Testing At Elanco Animal Health,
2019
DePauw University
Automation Of Karl Fischer Titration For Animal Pharmaceutical Product Testing At Elanco Animal Health, Elizabeth L. Grubbs
Annual Student Research Poster Session
Ever wonder what doing research looks like in the context of working in industry? This summer I had the opportunity to work at Elanco Animal Health, the world’s third largest animal pharmaceutical company (and growing!) I worked in the Quality Control laboratories where products are tested before they are sent out the door. I did research to automate a process that checks for the water content of various animal health products. The water content of these products is important for many reasons including expiration dates and FDA requirements. The process that I automated is called Karl Fischer titration and is …
Interaction Of A Platinum Triamine Complex Having A Seven-Membered Chelate Ring With N-Acetyl-Lmethionine And Guanosine 5'-Monophosphate,
2019
Western Kentucky University
Interaction Of A Platinum Triamine Complex Having A Seven-Membered Chelate Ring With N-Acetyl-Lmethionine And Guanosine 5'-Monophosphate, Jae Ko
Masters Theses & Specialist Projects
In the 1960s, Rosenberg and his colleagues confirmed the anti-cancer activity of cisplatin. Although cisplatin was capable of killing testicular cancer cells there were also serious side effects. It was necessary to find alternate ways of overcoming side effects, and soon many researchers have discovered novel platinum compounds that show similar reactivity. Recently, replacing one chloride group to a heterocyclic amine group showed significant cytotoxicity with a different binding activity than cisplatin. Previously in our lab, [Pt(Me5dien)(NO3)]+ and [Pt(Et2dien)Cl]+ have been synthesized and reacted with NAcetyl- L-methionine (N-AcMet) and Guanosine 5’-monophosphate (5’-GMP) showed unusual reactivity. Unlike most previously studied platinum …
Aerobic C-C And C-O Bond Formation Reactions Mediated By High-Valent Nickel Species.,
2019
Washington University in St. Louis
Aerobic C-C And C-O Bond Formation Reactions Mediated By High-Valent Nickel Species., Sofia Smith, Oriol Planas, Laura Gómez, Nigam Rath, Xavi Ribas, Liviu Mirica, Liviu Mirica
Chemistry & Biochemistry Faculty Works
Nickel complexes have been widely employed as catalysts in C–C and C–heteroatom bond formation reactions. While Ni(0), Ni(I), and Ni(II) intermediates are most relevant in these transformations, recently Ni(III) and Ni(IV) species have also been proposed to play a role in catalysis. Reported herein is the synthesis, detailed characterization, and reactivity of a series of Ni(II) and Ni(III) metallacycle complexes stabilized by tetradentate pyridinophane ligands with various N-substituents. Interestingly, while the oxidation of the Ni(II) complexes with various other oxidants led to exclusive C–C bond formation in very good yields, the use of O2 or H2O2 as oxidants led to …
Understanding Interactions Of Citropin 1.1 Analogues With Model Membranes And Their Influence On Biological Activity,
2019
University of Nebraska Medical Center
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,
2019
University of Nebraska-Lincoln
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 …
Systematic Optimization For Production Of The Anti-Mrsa Antibiotics Wap-8294a In An Engineered Strain Of Lysobacter Enzymogenes,
2019
Jiangnan University & University of Nebraska- Lincoln
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 …
Development Of A Screening Method For Drugs Of Abuse By Direct Analysis Of Dried Urine Spots Coupled To Mass Spectrometry,
2019
John Jay College of Criminal Justice
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 …
The Effects Of Active Site And Allosteric Residues On Catalysis And Inhibitor Selectivity In The Bacillus Stearothennophilus Dihydrofolate Reductase,
2019
Montclair State University
The Effects Of Active Site And Allosteric Residues On Catalysis And Inhibitor Selectivity In The Bacillus Stearothennophilus Dihydrofolate Reductase, Tyler Eck
Theses, Dissertations and Culminating Projects
In drug discovery, building a comprehensive picture of the binding events between a drug and its enzyme target can be useful, especially in the development of new drugs or predicting the effect of a drug on a similar target from the same protein family. It is well known that a drug's selectivity is influenced by its interactions with amino acid residues within the active site, but contributions from residues situated away from (distal to) the active site are less well understood. Using a novel predictive approach PAnPredictor that employs sequence alignments, we have previously predicted residue positions in the dihydrofolate …
Development Of Ni-Catalyzed Alkene Dicarbofunctionalization Reactions,
2019
University of New Mexico
Development Of Ni-Catalyzed Alkene Dicarbofunctionalization Reactions, Shekhar Kc
Chemistry and Chemical Biology ETDs
