Chemistry Commons^™

Metal-Organic And Supramolecular Architectures Based On Mechanically Interlocked Molecules, Isurika Rosini Fernando

Dissertations

The focus of this work is on mechanically interlocked molecules (MIMs), which have unusual physicochemical and mechanical properties with potential applications in nano-scale/molecular devices and high strength materials.

Rotaxanes, for example, consist of an axle-like molecule threaded through a wheel-like molecule, with bulky groups at the two ends of the axle preventing the wheel from dissociating. The position of the wheel along the axle can be switched in a controllable and reversible manner by applying external stimuli, a feature that might lead to the next generation of computers. Molecularly woven materials (MWMs), another example of molecules with mechanically interlocked features, …

Direct Analysis Of Hops By Leaf Spray And Paper Spray Mass Spectrometry, Kari Blain

Masters Theses

The objective of this research is to develop a new and innovative method of hops analysis, which is much faster than standard testing methods, as well as reduce the amount of consumables and solvent used. A detailed discussion on the development of an ambient ionization mass spectrometry method called paper spray (PS-MS) and leaf spray (LS-MS) mass spectrometry will be presented. This research investigates the use of PS-MS and LS-MS techniques to determine the α- and β- acids present in hops. PS-MS and LS-MS provide a fast way to analyze hops samples by delivering data as rapidly as a UV-Vis …

Equipment Qualification Of Ion Mobility Spectrometry And Method Development And Validation For Pharmaceutical Equipment Cleaning Validation, Amy Lee Heiser

Masters Theses

Ion mobility spectrometry (IMS) instrumentation has been identified as a suitable technology for the detection and reporting of drug product and detergent residues from pharmaceutical manufacturing equipment. Ion mobility is not a new technology, but is entering the field of cleaning validation because of tightened requirements from the US Food and Drug Administration (FDA).

The purpose of this thesis is to outline a practical implementation of the analytical technique, Ion Mobility Spectrometry in a cleaning validation program. Ion Mobility Spectrometry (IMS) is fast and specific for the analysis of small organic molecules and has been gaining popularity in the pharmaceutical …

Synthesis Of 1,1-Dialkyhydrazines And Their Hydroxyl Radical Degradation In Aqueous Environments, Benjamin F. Strong

Masters Theses

Determination of hydroxyl radical rate constants are essential to ensure adequate degradation of contaminants in wastewater. Hydrazines are an important class of organic contaminants and are the focus of this research. Ten 1,1-dialkylhydrazines are synthesized by the zinc reduction of the corresponding N-nitrosamines. Their hydroxyl radical rate constants are determined using the linear accelerator at the Notre Dame Radiation Laboratory at pH 4, 7, and 10.

Their rate constants are found to depend on the protonation state of the molecule. At pH 4 the molecules are fully protonated and hydrogen atom abstraction is favored from the alkyl chains. At …

Investigating The Biochemical Activity Of Some Flavonoids, Coumarins And Modified Gold-Nanoparticles As Anti-Breast-Cancer Agents, Amr Ezzat Mohamed Mahmoud

Dissertations

Polyphenols compounds are abundant natural products found in many plants as secondary metabolites. These compounds display many interesting pharmacological activities, which have motivated chemists over the years to explore them, and their synthetic derivatives, as potential drugs, especially anticancer drugs. Breast cancer is the most common cancer in women globally, and in the United States of America the estimated worldwide new breast cancer cases and the number of deaths are 1.38 million and 458 thousand, respectively. Currently in the USA there are 2.6 million women who have been treated for breast cancer, and the estimated number of deaths are 39,520 …

Investigation Of Saccharide Release Through Acidification, Sonication, Thermal, And Microwave Treatments, William K. Storck

Honors Theses

With diminishing fossil fuels, renewable sources are becoming much higher in demand. Algae are becoming an increasingly important source of biofuels. Production of biofuels from algae exceeds yields from every other source, most notably corn, per acre. It also provides a highly viable method of reusing carbon dioxide and does not compete with other crops for growth. The production of ethanol through fermentation requires the release of saccharides produced by the algae. The more saccharides extracted, the more ethanol can be produced. This project investigates for a more effective method of maximum saccharide release.

