Chemistry Commons^™

Rational Ligand Design For Potential Applications In Transition Metal Catalysis, Sergey L. Sedinkin

Dissertations

Strategies to influence the steric and electronic properties of three classes of ligands were investigated. First, a compound class known as amino-dithiaphospholanes was studied. It is structurally related to phosphoramidites, which have been successfully applied in catalysis. The synthesis of amino-dithiaphospholanes was envisaged as an approach to electronically tuned phosphoramidites. General access to a variety of structurally modified amino-dithiaphospholanes from commercially available starting materials was developed. The electron donating properties of the new ligands were characterized by NMR. They were found to be more electron-donating than the corresponding phosphoramidites. The coordination chemistry of amino-dithiaphospholanes was investigated by synthesis of a …

Preparation Of Novel Hydrolyzing Urethane Modified Thiol-Ene Networks, Nicole M. Mackey, Bridget S. Confait, James Wynne, J. Paige Buchanan

Faculty Publications

Novel tetra-functional hydrolyzing monomers were prepared from the reaction of TEOS and select alkene-containing alcohols, ethylene glycol vinyl ether or 2-allyloxy ethanol, and combined with trimethylolpropane tris(3-mercaptopropionate) (tri-thiol) in a thiol-ene “click” polymerization reaction to produce clear, colorless thiol-ene networks using both radiation and thermal-cure techniques. These networks were characterized for various mechanical characteristics, and found to posses T_g’s (DSC), hardness, tack, and thermal stability (TGA) consistent with their molecular structures. A new ene-modified urethane oligomer was prepared based on the aliphatic polyisocyanate Desmodur^® N 3600 and added to the thiol-ene hydrolyzable network series in increasing amounts, …

Fabrication Of Size-Tunable Metallic Nanoparticles Using Plasmid Dna As A Biomolecular Reactor, Jacopo Samson, Irene Piscopo, Alex Yampolski, Patrick Nahirney, Andrea Parpas, Amit Aggarwal, Raihan Saleh, Charles Michael Drain

Publications and Research

Plasmid DNA can be used as a template to yield gold, palladium, silver, and chromium nanoparticles of different sizes based on variations in incubation time at 70 °C with gold phosphine complexes, with the acetates of silver or palladium, or chromium acetylacetonate. The employment of mild synthetic conditions, minimal procedural steps, and aqueous solvents makes this method environmentally greener and ensures general feasibility. The use of plasmids exploits the capabilities of the biotechnology industry as a source of nanoreactor materials.

Vibrational And Electronic Spectra Of 9, 10-Dihydrobenzo (A) Pyren-7 (8h)-One And 7, 8, 9, 10-Tetrahydrobenzo (A) Pyrene: An Experimental And Computational Study [Abstract], Kefa Karimu Onchoke, Prabir K. Dutta, Matthew Parks, Mireya Martinez

Faculty Publications

No abstract provided.

Open Data, Open Source, And Open Standards In Chemistry: The Blue Obelisk Five Years On, Andrew Lang, Noel M. O'Boyle, Rajarshi Guha, Egon Willighagen, Samuel Adams, Jonathan Alvarsson, Jean-Claude Bradley, Igor Filippov, Robert M. Hanson, Marcus D. Hanwell, Geoffrey R. Hutchison, Craig A. James, Nina Jeliazkova, Karol M. Langner, David C. Lonie, Daniel M. Lowe, Jerome Pansanel, Dmitry Pavlov, Ola Spjuth, Christoph Steinbeck, Adam L. Tenderholt, Kevin J. Theisen, Peter Murray-Rust

College of Science and Engineering Faculty Research and Scholarship

Background: The Blue Obelisk movement was established in 2005 as a response to the lack of Open Data, Open Standards and Open Source (ODOSOS) in chemistry. It aims to make it easier to carry out chemistry research by promoting interoperability between chemistry software, encouraging cooperation between Open Source developers, and developing community resources and Open Standards. Results: This contribution looks back on the work carried out by the Blue Obelisk in the past 5 years and surveys progress and remaining challenges in the areas of Open Data, Open Standards, and Open Source in chemistry. Conclusions: We show that the Blue …

