Digital Commons Network^™

Peroxide Sensing Using Nitrogen-Doped And Platinum Nanoparticle-Modified Screen-Printed Carbon Electrodes, Chidiebere Ogbu

Electronic Theses and Dissertations

Nitrogen-doped carbon materials have garnered much interest due to their abilities to behave as electrocatalysts for reactions important in energy production (oxygen reduction) and biosensing (hydrogen peroxide reduction). Here, we demonstrate fabrication methods and determine electrocatalytic properties of nitrogen-doped screen-printed carbon (N-SPCE) electrodes. Nitrogen doping of graphite was achieved through a simple soft-nitriding technique which was then used in lab-formulated screen-printing inks to prepare N-SPCEs. N-SPCEs displayed good electrocatalytic activity, reproducibility and long term stability towards the electrochemical reduction of hydrogen peroxide. N-SPCEs exhibited a wide linear range (20 µM to 5.3 mM), reasonable limit of detection of 2.5 µM, …

Simple Photochemical Reduction Of Carbon Dioxide To Formate, Ovuokenye Omadoko

Electronic Theses and Dissertations

There is a need to develop techniques for conversion of carbon dioxide to other useful products such as methanol, formaldehyde, formic acid, formate, methane, and hydrocarbons. Carbon dioxide can be converted into these products using different methods such as photochemical, electrochemical, thermochemical and hydrogenation by bacteria. Formate is of interest due to its wide industrial applications which include it’s use in direct liquid fuel cells, as an additive in pyrolysis vapors, a precursor for biological fuels, and it is a key intermediate in methanogenesis breaking down complex organic compounds. In this work, conversion of carbon dioxide to formate was accomplished …

Electronic Transmutation: An Aid For The Rational Design Of New Chemical Materials Using The Knowledge Of Bonding And Structure Of Neighboring Elements, Katie A. Lundell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Everything in the universe is made up of elements from the periodic table. Each element has its own role that it plays in the formation of things it makes up. For instance, pencil lead is graphite. A series of honeycomb-like structures made up of carbon stacked on top of one another. Carbon’s neighbor to the left, boron doesn’t like to form such stacked honeycomb-like structures. But, what if there was a way to make boron act like carbon so it did like to form such structures? That question is the basis of the electronic transmutation concept presented in this dissertation. …

Synthesis And Biological Studies Of Amphiphilic Compounds Derived From Saccharides And Aminoglycosides, Madher N. Alfindee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Adjacent cells communicate through gap junctions (GJs). These GJs are formed by head to head docking of two hemichannels (HCs) from two adjacent cells. HCs are connexin hexamer proteins. Connexin mutation is the most frequent cause of childhood hearing loss. This hearing impairment affects 2 in every 2000 children. Inhibition of the HCs might be the key factor to treat such disorders. A library of amphiphilic kanamycins was synthesized to be tested as HC inhibitors. These compounds showed excellent inhibition activity in comparison with the parent compound (kanamycin A) with less toxicity.

A library of monosaccharide esters with varying carbon …

Phosphonate-Directed Catalytic Asymmetric Hydroboration: Synthesis Of Functionalized Chiral Secondary And Tertiary Boronic Esters And Mechanistic Insights, Suman Chakrabarty

Department of Chemistry: Dissertations, Theses, and Student Research

Over the past 30 years, catalytic asymmetric hydroboration (CAHB) of alkenes has emerged as a leading methodology to access chiral primary and secondary boronic esters. However, it wasn’t until 2015 that directed-CAHB was for the first time shown to efficiently access chiral tertiary boronic esters. The latter are excellent precursors to synthetically challenging structural motifs such as chiral tertiary alcohols, carbinamines and all-carbon quaternary stereocenters via stereospecific C-B bond substitutions. This dissertation focuses on phosphonate-directed CAHB of diverse alkene substrates, including challenging stereodefined trisubstituted alkenes, to efficiently access multifunctional chiral secondary and tertiary boronic esters. Mechanistic insights obtained via deuterium …