The purpose of this project is …

Interaction Of Pharmaceutical Compounds With Dissolved Organic Matter, Carlen Nigl Smith

Honors Theses

Highly prescribed pharmaceutical compounds and their metabolites used to treat conditions ranging from infections to depression are of environmental concern as these excreted compounds are increasingly appearing in wastewater influent. As pharmaceuticals enter treatment plants they also can interact with dissolved organic matter (DOM) present. This potential interaction between pharmaceutical compounds and DOM may inhibit the advanced oxidation process (AOP) based removal of drugs during water treatment. The focus of this research was to utilize multinuclear magnetic resonance and hydroxyl radical kinetics to assess whether an interaction between influent pharmaceuticals and DOM does occur, the extent of the interaction, and …

Multiphoton Fluorescence Spectroscopy To Monitor The Folding/Unfolding Of The N-Terminal Domains 5-6 Of Wilson Disease Protein, Ibtesam Y. Alja'afreh, Ramakrishna Guda, David Huffman

Research and Creative Activities Poster Day

Denaturation of the N-terminal domains 5-6 of Wilson Disease protein has been monitored through its mutant WLN5-6Cys51 by circular dichroism (CD), one and two-photon fluorescence spectroscopy after binding it to the thiolreactive dye 7-diethylamino-3-(4‘-maleimidylphenyl) -4-methylcoumarin (CPM). Far-UV CD measurements have shown that the mutations and the binding of the dye did not affect the secondary structure of the protein as the unfolding transition remained constant. The fluorescence maximum of the dye changed with the denaturant concentration and followed the trend obtained from CD and shown that one dye labeled protein can be used to monitor the unfolding of protein. Interestingly, …

Optical And Electrochemical Sensors For The Detection Of Metal Ions And Nerve Gas Mimics Via Fluorescein And Coumarin Derivatives, Fasil Adefris Abebe

Dissertations

Trace element detection of metals, for example, iron, Copper and zinc, are important in biological systems and in the environment. Many of us are aware that our cells contain metal ions that are “tied” up in proteins. However, chelatable or “free” trace elements can also be found in small quantities, and can have a negative impact on our bodies. Despite the increasing surge in developing sensors for metals and nerve gas agents, efficient detection still remains a challenge. Among the various sensors developed so far, fluorescence sensors play an important role due to their simplicity. I design fluorescein-based chemosensors for …

Optical And Electrochemical Properties Of Monolayer Protected Gold Clusters Modified With Fluorophores, Mary Sajini Devadas

Dissertations

My research focused on the synthesis, characterization and the investigation of the optical and electrochemical properties of monolayer-protected quantum-sized gold clusters. Significant research attention was focused on the solution phase optical and electrochemical properties of these clusters. Highly monodisperse Au clusters with different types of ligands were successfully synthesized with sizes varying from 1 nm to 13 nm. These preformed gold clusters were modified with fluorophores and pseudo-rotaxanes for developing better nonlinear optical materials for sensing and biological imaging purposes. We have tried to focus on the interaction of the outer ligand shell, made up of –S-Au-S-Au-S- bonds, with the …

The Impact Of Driving Conditions On Phev Battery Performance, Nathan Christensen, John Patten, Steven Srivastava, Gary P. Nola

Green Manufacturing Research Journal

The battery performance of a modified Prius with a 5 kWh plug-in battery was documented for a year to determine the impact of environmental conditions and user attributes on vehicle performance.  Both fuel economy and pure electrical efficiency were compared to ambient temperature.  The fuel economy has a positive relationship with ambient temperature until approximately 70˚F where the efficiency begins to drop.  Electrical performance has a positive linear relationship with ambient temperature.  With the emergence of electric vehicles (EVs) and PHEVs from a variety of automotive manufacturers, information on EV and PHEV performance for consumers will become more important.

Characterizing Potential Sustainable Energy Feedstocks, Jesse George Thompson

Dissertations

Trap grease offers a promising and less expensive alternative to food grade vegetable oils for biodiesel production, but its commercial marketability could be affected by its intense and offensive odor. Identification, quantitation and eventual elimination of the odorant compounds are vital challenges that need to be addressed before commercialization can be achieved. A rapid method using HS-SPME and GC/MS was developed in this study to identify and quantify the major volatile odorant compounds present in trap grease. The main odorant compounds were identified as short chain free fatty acids (SC-FFA) from C₄ - C₁₀.