Alkenes serve as one of the most important feedstocks for organic synthesis, having two vicinal sites for bond formation. In alkenes, both vicinal sites can be functionalized with two reagents in a process commonly known as alkene difunctionalization, which results in the formation of two new bonds. A number of alkenes difunctionalization reactions, such as diamination, dioxygenation, carboamination and carbooxygenation, are known. However, difunctionalization of alkenes with two carbon-based entities, termed alkene dicarbofunctionalization, is relatively less common. Development of such a process could provide a powerful method to introduce two different carbon fragments across an alkene in a regioselective manner, …
Optimization Of Protein Entrapment In Affinity Microcolumns Using Hydrazide-Activated Silica And Glycogen As A Capping Agent,
2019
University of Nebraska-Lincoln
Optimization Of Protein Entrapment In Affinity Microcolumns Using Hydrazide-Activated Silica And Glycogen As A Capping Agent, John Vargas-Badilla, Saumen Poddar, Shiden Azaria, Chenhua Zhang, David S. Hage
David Hage Publications
Several approaches were compared for the entrapment of proteins within hydrazide-activated silica for use in affinity microcolumns and high performance affinity chromatography. Human serum albumin (HSA) and concanavalin A (Con A) were used as model proteins for this work. Items considered in this study included the role played by the solution volume, amount of added protein, and use of slurry vs. on-column entrapment on the levels of solute retention and extent of protein immobilization that could be obtained by means of entrapment. The levels of retention and protein immobilization were evaluated by injecting warfarin or 4-methylumbellipheryl α-D-mannopyranoside as solutes with …
Investigating Color Additive Molecules For Pharmaceutical And Cosmetic Applications: A Comparison Of Theoretical And Experimental Uv-Visible Absorbance Spectra In Tunable Solvents,
2019
Rowan University
Investigating Color Additive Molecules For Pharmaceutical And Cosmetic Applications: A Comparison Of Theoretical And Experimental Uv-Visible Absorbance Spectra In Tunable Solvents, Jacqueline Casey Mohen
Theses and Dissertations
Color additive molecules have widespread applications ranging from ingestible foods and pharmaceutics to non-ingestible cosmetics and other naturally or synthetically developed consumer products available worldwide. Certification for approved use of color additives varies globally; therefore, a feasible method to analyze existing color additives or to design novel color additive molecules with enhanced or otherwise desired physicochemical properties (such as hue) is in high demand for universal adoption. The studies herein provide sufficient proof that density functional theory and time-dependent density functional theory serve as effective predictive modeling techniques for generating theoretical maximum absorbance spectral peak responsivity for a single color …
Integration Of Random Forest Classifiers And Deep Convolutional Neural Networks For Classification And Biomolecular Modeling Of Cancer Driver Mutations,
2019
Chapman University
Integration Of Random Forest Classifiers And Deep Convolutional Neural Networks For Classification And Biomolecular Modeling Of Cancer Driver Mutations, Steve Agajanian, Odeyemi Oluyemi, Gennady M. Verkhivker
Mathematics, Physics, and Computer Science Faculty Articles and Research
Development of machine learning solutions for prediction of functional and clinical significance of cancer driver genes and mutations are paramount in modern biomedical research and have gained a significant momentum in a recent decade. In this work, we integrate different machine learning approaches, including tree based methods, random forest and gradient boosted tree (GBT) classifiers along with deep convolutional neural networks (CNN) for prediction of cancer driver mutations in the genomic datasets. The feasibility of CNN in using raw nucleotide sequences for classification of cancer driver mutations was initially explored by employing label encoding, one hot encoding, and embedding to …
Determination Of Anxiolytic And Antidepressant Medicines In New York City Wastewater Samples,
2019
CUNY John Jay College
Determination Of Anxiolytic And Antidepressant Medicines In New York City Wastewater Samples, Jasmine J. Gayle
Student Theses
Wastewater-based epidemiology (WBE) provides information about a population’s exposure to certain chemical agents, such as drugs of abuse and medicines, by the analysis of human biomarkers, also known as excretion products, in wastewater samples. Although this is a growing field worldwide, mainly in Europe, Oceania, and Asia, limited data from the US are currently available. We developed and validated an analytical method to quantitatively and qualitatively determine the presence of commonly prescribed drugs to treat anxiety (alprazolam, buspirone, clonazepam, lorazepam, and propranolol) and depression (bupropion, citalopram, clomipramine, duloxetine, fluoxetine, imipramine, paroxetine, sertraline, and venlafaxine) in wastewater using liquid chromatography tandem …