Self-Assembly, Integration, Characterizations And Applications Of Plasmonic And Excitonic Nanomaterials, Bijesh Kafle

Chemistry and Chemical Biology ETDs

Plasmon on metal nanoparticles can efficiently confine, amplify light at the nanoscale. This property is beneficial for different applications such as harvesting energy of the broad solar spectrum, highly sensitive spectroscopy, photocatalysis, and many other optoelectronic applications. For plasmonic applications, it is necessary to understand the fundamental physical properties of the individual, coupled plasmonic nanomaterials, and their interaction with the surrounding environment, which is not fully understood yet. In this dissertation, the chemical and optical interaction in plasmonic interfaces has been investigated. Plasmon-enhanced photochemistry of p-aminothiophenol as a model molecule is investigated using highly sensitive surface-enhanced Raman spectroscopy (SERS). The …

Stereodynamical Control Of A Quantum Scattering Resonance In Cold Molecular Collisions, Pablo G. Jambrina, James F.E. Croft, Hua Guo, Mark Brouard, Balakrishnan Naduvalath, F. Javier Aoiz

Chemistry and Biochemistry Faculty Research

Cold collisions of light molecules are often dominated by a single partial wave resonance. For the rotational quenching of HD (v=1, j=2) by collisions with ground state para-H2, the process is dominated by a single L=2 partial wave resonance centered around 0.1 K. Here, we show that this resonance can be switched on or off simply by appropriate alignment of the HD rotational angular momentum relative to the initial velocity vector, thereby enabling complete control of the collision outcome.

Small Angle X-Ray Scattering Study Of Conformational Changes In Steroid Responsive Activator (Sra) Rna Upon Binding With Suppressor Protein Sharp, Diane Diatta

Master of Science in Chemical Sciences Theses

ABSTRACT

Differentiation and proliferation are known to be influenced by steroid stimulation. The steroid receptor activator (SRA) RNA is a large RNA transcript indicated to be an epigenetic regulatory component in the steroid receptor coactivator-1 (SRC-1) acetyltransferase complex. It is needed for a response to steroid hormones by tumor cells. However, this activity is hindered by suppressive RNA binding proteins like the SMRT/HDAC1-associated repressor protein (SHARP), which binds the STR7 domain of SRA RNA through its four RNA recognition motifs (RRMs); it is not fully understood how SHARP executes this role as there are no SRA RNA-SHARP structures available for …

60th Annual Rocky Mountain Conference On Magnetic Resonance

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 60th annual meeting of the Rocky Mountain Conference on Magnetic Resonance, co-endorsed by the Colorado Section of the American Chemical Society and the Society for Applied Spectroscopy. Held in Denver, Colorado, July 21-25, 2019.

The Chemistry And Biology Of Cyclophostin, The Cyclipostins And Related Compounds, Christopher Spilling

Chemistry & Biochemistry Faculty Works

Cyclophostin, the cyclipostins and the salinipostins are structurally related cyclic enolphosphate natural products. This mini review describes their isolation, synthesis and biological activities. In addition, the synthesis and biological activities of monocyclic enolphosphate and mono and bicyclic enolphosphonate analogs are presented.

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, 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 …

Acid-Mediated N-Iodosuccinimide-Based Thioglycoside Activation For The Automated Solution-Phase Synthesis Of Α-1,2-Linked-Rhamnopyranosides, Victoria R. Kohout, Alyssa L. Pirinelli, Nicola L.B. Pohl

Chemistry Publications

Carbohydrate structures are often complex. Unfortunately, synthesis of the range of sugar combinations precludes the use of a single coupling protocol or set of reagents. Adapting known, reliable bench-chemistry reactions to work via automation will help forward the goal of synthesizing a broad range of glycans. Herein, the preparation of di- and tri-saccharides of alpha 1→2 rhamnan fragments is demonstrated using thioglycoside donors with the development for a solution-phase-based automation platform of commonly used activation conditions using N-iodosuccinimide (NIS) with trimethylsilyl triflate. Byproducts of the glycosylation reaction are shown to be compatible with hydrazine-based deprotection conditions, lending broader functionality …

Unconventional Anticancer Metallodrugs And Strategies To Improve Their Pharmacological Profile, Maria Contel

Publications and Research

No abstract provided.