Sensory evaluations by …

Glucosamine-Induced Insulin Resistance In Primary Rat Hepatocytes And The Role Of Selenium As An Insulin Mimetic, Sandhya N. Adiyodi Veetil

Dissertations

Type 2 diabetes is mediated by insulin resistance, the inability of insulin to elicit a normal biological response in insulin responsive tissues. Several cellular models have been utilized to determine the mechanism of induction of insulin resistance but questions remain unanswered. One model, implicates the products of the Hexosamine Biosynthetic Pathway (HBP) in the induction of insulin resistance under hyperglycemia. The major end product of HBP, UDP-GlcNAc, is the substrate for O-GlcNAc transferase, an enzyme that catalyzes the O-GlcNAcylation of numerous proteins. This modification may play a role in induction of insulin resistance and thus needs to be evaluated in …

Spectroscopic Study Of New Sensors For Organophosphates, Metals, And Cyanide Based On Rhodamine And Cholic Acid Derivatives, Arambe Gedara Aruna Weerasinghe

Dissertations

Despite the increasing interest in developing sensors for nerve gas agents, efficient detection remains challenging. Among the various sensors developed so far, fluorescence sensors play an important role due to their simplicity. We developed six new rhodamine-based compounds that can be used as fluorescent turn-on sensors. Compound 1 and 3 gave high fluorescent enhancement with diethyl chlorophosphate (DCP) compared to the other compounds. Very high selectivity and sensitivity were observed as these compounds did not show significant fluorescent enhancement with dimethyl methylphosphonate (DMMP), HC1 and transition metal ions. The potential sensor can be used in solution as well as on …

Biochemical Characterization Of Theromin, A Novel Leech Inhibitor, And The Interaction Between The Fourth Metalbinding Domain Of Wilson Disease Protein And Its Copper(I) Chaperone Hah1, Brian A. Zeider

Dissertations

Theromin, a novel thrombin inhibitor from the leech Theromyzon tessulatum, has been shown to be the strongest inhibitor to date. There has been a lot of attention on direct thrombin inhibitors as a much more efficient drug for anticoagulation therapy. One main reason for the need of strong direct thrombin inhibitors is that the current therapy, heparin, causes alternative clotting events in some patients where antibodies are made to the heparin/thrombin complex and causes clots to occur by different methods. Recently there has been a strong inhibitor from a leech used, hirudin, that can inhibit with a K_{i …}

Synthesis And Characterization Of Monolayer Protected Gold Nanoparticles And A Gold-Titanium Dioxide Nanocomposite Intended For Photocatalytic Degradation Of Environmental Pollutants, Piyadarsha Amaratunga

Dissertations

Semiconductor and metal clusters in the nanometer size regime display interesting optical, electronic and chemical properties that are size dependant. Highly monodisperse gold nanoparticles of different sizes have been synthesized and isolated by newly developed methodologies, using tiopronin as the capping ligand. Titanium dioxide nanoparticles (Ti0₂) have been used as the photocatalytic center and gold nanoparticles have been attached on Ti0₂ to make a nanocomposite. According to the findings, gold nanoparticles play a vital role in enhancing the photocatalytic activity of Ti0₂, by facilitating the charge separation. Further, the photocatalytic activity also can be tuned …

Isotropic And Anisotropic Metallic And Bimetallic Nanoparticles And Their Potential Applications In Biology, Minghong Liu

Dissertations

The development of synthetic procedures that produce nanoscale materials with controlled morphology is a significant area of investigation in nanotechnology. We have developed new synthetic procedures for fabrication of isotropic and/or anisotropic nanomaterials composed of palladium, ruthenium, nickel and alloys of palladium-ruthenium. The nanomaterials were fully characterized and were found to display unique size dependent properties. The electrochemical properties of isotropic palladium, ruthenium and palladium-ruthenium nanoparticles were investigated and the results showed that the particles were capable of charge storage and charge transfer on demand. Anisotropic palladium, ruthenium and palladium ruthenium nanoparticles were also fabricated and fully characterized. The nanoparticles …

Gold Nanoparticle - Modified Zinc Oxide Nanoparticles As Novel Photocatalytic Materials, Nayane Udawatte

Dissertations

The current study entails the construction of a novel nano-composite catalyst based on ZnO and Au nanoparticles and demonstrates its distinctive photocatalytic characteristics. Monodisperse gold nanoparticles (GNPs) passivated with monolayers of tiopronin or glutathione were synthesized via facile methods, and they were assembled on ZnO nanoparticles to form the nanocatalyst.