Investigations Of The Mechanism Of Action For Lung Cancer Cell Death By A 4-Trifluoromethoxy Substituted Chalcone,
2019
Bellarmine University
Investigations Of The Mechanism Of Action For Lung Cancer Cell Death By A 4-Trifluoromethoxy Substituted Chalcone, Trevor M. Stantliff
Undergraduate Theses
Chalcones are a diphenyl compound that serves as a natural precursor to flavonoids in plants. Chalcones have been shown to have anticancer and antimicrobial activities. Chemoprevention activity of chalcones are of high interest in medicinal chemistry because of the simple laboratory synthesis and modification via Claisen-Schmidt condensation. Previously this lab created and screened a library of synthetic chalcones against A549 lung adenocarcinoma cell line for antiproliferation properties. We identified a strong drug candidate (4-trifluoromethoxy substituted chalcone) for A549 growth inhibition. However, the cause of inhibition by the substituted chalcone remains to be identified We began to explore the mechanism of …
Manipulation Of Noncovalent Interactions For The Synthesis And Use Of Natural Product Synthons,
2019
University of Southern Mississippi
Manipulation Of Noncovalent Interactions For The Synthesis And Use Of Natural Product Synthons, Alison P. Hart
Dissertations
Natural products are widely used in the pharmaceutical industry, in agriculture, and as specialty chemicals. Methodology development focuses on optimizing the key organic reactions to access these natural products while trying to limit the overall number of synthetic steps. Key bond forming strategies are sought to provide new ways to address carbon-carbon or carbon-heteroatom bonds. The advancement of new asymmetric reactions to generate enantiopure products from achiral starting materials is a vital area of research. The objectives addressed in this dissertation include: 1) the development of a general reductive conversion of esters to ethers with a broad substrate scope accessing …
The Characterization Of A New Metabolite From A Trichodesmium Bloom,
2019
University of Rhode Island
The Characterization Of A New Metabolite From A Trichodesmium Bloom, Kelly M. Mcmanus
Senior Honors Projects
Our laboratory has been investigating blooms of Trichodesmium, a genus of ecologically important, nitrogen-fixing cyanobacteria, collected from Padre Island in the Gulf of Mexico. Trichodesmium species are an underexplored biological source of cyanobacteria – a taxa that has been shown to produce chemically diverse secondary metabolites. With our focus on the isolation and structure characterization of new bioactive marine natural products, our research group has discovered over 25 new-to-science compounds over the past three years from these blooms. UV and mass spectrometry-guided isolation of Trichodesmium chromatography fractions were utilized to isolate a new metabolite. Isolation of this metabolite was …
The Use Of Heterocycles As Important Structures In Medicinal Chemistry,
2019
University of Southern Mississippi
The Use Of Heterocycles As Important Structures In Medicinal Chemistry, Sayre Weast
Honors Theses
Heterocycles have many applications in the discipline of medicinal chemistry. These structures are found in various natural products with relevant biological activity. Our research group, in collaboration with two others, is particularly interested in one heterocycle, quinoline, as a scaffold for HIV-1 integrase inhibitors. A synthetic route has been developed to produce a derivatized structure on small scale. One goal of this thesis was to expand the scale of this route to provide increased quantities of the quinoline scaffold. Procedures were adapted to accommodate the increase in scale to convert commercially available anthranilic acids to quinolines via the isatoic anhydride. …
Preparation Of Enantioenriched Alkyltin Species And Their Application In Stereospecific Transformations,
2019
CUNY Graduate Center
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 …
A Pretargeted Spect Imaging Strategy Employing Technetium-99m Based On Bioorthogonal Diels-Alder Click Chemistry,
2019
CUNY Graduate Center
A Pretargeted Spect Imaging Strategy Employing Technetium-99m Based On Bioorthogonal Diels-Alder Click Chemistry, Justin H. Walsh
Dissertations, Theses, and Capstone Projects
A series of related N3S 99mTc-peptide complexes were synthesized and tested for use in pretargeting SPECT imaging that utilizes the bioorthogonal Diels-Alder click reaction between tetrazine (Tz) and transcyclooctene (TCO). The objective was to optimize the excretory pathways of the 99mTc-peptide complexes for maximum tumor targeting with the in vivo “click” and minimum non-target uptake. The 99mTc–tetrazine constructs were prepared by reaction of 99mTc-peptide complexes (99mTc-FKC, 99mTc-FKCR, 99mTc-DKC, and 99mTc-SKC) with Tz-NHS or Tz-PEG5-NHS to form 99mTc FK(Tz)C, 99mTc-FK(PEG5-Tz)CR, 99mTc-DK(PEG5-Tz)C, …
