Chemistry Commons^™

Bio-Compatible Polymer Coatings Using Low Temperature, Atmospheric Pressure Plasma, Susan Farhat, Mary Gilliam, Ali Zand, Montserrat Rabago-Smith

Chemistry & Biochemistry Presentations And Conference Materials

Current research has been dedicated to investigating the viability of atmospheric pressure plasmas for use in coating technology. In addition to being more cost effective and efficient, atmospheric pressure plasma offers a more streamlined process, as it can be employed directly into the production line. Atmospheric pressure plasma has been used in applications including biocompatibility, hydrophilicity/hydrophobicity, and coating with antibacterial films. Polyethylene is used as a biocompatible surface for ball and socket joint replacements, which are under constant wear. Atmospheric pressure plasma treatment was used to change the surface chemistry by grafting various biocompatible polymers to the polyethylene surface, as …

Molecular Encapsulation In Kinetically Trapped, Hydrogen-Bonded Pyrogallolarene Hexamers, Jennifer Christine Chapin Lake

Electronic Theses and Dissertations

Pyrogallolarene and resorcinarene hexamers are hydrogen-bonded capsules that self-assemble in the solid state and can be studied in gaseous and solution phases. Guest loading within pyrogallolarene hexamers in solution has primarily been comprised of solvent molecules with some tertiary amines. A novel solvent-free method for loading guests into the interior of the hexamer has been shown to be effective for encapsulation of a variety of molecules. Aromatic and aliphatic compounds have particularly high guest loading within the hexamers and often result in kinetically stable guest-filled capsules in solution.

Kinetic studies of the encapsulation complexes of anthracene, biphenyl, fluoranthene, fluorene, naphthalene, …

Nitroxide Radicals For Low Frequency Electron Paramagnetic Resonance Imaging (Epri), Joshua R. Biller

Electronic Theses and Dissertations

Optimization of nitroxides as probes for EPR imaging requires detailed understanding of spectral properties such as spin lattice relaxation times, spin packet linewidths, and nuclear hyperfine splitting. Initial measurements of relaxation times for six low molecular weight nitroxides at X-band stimulated further measurement at frequencies between 250 MHz and 34 GHz. The impact of tumbling was studied with perdeuterated 2,2,6,6-tetramethyl-4-piperidinyl-1-oxyl (PDT) in five solvents with viscosities resulting in tumbling correlation times, τ_R, between 4 and 50 ps. A set of three ¹⁴N/¹⁵N pairs of nitroxides in water was selected such that τ_R varied between …

Fabrication Of Multifunctional Ferromagnetic Au₃Pd-Cose Nanoparticles, Wipula P. Liyanage, Sukhada Mishra, Kai Song, Manashi Nath

Chemistry Faculty Research & Creative Works

We have synthesized multifunctional anisotropic Au₃Pd-CoSe nanoparticles on Si substrate through a catalyst aided chemical vapour deposition technique. the technique utilized volatile cobalt acetylacetonate and elemental selenium as precursors while sputter coated Au-Pd (3:2) film acted as a catalyst. the typical growth conditions led to clear segregation of the hetero-compositions (i.e. Au₃Pd and CoSe) in the product nanostructures thereby preserving the functionality of both the phases. the degree of crystallinity of the individual phases in the composite nanostructure was fairly high. the bifunctional nanoparticles show soft ferromagnetic behaviour at room temperature and optical activity making them …

Development And Implementation Of Dispersion Phase Diagrams (Dpds) For Four Different Hydrophobically Modified Ethoxylated Urethane (Heur) Based Acrylic Paint Systems, Tyler J. Bell

Master's Theses

Latex polymers serve as binders in a wide range of architectural paints and coatings. A latex is an aqueous colloidal dispersion of polymer particles that when dried above the polymer’s film formation temperature coalesces into a dry polymer film (Dragnevski, Routh, Murray, & Donald, 2010). The other main components of paint include associative thickeners, surfactants, pigments and fillers with the thickener being the primary area of focus for this study.