A Molecular Reconstruction Approach To Sitebased 3d-Rism And Comparison To Gist Hydration Thermodynamic Maps In An Enzyme Active Site, Crystal Nguyen, Takeshi Yamazaki, Andriy Kovalenko, David A. Case, Michael K. Gilson, Tom Kurtzman, Tyler Luchko

Publications and Research

Computed, high-resolution, spatial distributions of solvation energy and entropy can provide detailed information about the role of water in molecular recognition. While grid inhomogeneous solvation theory (GIST) provides rigorous, detailed thermodynamic information from explicit solvent molecular dynamics simulations, recent developments in the 3D reference interaction site model (3D-RISM) theory allow many of the same quantities to be calculated in a fraction of the time. However, 3D-RISM produces atomic-site, rather than molecular, density distributions, which are difficult to extract physical meaning from. To overcome this difficulty, we introduce a method to reconstruct molecular density distributions from atomic site density distributions. Furthermore, …

Synthesis Of New Aliphatic Pseudo-Branched Polyester Co-Polymers For Biomedical Applications, Zachary Shaw

Electronic Theses & Dissertations

In this study, a hyperbranched polyester co-polymer was designed using a proprietary monomer and diethylene glycol or triethylene glycol as monomers. The synthesis was carried out using standard melt polymerization technique and catalyzed by p-Tolulenesulfonic acid. The progress of the reaction was monitored with respect to time and negative pressure, with samples being subjected to standard characterization protocols. The resulting polymers were purified using the solvent precipitation method and characterized using various chromatographic and spectroscopic methods including GPC, MALDI-TOF, and NMR. We have observed polymers with a molecular weight of 29,643 kDa and 33,996 kDa, which is ideal to be …

Effects Of Ionic Liquid Alkyl Chain Length On Denaturation Of Myoglobin By Anionic, Cationic, And Zwitterionic Detergents, Joshua Y. Lee, Katherine M. Selfridge, Eric M. Kohn, Timothy Vaden, Gregory A. Caputo

College of Science & Mathematics Departmental Research

The unique electrochemical properties of ionic liquids (ILs) have motivated their use as solvents for organic synthesis and green energy applications. More recently, their potential in pharmaceutical chemistry has prompted investigation into their effects on biomolecules. There is evidence that some ILs can destabilize proteins via a detergent-like manner; however, the mechanism still remains unknown. Our hypothesis is that if ILs are denaturing proteins via a detergent-like mechanism, detergent-mediated protein unfolding should be enhanced in the presence of ILs. The properties of myoglobin was examined in the presence of a zwitterionic (N,N-dimethyl-N-dodecylglycine betaine (Empigen BB®, EBB)), cationic (tetradecyltrimethylammonium bromide (TTAB)), …

An Unexpected Rhenium(Iv)–Rhenium(Vii) Salt: [Co(Nh3)6]3[Reviio4][Reivf6]46h2o, James Louis_Jean, Samudee Mariappan Balasekaran, Adelheid Hagenbach, Frederic Poineau

Chemistry and Biochemistry Faculty Research

The title hydrated salt, tris[hexaamminecobalt(III)] tetraoxidorhenate(VII) tetrakis[hexafluoridorhenate(IV)] hexahydrate, arose unexpectedly due to possible contamination of the K2ReF6 starting material with KReO4. It consists of octahedral [Co(NH3)6] 3+ cation (Co1 site symmetry 1), tetrahedral [ReVIIO4] anions (Re site symmetry 1) and octahedral [ReIVF6] 2 anions (Re site symmetries 1and 3). The [ReF6] 2 octahedral anions (mean Re—F = 1.834 A˚ ), [Co(NH3)6] 3+ octahedral cations (mean Co—N = 1.962 A˚ ), and the [ReO4] tetrahedral anion (mean Re—O = 1.719 A˚ ) are slightly distorted. A network of N—HF hydrogen bonds consolidates the structure. The crystal studied was refined as a …