Reactive Quenching Of Od A (2)Σ(+) By H-2: Translational Energy Distributions For H- And D-Atom Product Channels, J. H. Lehman, Jesse Lyle Bertrand , '11, Thomas Alex Stephenson, M. I. Lester

Chemistry & Biochemistry Faculty Works

The H- and D-atom products from collisional quenching of OD A (2)Sigma(+) by H-2 are characterized through Doppler spectroscopy using two-photon (2 S-2 <-<- 1 S-2) laser-induced fluorescence. Partial deuteration enables separation of the channel forming H + HOD products, which accounts for 75% of reactive quenching events, from the D + H2O product channel. The Doppler profiles, along with those reported previously for other isotopic variants, are transformed into product translational energy distributions using a robust fitting procedure based on discrete velocity basis functions. The product translational energy distribution for the H- atom channel is strongly peaked at low energy (below 0.5 eV) with a long tail extending to the energetic limit. By contrast, the D-atom channel exhibits a small peak at low translational energy with a distinctive secondary peak at higher translational energy (approximately 1.8 eV) before falling off to higher energy. In both cases, most of the available energy flows into internal excitation of the water products. Similar distributions are obtained upon reanalysis of D- and H- atom Doppler profiles, respectively, from reactive quenching of OH A (2)Sigma(+) by D-2. The sum of the translational energy distributions for H- and D- atom channels is remarkably similar to that obtained for OH A (2)Sigma(+) + H-2, where the two channels cannot be distinguished from one another. The product translational energy distributions from reactive quenching are compared with those obtained from a previous experiment performed at higher collision energy, quasiclassical trajectory calculations of the post-quenching dynamics, and a statistical model. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3644763]

Preparation And Characterization Of A Composite Of Gold Nanoparticles And Single-Walled Carbon Nanotubes And Its Potential For Heterogeneous Catalysis, Anne Shanahan, James Sullivan, Mary Mcnamara, Hugh Byrne

Articles

A single-walled carbon nanotube-supported gold nanoparticle composite was prepared and characterized by X-ray diffraction, scanning transmission electron microscopy/scanning electron microscopy/transmission electron microscopy, energy-dispersive X-ray analysis, atomic absorption spectroscopy, nitrogen adsorption, Raman spectroscopy, and ultraviolet-visible spectroscopy. The Au particles were found to be crystalline, with a well-defined and narrow particle-size distribution, centered around 7 nm. The activity and selectivity of the composite for solventless aerobic oxidation of a secondary alcohol were examined, and a conversion efficiency of 95% was obtained.

Total Synthesis Of 4'-Ester Resveratrol Analogs And 8.9-Amido Geldanamycin Analog And Toward The Total Synthesis Of (-)-Englerin A, Yong Wang

Theses and Dissertations

Total Synthesis of 4'-ester Resveratrol Analogs and 8, 9-amido Geldanamycin Analog and toward the Total Synthesis of (-)-Englerin A Yong Wang Department of Chemistry and Biochemistry, BYU Doctor of Philosophy The phytoalexin resveratrol and its 4'-ester analogs have been prepared with a decarbonylative Heck reaction. The deprotecting step has been modified and improved to increase yield and avoid chromatography. A set of resveratrol analogs and resveratrol have been tested with melanoma and pancreatic cell assays. The 8, 9-amido Geldanamycin analog has been synthesized with a convergent route, involving 28 simplified steps in its longest linear sequence. Synthetic methodologies, such as …

Substrate Binding Modulates The Activity Of Mycobacterium Smegmatis G, A Flavin-Dependent Monooxygenase Involved In The Biosynthesis Of Hydroxamate-Containing Siderophores, Reeder Robinson, Pablo Sobrado