The relatively simple system of latex, associative thickener and surfactant has been studied extensively. These studies have shown the mechanism of thickening for the associative thickener, and surfactant effects on …

An Investigation Of Poly(N-Isopropylacrylamide) For Applications With Microfluidic Paper-Based Analytical Devices, Haydn Thomas Mitchell

Master's Theses

N,N′-methylenebisacrylamide-crosslinked poly(N-isopropylacrylamide), also known as P(NIPAM), was developed as a fluid delivery system for use with microfluidic paper-based analytical devices (microPADs). MicroPADs are postage-stamp-sized devices made out of paper that can be used as platforms for low-cost, simple-to-use point-of-care diagnostic assays. P(NIPAM) is a thermally responsive polymer that absorbs aqueous solutions at room temperature and will expel the solutions to microPADs when heated. The fluid delivery characteristics of P(NIPAM) were assessed, and P(NIPAM) was able to deliver multiple solutions to microPADs in specific sequences or simultaneously in a laminar-flow configuration. P(NIPAM) was then shown to be suitable …

Octyl (2e)-2-[2-(Di­Phenyl­Phosphan­Yl)Benzyl­Idene]Hydrazinecarbodi­Thio­Ate, Izuddin Asri, Malai Haniti S. A. Hamid, Aminul Huq Mirza, Mohammad Akbar Ali, Mohammad Rezaul Karim

Chemistry Faculty Research

The title compound, C28H33N2S2P, adopts the thione tautomeric form, as supported by the C—S distance [1.6744 (18) Å]. The Schiff base exhibits an E conformation about the C=N bond but a Z conformation about the C—N bond. The terminal chain is disordered over two sets of sites with an occupancy ratio of 0.732 (3):0.268 (3). In the crystal, pairs of N—N—H hydrogen bonds between the thione groups link neighbouring mol­ecules into centrosymmetric dimers.

Chemistry Graduate Teaching Assistants: A Comparison Of The Classroom Discourse Within Expository And Problem-Based Learning Laboratories, Kelley M. Current

Masters Theses

Graduate Teaching Assistants (GTAs) commonly function as instructors within undergraduate chemistry laboratories. This study sought to explore and describe GTA classroom discourse within two distinct instructional modes, using discourse analysis as the theoretical framework. Theclassroom discourse within a series of verification style labs was comparedto the classroom discourse produced within a set of Problem-Based Learning (PBL) labs. The results suggest three primary findings: (1) the apparent relationship between the instructional mode and form of GTA classroom discourse, (2) the patterns in classroom discourse observed within a given instructional mode repeat, irrespective of content, and (3) the classroom discourse observed within …

Development And Validation Of Lc–Ms/Ms Method For Quantitative Determination Of (−)-Securinine In Mouse Plasma, Simuli L. Wabuyele, David Wald, Yan Xu

Chemistry Faculty Publications

(−)-Securinine (SE) is a major alkaloid found in plant Securinega suffruticosa, which has a wide range of pharmacological activities including anticancer, anti-parasitic and central nervous system stimulating effects, etc. To aid the pharmacological study of SE, we developed an LC–MS/MS method for quantitative determination of SE in mouse plasma. In this method, plasma samples were first prepared with salting-out assisted liquid–liquid extraction using cold acetonitrile (−20 °C) and 2.00 M ammonium acetate. Separation of SE and the internal standard (IS) from sample matrix was achieved on a Gemini Nx C18 column using 40% acetonitrile and 60% 10.0 mM ammonium acetate …

Improving Hybrid Solar Cells: Overcoming Charge Extraction Issues In Bulk Mixtures Of Polythiophenes And Zinc Oxide Nanostructures, Grant T. Olson

Master's Theses

Organic photovoltaics (OPVs) have received a great deal of focus in recent years as a possible alternative to expensive silicon based solar technology. Current challenges for organic photovoltaics are centered around improving their lifetimes and increasing their power conversion efficiencies. One approach to improving the lifetime of such devices has been the inclusion of inorganic metal oxide layers, but interaction between the metal oxides and common conjugated polymers is not favorable. Here we present two methods by which the interactions between polythiophenes and nanostructured ZnO can be made to be more favorable. Using the first method, direct side on attachment …

Discovery Of Novel Serum Biomarkers For Diagnosing And Staging Alzheimer's Disease, Dipti Jigar Shah

Theses and Dissertations

Discovery of Novel Serum Biomarkers for Diagnosing and Staging Alzheimer’s DiseaseDipti Jigar ShahDepartment of Chemistry and Biochemistry, BYUDoctor of PhilosophyAlzheimer’s disease (AD) is an untreatable neurologic disease affecting more than 5 million Americans, most over 60 years of age. Protein plaques and neurofibrillary tangles typify AD brain pathology and are thought to cause the progressive dementia and brain shrinkage observed in AD. Currently there are no methods to diagnose the disease at a time before damage becomes irreversible.Biochemical tests for AD using cerebrospinal fluid analysis or neuroimaging are not yet sufficiently sensitive and specific, and they are invasive. This points …

Biophysical Characterization Of The First Four Metal-Binding Domains Of Human Wilson Disease Protein, Alia V.H. Hinz