Steady state and time resolved photoluminescent studies on the nanocomposite revealed interesting charge transfer characteristics within the nanocomposite. Enhanced photooxidation of rhodamine 6G was observed for the nano-composite over bare ZnO, and modulation of photoactivity with the extent of GNP loading was illustrated. Photoreduction of thionine over the nanocomposite was …

The Lipid Acyl-Chain Dynamics In Giant Liposomes And Characterization Of Domain 4 Of The Wilson Disease Protein, Wilson Okumu

Dissertations

Steady-state and nanosecond time-resolved fluorescence of the nitro-2, 1, 3- benzoxadiazol-4-yl (NBD) probe and line tension force were determined in phospholipids acyl-chain dynamics in giant liposomes made from a homologous series of phosphatidylcholines (PC). The fluorescence spectroscopy of a NBD probe attached to the headgroup (NBD PE) or the tail (NBD PC) of the phospholipid were used to determine the rate of dithionite quenching in a homologous series of phospholipids. Similar experiments were performed in the gel and the fluid phases of the l,2-dimyristoyl-s«-glycero-3-phosphocholine (DMPC ). Nanosecond time scale lifetimes and anisotropy measurements were obtained by a 470 nm LED …

Characterization Of The N-Terminal Domains And Disease-Causing Mutations Of The Human Wilson Protein, Joshua Mutambuki Muia

Dissertations

The Wilson protein (ATP7B) is a copper transporting ATPase that is involved in copper trafficking and homeostasis. Unlike the other known P-type ATPases, it possesses six homologous metal binding domains at the N-terminal end. Several mutations in the gene coding for this protein lead to Wilson disease, a hepatic disorder characterized by impaired excretion of copper in the bile, and accumulation of copper in body organs such as the liver, brain, kidney, and eye cornea. Characterization of various regions of expressed and purified ATP7B has been hampered by its low stability, aggregation and degradation.

In this research, novel methods were …

Designing Molecular And Nanoscale Materials For Environmental Chemistry Processes, Wen Guo

Dissertations

This dissertation focuses on fundamental studies to identify materials that detect and degrade common organic environmental pollutants. Chapter 1 represents the overview of two widespread ground water contaminants: organohalides and organophosphorous compounds. Due to continuous usage of these compounds as well as their toxicity, reliable and sensitive methods for their detection and degradation are urgently needed. In Chapter 2 a description of molecular sensors designed with high sensitivity and selectivity to detect and distinguish between three organophosphorus (OP) pesticides are described. These sensors provide dual optical and electrochemical signals for detection, which minimizes false-positives. The signal transduction occurs in real …

The In-Situ Removal Of Menthofuran From Peppermint Oil And Subsequent Reactions Of The Solid-Supported Adduct, Robert Joseph Justice Ii

Dissertations

Menthofuran is an aromatic heterocyclic compound found naturally in the essential oil of Mentha piperita L. or peppermint. Natural peppermint oil may contain between approximately 2 to 8% menthofuran.

Peppermint oil is a complex mixture of over 350 identified chemical compounds; market demands dictate the extent of processing the oil undergoes prior to being introduced into consumer goods. Menthofuran has long been known to readily autoxidize, either alone or within the peppermint oil matrix, leading to a discolored oil with negative organoleptic consequences that adversely affects its commercial viability. Therefore, a facile method for selective removal of menthofuran was developed …

Evaluation Of Electron Donor Materials Used To Create Subsurface Permeable Reactive Barriers For Enhanced Reductive Dechlorination Of Chlorinated Ethenes, Elizabeth S. Semkiw

Dissertations

Chlorinated ethenes (CEs) are widespread ground water contaminants, apparently due to their extensive migration from numerous contamination source points. In this study, a long-term field investigation and aquifer microcosm experiments were combined to evaluate the effectiveness of electron donor materials used to create and maintain subsurface permeable reactive barriers (PRBs) for the enhanced in-situ biodegradation of CEs. The laboratory component includes the first side-by-side comparison of electron donor materials dairy whey, lactate syrup, and Hydrogen Release Compound® (HRC), in which dechlorination rates, fermentation product distributions, and H₂ production were monitored as measures of substrate efficiency. Field study allowed the …

Switch On And Switch Off Nanosensors For The Detection Of Nerve Gas Agents, Shankar Varaganti

Dissertations

The central hypothesis of this research is the development of novel nanosensors by a bottom-up approach for the detection of nerve gas agents. The nanosensor assembly consists of four main parts; nanoparticles (N), Monomer (M), Complex (C) and Receptor (R). Two novel Ru (II)-bipyridyl and zinc complexes with tryptophan receptors either in 4,4' or 5,5' position of the bipyridyl ring have been synthesized and characterized by using ¹H NMR, ¹³C NMR, mass spectrometry and absorption spectroscopy. Silica nanoparticles or quantum dots are used as a platform for the nanosensors. Highly conjugated stilbene type compounds are used as monomers. …

Origin Of Size-Dependent Energy Transfer From Photoexcited Cdse Quantum Dots And Fluorescent Dyes To Gold Nanoparticles, Mariana Kondon

Masters Theses

The photoluminescence quenching of CdSe quantum dots (QD) and fluorescent dyes by hexanethiolate Mono layer Protected Clusters (MPCs) with core diameters of 1.1- 4 .9 nm is described.