A New Approach To The Potential Energy Of Solids, Radhika Chauhan, Sanjeev K. Verma, Anushri Gupta, Anita Kumari, B. D. Indu

Karbala International Journal of Modern Science

A general theory is developed to investigate the expression for potential energy without using (i) empirical results and (ii) process of parameterizing. The simple approach of thermodynamics is adopted to obtain the expressions for the interaction energy of solids in terms of interatomic separation and crystal volume. The new findings have been applied to obtain the expressions for bulk modulus and pressure. The variation of the potential energy function, which provides a means to understand the stability of a crystal has been found in excellent agreements to the earlier results. The use of obtained harmonic and anharmonic force constants may …

Kinetic Study For The Effect Of New Inhibitors On The Activity Of Purified Gpt From Blood Of Cardiovascular Patients, Firas Maher

Karbala International Journal of Modern Science

In this study several biochemical parameters for cardiovascular patients have been measured CK-MB ,LDH ,GPT and GOT in addition to lipid profile , MDA ,Vitamin C and Vitamin E . New derivatives of ascorbic acid have been synthesized and tested to inhibit the purified GPT from the blood of cardiovascular patients Glutamate pyruvate transaminase (GPT) was purified from cardiovascular patients using ammonium sulphate salt for precipitation then dialysed using 0.1 M Tris-HCL buffer pH7.8 , then filtrated by gel filtration chromatography using Sephadex G-100 , followed by electrophoresis using poly acrylamide – bis acrylamide and sodium dodecyl sulphate (SDS). Derivatives …

Neighborhoods And Partial Sums Of A New Class Of Meromorphic Multivalent Functions Defined By Fractional Calculus, Aqeel Ketab Al-Khafaji, Waggas Galib Atshan, Salwa Salman Abed

Karbala International Journal of Modern Science

In this paper, we introduce and study a new class A^* (λ,μ,ν,η,p,ζ,τ) of meromorphic multivalent functions defined by fractional calculus operator of the punctured unit disc U^*. On this class we obtain several results like, coefficient inequality, modified Hadamard product, (N,δ)- neighborhood, partial sums, convex linear combination and integral operator.

Biomedical Applications Of Chasmanthera Dependens Stem Extract Mediated Silver Nanoparticles As Antimicrobial, Antioxidant, Anticoagulant, Thrombolytic, And Larvicidal Agents, Daniel Ayandiran Aina, Oluwafayoke Owolo, Agbaje Lateef, Folasade O. Aina, Abbas Saeed Hakeem, Morenike Adeoye-Isijola, Victor Okon, Tesleem B. Asafa, Joseph Adetunji Elegbede, Olumide D. Olukanni, Isaac Adediji

Karbala International Journal of Modern Science

The stem extract of Chasmanthera dependens was used in the biofabrication of silver nanoparticles (AgNPs) in this study. The AgNPs was characterised using UV-visible spectroscopy, Field Emission Scanning Electron Microscope (FESEM), EDX, and the Fourier Transform Infrared Spectroscopy (FTIR). Antibacterial, antioxidant, anticoagulant, thrombolytic and larvicidal activities of the biosynthesised nanoparticles were carried out. There was a peak at 418 nm with a strong silver peak observed around 2.7KeV when the EDX analysis was carried out. The FESEM showed a large number of cubically shaped nanoparticles with sizes ranging from 24.53 to 92.38 nm. CDE-AgNPs was effective against Klebsiella pneumoniae at …

Editorial Board

Karbala International Journal of Modern Science

No abstract provided.