Dissertations

Wilson disease protein (WLNP) is a P_1b-type ATPase crucial for maintaining copper homeostasis in humans. Mutations in this protein result in the autosomal recessive disorder Wilson disease, a condition characterized by copper accumulation in the liver and brain. WLNP provides copper for incorporation into cuproproteins and exports excess copper into the bile for excretion. There are six metal-binding domains (MBDs) in WLNP, found within the first 650 amino acids of this 1,465 amino acid protein. Though each MBD has a different amino acid sequence, all MBDs possess a similar ferredoxin fold with a conserved hydrophobic core and a …

Heavy Metal Analysis In Lens And Aqueous Humor Of Cataract Patients By Total Reflection X-Ray Fluorescence Spectrometry, Martina Schmeling, Bruce I. Gaines, Susanne Tidow-Kebritchi

Chemistry: Faculty Publications and Other Works

The human eye is continuously exposed to the environment yet little is known about how much of toxins, specifically heavy metals are present in its different parts and how they influence vision and acuity. To shed light into this subject, aqueous humor and lens samples were collected from 14 cataract patients to study the presence and concentration of selected metals in the eye. Subjects undergoing routine cataract surgery were consecutively enrolled for study by simple random sampling. Prior to surgery, subject demographic were compiled. The surgical procedure involved small incision cataract removal using phacoemulsification. During the procedure, a small aliquot …

In Vitro Biosynthesis And Chemical Identification Of Udp-N-Acetyl-D-Quinovosamine (Udp-D-Quinac), Tiezheng Li, Laurie Simonds, Evgenii L. Kovrigin, K. Dale Noel

Chemistry Faculty Research and Publications

N-acetyl-d-quinovosamine (2-acetamido-2,6-dideoxy-d-glucose, QuiNAc) occurs in the polysaccharide structures of many Gram-negative bacteria. In the biosynthesis of QuiNAc-containing polysaccharides, UDP-QuiNAc is the hypothetical donor of the QuiNAc residue. Biosynthesis of UDP-QuiNAc has been proposed to occur by 4,6-dehydration of UDP-N-acetyl-d-glucosamine (UDP-GlcNAc) to UDP-2-acetamido-2,6-dideoxy-d-xylo-4-hexulose followed by reduction of this 4-keto intermediate to UDP-QuiNAc. Several specific dehydratases are known to catalyze the first proposed step. A specific reductase for the last step has not been demonstrated in vitro, but previous mutant analysis suggested that Rhizobium etli gene wreQ might encode this reductase. Therefore, this gene was cloned and expressed …

Nanocarbon Immobilized Membrane For Separation And Analysis, Madhuleena Bhadra

Dissertations

Membrane processes classically cover a wide range of applications associated with various aspects of separation and purification. Over the last few years, membrane based processes have received much interest due to their compact and modular architecture, low energy consumption and cost effective separation. With the development of diverse nanomaterials which can serve as nanosorbents, or provide specific morphology for selective solute transport, recent years have witnessed the emergence of nanocarbon based membranes that can address some of the limitations of conventional membrane processes and make feasible the next generation of breakthroughs.

The objective of this research is the exploration of …

Kinetics Of Solid Phase Crystallization Of A-Ge Thin Films, John D. Graham

Macalester Journal of Physics and Astronomy

A method was developed to investigate the solid-phase crystallization (SPC) reaction undergone by germanium thin films. Amorphous films were grown by the radio-frequency (RF) magnetron sputtering and then annealed for a maximum of 6 hours at two temperatures: 446°C and 460°C. Crystallinity was measured by resistivity measurements, as well as crystal peak height and area taken from X-ray diffractometer (XRD) data. Initial data shows qualitative agreement with a nucleation-growth model for the observed kinetic process. However, observed peak narrowing phenomena suggests a comprehensive model of XRD measurements of polycrystalline thin films is needed for a rigorous interpretation of the results.

Force Constants Of Coordinated Co And Β-Amino Substituted Isocyanides Using Infrared Spectroscopy, Laura Avena

Macalester Journal of Physics and Astronomy

Metal carbonyls and isocyanides have characteristic peaks in infrared spectra. While the energies are useful in a qualitative determination of relative bond strengths, a more quantitative approach is needed to cross-compare similar complexes. Using a harmonic oscillator approximation, it is possible to determine the effective force constants of carbon-oxygen and carbon-nitrogen bonds. This allowed me to show that negatively charged bis(diphenylphosphinomethyl)diphenylborate used in our laboratory is a better donor than its neutral analogue 1,2-bis(diphenylphosphino)ethane.