The CdSe QD investigated had the following core diameters of 2.0, 2.6, 3.4 and 6.9 nm. The florescent dyes used were: Coumarin 440 (CM440), Fluorescein 548 (F548), Rhodamine 6G (R6G), Pyromethene 597 (PM597) and Lyssamine Dye (LD700). Experimental evidence suggests that the photoluminescence quenching of both CdSe QD and the fluorescent dyes occurs through energy transfer and that the AuMPCs are efficient quenchers in both cases. The larger MPCs are more efficient …

Optical And Electrochemical Molecular And Nanoscale Sensors For The Selective Detection Of Organophosphorus Based Pesticides, Chandrima De

Masters Theses

Organophosphorus based pesticides are highly toxic and represent serious environmental concerns. These compounds tend to easily enter ground water and cause drastic pollution. The toxicity levels of the organophosphorus pesticides however are based on their structures, and hence methods for their selective detection are in high demand. The creation of new materials for sensing and actuation requires careful manipulation of the responsive units required to control analyte selectivity. We have successfully designed and synthesized a molecular sensor based on the family of stilbenes that not only can detect organophosphorus pesticides, but also distinguish between them. Four different pesticides have been …

Characterization Of P62, Hah1 And Their Interaction With The Wilson Disease Protein, Paul Sifuna Oshule

Masters Theses

Wilson disease is an autosomal recessive disorder resulting in the accumulation of copper in the body primarily in the liver and brain. In order to understand the pathogenesis of Wilson disease, our laboratory is studying several different proteins. Wilson disease protein (ATP7B) is a P-type ATPase which acts to remove excess copper from the cells. The p62 subunit of the dynactin complex is a protein whose function is still unknown but it has been proposed to have a copperdependent interaction with ATP7B. HAH1 is a human metallochaperone that binds copper as it comes into the cells from CTR1, a permease. …

Blocked Localized Wavefunction Analysis Of Π And Σ Bonds In The Metal Carbonyl, Kazuhito Nakashima

Masters Theses

The bonding features in group 10 and 11 metal carbonyls Ni(CO), Pd(CO), Pt(CO), [Cu(CO)]+, [Ag(CO)]+, and [Au(CO)]+ have been studied with BLW method. The carbon monoxide is well known as both a π acceptor and a σ donor. The π back bonding and o bonding are synergistic in these metal carbonyl complexes, because the π donation from the metals polarizes the metals and creates a negative force field as an additional driving force on the σ donation from the carbon end of CO vice versa. The synergistic effect in the metal-carbonyl bonds can be described by decomposing the binding energy …

Synthesis, Characterization, And Catalytic Application Of Gold Nanoparticles, Junhyung Kim

Dissertations

Properties of nanometer-sized gold(Au) particles, especially those that are protected by a monolayer coating of thiolate ligands, called 'Monolayer Protected Clusters' (MPCs), are of rigorous multidisciplinary interest for their potential applications in catalysis and electronics due to their variation with size.

In larger core diameter sizes (>1.5nm) AuMPCs show metallic behavior as observed from electrochemical measurements. On the other hand, sub-nanometer ([approximate]1.1nm) AuMPCs exhibit molecule-like electronic behavior which is typical of Au38 nanoparticles. The various alkane chain thiols(C4 S-C12 S) capped Au38 MPCs have been examined with independent analytical tools, producing a remarkably consistent picture of these materials.

The …

Exploration Of The Chemical And Biological Processes Through Molecular Dynamics Simulation And Blocklocalized Wavefunction Method, Yuchun Lin

Dissertations

Computer simulation plays a crucial role in interpreting, unifying and guiding experimental observations. In this dissertation, molecular dynamics (MD) simulations and the block-localized wavefunction (BLW) method have been used to explore the chemical and biological processes.

Detailed MD simulations were performed to study the transportation of NH₄⁺, NH₃ and H₂O through the Escherichia coli ammonium transporter (AmtB) membrane protein. A periplasmic recruitment vestibule was identified and the entrance of an NH₄⁺ into this vestibule requires only 3.1 kcal/mol. In the end of this vestibule, the phenyl ring of Phe107 dynamically opens and …