The Ability Of A Tetrel Bond To Transition A Neutral Amino Acid Into A Zwitterion, Mingchang Hou, Qing-Zhong Li, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The interaction between glycine and F2CO/F2SiO occurs through the formation of a π-tetrel bond between the C/Si atom and a carboxyl O atom. The interaction energy is some 20 kJ/mol for the C···O tetrel bond, but exceeds 300 kJ/mol for Si···O. As part of the latter complexation process, the proton engaged in the intramolecular OH··N H-bond is transferred across to the N, forming a zwitterion. This Si···O tetrel bond is more effective at inducing this proton transfer than is placement of the glycine in an aqueous medium, complexation with an anionic BH4-, or adding an electron to the glycine.

Modified Ambient Mass Spectrometric Methods For Field Screening And Confirmation Of Forensic Evidence, William Lee Fatigante

Theses and Dissertations

The utility of field-portable analytical instrumentation has the potential to revolutionize many fields of science, particularly for forensic science and law enforcement. While colorimetric testing can be employed for drug evidence screening, the influx of novel psychoactive substances has significantly decreased the effectiveness of this investigation strategy. One approach to meeting the needs of today’s practitioner is coupling flexible, ambient ionization techniques with portable mass spectrometric (MS) instrumentation. Ambient ionization techniques have a rich history of being amendable to the sample at hand. Since their inception in 2005, numerous techniques saturate the field. The main drive for this development is …

An Insight Into The Biological Functions, The Molecular Mechanism And The Nature Of Interactions Of A Set Of Biologically Important Proteins., Adam A. Aboalroub

USF Tampa Graduate Theses and Dissertations

Characterization of protein structural properties is crucial to determine its role in normal and pathological conditions. In this dissertation, we have employed NMR spectroscopy in a combination of other biochemical and biophysical techniques to investigate the catalytic function, the molecular mechanism, and nature of the interactions of bmAANAT3, Cdc37, and TIMP2, respectively.

In the first project, we have employed an arylalkylamine N-acetyltransferases (AANATs) from Bombyx mori (bmAANAT3) to determine the role of the acetyl-group in coordinating the catalytic cycle in this family of enzymes. We have found that the occupancy of the acetyl-moiety in the catalytic funnel of these enzymes …

Design And Synthesis Of Novel Agents For The Treatment Of Tropical Diseases, Linda Corrinne Barbeto

USF Tampa Graduate Theses and Dissertations

Infectious diseases have had an impact on populations since the beginning of humanity. Despite huge advances in the fight against these conditions, they continue to be the leading cause of death and disability for a large portion of the world’s populace. Those most adversely affected predominately live in the more improvised areas of the developing world. Often treatments are made inaccessible to these areas due to cost, complicated administration requirements, severe side effects, and / or compound instability. Even when treatments are available the accelerated development of resistance has created an urgent need for the creation of new molecules with …

Selective Excited-State Dynamics In A Unique Set Of Rationally Designed Ni Porphyrins, Brian Pattengale, Qiuhua Liu, Wenhui Hu, Sizhuo Yang, Peilei He, Sir Lawrence Tender, Yingqi Wang, Xiaoyi Zhang, Zaichun Zhou, Jian Zhang, Jier Huang

Chemistry Faculty Research and Publications

In this work, we report the design and photophysical properties of a unique class of Ni porphyrins, in which the tert-butyl benzene substituents at the meso positions of the macrocycle were tethered by ethers with alkyl linkers. This not only results in the permanently locked ruf distortion of the macrocycle but also enables the engineering of the degree of distortion through varying the length of alkyl linkers, which addressed the complication of uncertainty in the specific structural distortions that has long plagued the porphyrin photophysical community. Using advanced time-resolved optical and X-ray absorption spectroscopy, we observed tunability in the …

Organic Chemistry With A Biographical Emphasis: Solutions To In-Chapter Exercises, Timothy Soderberg

Chemistry Publications

The solutions to the in-chapter exercises of Organic Chemistry with a Biological Emphasis volume 1 and 2.

Organic Chemistry With A Biological Emphasis: Solutions To Selected End-Of-Chapter Problems, Timothy Soderberg

Chemistry Publications

The solutions to the in-chapter exercises of Organic Chemistry with a Biological Emphasis volume 1 and 2.