Use Of Carbon Dioxide (Co2) And Its Congeners For The Synthesis Of Small Value Added Chemicals Utilizing Chlorostannoxane Catalysts, Sharon Pulla

Theses and Dissertations

Carbon dioxide (CO2) is an abundant, environmentally benign and renewable source of carbon. Use of CO2 may potentially end the use of other toxic C1 synthons, such as phosgene, carbon monoxide, and isocyanate. However, the extreme inertness of CO2 presents great difficulty for its use in organic synthesis. In Chapter 3, the synthesis of cyclic carbonates from corresponding epoxides under low pressures of CO2 (300 psi), relatively mild temperature (130 oC) using chlorostannoxane catalysts is discussed. Activities of the catalysts have been optimized in the pressure range of 100-700 psi, temperature range of 100-130 oC, with reference to propylene oxide. …

Ab-Initio Study Of H2 Adsorption Upon The 001, 110, And 100 Surface Of Magnesium, Thomas F. Armstrong

Theses and Dissertations

Until recently, the only pathway for H2 adsorption onto conventional magnesium thin films was the [001] surface. With the discovery of Mg nanoblade/nanotree fabrication, there are now multiple surfaces for adsorption. A keen understanding of each surface's hydrogen adsorption kinetics is a key part of deciding if these surfaces present a more attractive hydrogen storage material than conventional thin films. This study focused on the use of ab-initio methods to compare the adsorption of H2 molecules onto the [001], [100], and [110] surfaces as well as an analysis of hybrid functionals and their advantages over traditional functionals for minimum energy …

Organic-Inorganic Hybrid Nanostructures For Solar Cell Applications, Samir Mahdi Abdulalmohsin

Theses and Dissertations

The enticing electro-optical properties of nanostructured materials such as carbon nanotubes, graphene, CdS nanocrystals and ZnO nanowrie bring new vigor into the innovation of photovoltaics. The main purpose of this dissertation is to develop novel nano-structured materials for low cost solar cell applications. Fabrication, characterization, and solar cell application of organic-inorganic hybrid structures are the main focus of this research. Polyaniline (PANI)/multi-walled carbon nanotube (MWNT) composite films were synthesized by an electrochemical polymerization of aniline with airbrushed MWNTs on ITO substrates. It was found that the incorporation of MWNTs in PANI effectively increase the film conductivity with a percolation threshold …

Microwave Assisted Synthesis And Characterization Of Selected Heteroatom Doped Carbons From Tannin For Alkaline Fuel Cell Applications & Ammonia Gas Sensors From Tanninsulfonic Acid Doped Polyaniline - Tio2/Al2o3 Composites, Venu Gopal Bairi

Theses and Dissertations

An alternative for depleting fossil fuel resources would be the development of fuel cells, batteries and solar cells. The current project aims at development of the cathode electrode material for alkaline fuel cells which is utilized for the reduction of oxygen to water. A simple, highly efficient, and rapid microwave method for the synthesis of doped carbons from different precursor sources like tannin, aminated tannin and tannin-melamine-hexamine has been developed. Different dopants include phosphorus, nitrogen, oxygen, sulfur and silicon. The method uses no inert or reducing gas during the transformation. Yields resulting from this particular technique are as high as …

Metal-Organic Frameworks Based On Pyridyl-Tetrazole Ligands Containing Ester Or Carboxylate Pendant Arms, Ursula Sheridan, John Gallagher, Morten Bjerrum, Adrienne Fleming, Fintan Kelleher, John Mcginley

Articles

The coordination of pyridyl-tetrazole derivatives containing ester substituents, at either the N-1 or N-2 position of the tetrazole ring, with copper(II) chloride results in the formation of either 1:1 or 1:2 copper to ligand complexes, depending on the ligand. However, when the ester functionality is changed to a carboxylate group, the resulting complexation reactions yield metal-organic frameworks. The resulting structures vary dramatically in pore size, depending on both reaction solvents and position of carboxylate group on the tetrazole ring. Despite the presence of sodium cations in the reaction mixtures, no sodium incorporation was ever observed in any of the complexes. …

High Ionic Strength Narrows The Population Of Sites Participating In Protein Ion-Exchange Adsorption: A Single-Molecule Study, Lydia Kisley

Faculty Scholarship

The retention and elution of proteins in ion-exchange chromatography is routinely controlled by adjusting the mobile phase salt concentration. It has repeatedly been observed, as judged from adsorption isotherms, that the apparent heterogeneity of adsorption is lower at more-eluting, higher ionic strength. Here, we present an investigation into the mechanism of this phenomenon using a single-molecule, super-resolution imaging technique called motion-blur Points Accumulation for Imaging in Nanoscale Topography (mbPAINT). We observed that the number of functional adsorption sites was smaller at high ionic strength and that these sites had reduced desorption kinetic heterogeneity, and thus narrower predicted elution profiles, for …

Roesner To Receive National Teaching Award, Kim Hill

News and Events (Discontinued Series)

No abstract provided.

Poly (N-Isopropylacrylamide) Microgel-Based Optical Devices For Sensing And Biosensing, Molla R. Islam, Andrews Ahiabu, Xue Li, Michael J. Serpe

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Responsive polymer-based materials have found numerous applications due to their ease of synthesis and the variety of stimuli that they can be made responsive to. In this review, we highlight the group’s efforts utilizing thermoresponsive poly (N-isopropylacrylamide) (pNIPAm) microgel-based optical devices for various sensing and biosensing applications.

Branching Into Rnai: Synthesis, Characterization And Biology Of Branch And Hyperbranch Sirnas, Anthony Muriithi Maina

Seton Hall University Dissertations and Theses (ETDs)

The cancer epidemic continues to afflict millions of humans world-wide each year and despite a renewed hope with the development of new and improved forms of therapy, a cure for cancer remains an elusive goal. This is partly related to the rise of resilient forms of tumors that have evolved with resistance towards conventional chemotherapy and radiation treatments. Moreover, these non-specific therapeutic regimens are highly toxic, leading to severe immunosuppressive effects which poisons the body and compromises the road towards remission. In an effort to mitigate these limitations, cancer-targeting approaches are currently experiencing a renaissance in the translation of new …

Ionic Liquids In Micro Extractions And Gas Chromatographic Stationary Phases, Ramkumar Dhandapani

Seton Hall University Dissertations and Theses (ETDs)

Ionic liquids are salts that exist entirely as ionic species. They are composed of cation, anion and side chain or linkage group. Due to the different combination of the these groups, the ionic liquid exhibits unique selectivity. Their applications are enormous in the field of analytical chemistry.

The interest of using ionic liquids as gas chromatographic stationary phase has increased in recent years. The low volatility, tailorable physico-chemical property and high thermal stability of ionic liquids make them an ideal choice for gas chromatographic stationary phase. For the present research, commercially available ionic liquid capillary columns were investigate for thermodynamics …

Laser Intensity And Ionic Strength Dependence Of The Aqueous Nitrate And Carbonate Ion Raman Spectra, Samuel White

Mahurin Honors College Capstone Experience/Thesis Projects

The geometry (and hence vibrational modes) of aqueous nitrate ion, NO₃^-, is known to depend on the solution composition—concentration, counter ions, etc. If a definite relationship between the vibrational spectrum and ionic strength of the solution could be established, it could be a useful monitor of solution composition over time. This would be valuable in studying the reaction rates and mechanisms of reactions involving nitrate in an aqueous environment, such as its photolysis in snow. Previous work in our lab observed a split peak at the symmetric-stretch mode of nitrate, though this mode does not usually show …

Mechanochemistry: Pyrene Derivatives In The Detection Of Select Metals, Hillary Asberry

Mahurin Honors College Capstone Experience/Thesis Projects

Metals are found naturally in the environment and expelled through industrial waste. When absorbed through the skin, inhaled, or ingested, many metals have been proven to cause numerous health problems. Mechanochemistry using a mortar and pestle grinding shows promise in capture and detection of toxic metals. This method allows for an on-site, cost effective, simple, solvent free, and environmentally friendly metal coordination. Pyrene derivatives with diethylenetriamine and bis(3-aminopropyl)amine linkers have shown to be successful fluorescent receptors serving as a Lewis bases in the reactions. After coordination, color changes are observed in visible light and UV light. Metal salts that exhibit …

Mercury Bioaccumulation In Bat Populations In Mammoth Cave National Park: Modern, Historical, And Ancient Samples, Stephanie Hagan

Mahurin Honors College Capstone Experience/Thesis Projects

The first human to enter Mammoth Cave passed under its arch about 4,000 years ago, but bats have been calling it home long before humans discovered it. Due to environmental exposure of mercury, these bats potentially show substantial mercury bioaccumulation. Bats now come into contact with mercury through atmospheric deposition from industrial sources. It is expected that the modern bats residing in Mammoth Cave should have measurable levels of mercury in their system which has been determined by guano analysis. Over fifty current samples of bat guano have been analyzed and exhibit mercury levels at the part per billion level. …