Chemistry Faculty Research & Creative Works

Mycobacterium smegmatis G (MbsG) is a flavin-dependent monooxygenase that catalyzes the NAD(P)H- and oxygen-dependent hydroxylation of the terminal amino group on the side chain of l-lysine in the biosynthetic pathway of the siderophore mycobactin. Mycobactins are essential for mycobacterium growth under iron-limiting conditions encountered during infection in mammals. Thus, enzymes involved in the biosynthesis of mycobactin represent potential drug targets. MbsG was expressed in Escherichia coli and purified using metal affinity and ionic exchange chromatographies. Recombinant MbsG represents the first member of this class of enzymes isolated in the active form, with a tightly bound FAD cofactor. The k cat …

Polycyclic Aromatic Compounds As Anticancer Agents: Evaluation Of Synthesis And In Vitro Cytotoxicity, Debasish Bandyopadhyay, Jose C. Granados, John D. Short, Bimal K. Banik

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Polycyclic aromatic hydrocarbons (PAHs) are considered to be significant environmental carcinogens. Additionally, various planar ring systems are capable of intercalating with DNA, leading to a number of drugs that possess chemotherapeutic activity. In this study, three new polyaromatic compounds with a side chain were synthesized, and spectroscopic as well as elemental analyses were performed. The addition of the long chains to either chrysene or pyrene caused a red-shift in the spectral emission when compared to the corresponding polycyclic aromatic hydrocarbons itself. Furthermore, the cytotoxicity of the three novel polyaromatic compounds was evaluated in vitro in a panel of cultured mammalian …

Distinct Cellular Pools Of Perilipin 5 Point To Roles In Lipid Trafficking, John Tansey

Biology and Earth Science Faculty Scholarship

The PAT family of lipid storage droplet proteins comprised five members, each of which has become an established regulator of cellular neutral lipid metabolism. Perilipin 5 (also known as lsdp-5, MLDP, PAT-1, and OXPAT), the most recently discovered member of the family, has been shown to localize to two distinct intracellular pools: the lipid storage droplet (LD), and a poorly characterized cytosolic fraction. We have characterized the denser of these intracellular pools and find that a population of perilipin 5 not associated with large LDs resides in complexes with a discrete density (~1.15 g/ml) and size (~575 kDa). Using immunofluorescence, …

Chemistry & Biochemistry Newsletter, Department Of Chemistry & Biochemistry, South Dakota State University

Chemistry & Biochemistry Newsletter: 2002-2015

Inside:

Page 2 International Year of Chemistry Recognizes SDSU program

Page 3 Student Research Focuses on Soil Health

Page 4 Medial Laboratory Science Receives Accreditation; Pat Tille is Honored by ASCLS and Alpha Mu Tau

Page 5 Mass Spec Open House; Foundation Donors; Grad Student Chosen NSF Scholar

Page 6 Researcher Featured on SDSU’s Web site; Recent Grants

Page 7 New Graduate Students

Page 8 New Faculty; Alumni Updates

Monitoring The Health Of Glen Helen Nature Preserve: Can I Drink The Water?, David Kammler Ph.D., Triet Minh Truong, Garrett Vanness, Audrey E. Mcgowin Ph.D.

Chemistry Student Publications

This poster presents the results for water quality testing in Glen Helen by the Advanced Environmental Chemistry and Analysis course at Wright State University under the direction of Professor Audrey McGowin and the Global Seminar: Water course at Antioch College under the direction of Professor David Kammler in Fall 2011. Water quality data are presented for the Yellow Spring in Yellow Springs, Ohio for September, October, and November of 2011. Other test sites included Birch Creek and other sites along Yellow Springs Creek.

This poster was created and presented at the 3rd Annual Wright State University Campus-Wide Celebration of Research, …

6-[(4-Hydroxyphenyl)Diazenyl]- 1,10-Phenanthrolin-1-Ium Chloride Monohydrate, Akram Hazeen, Yan Zhang, Minchong Mao, Kraig A. Wheeler, Mark E. Mcguire

Faculty Research and Creative Activity

In the cation of the title molecular salt, C18H13N4O+_Cl__H2O, the dihedral angle between the mean planes of the 1,10- phenanthroline system and the phenol ring is 14.40 (19)_. The crystal packing is stabilized by O—H_ _ _O hydrogen bonds, weak N—H_ _ _Cl and O—H_ _ _Cl intermolecular interactions and _—_ stacking interactions [centroid–centroid distance = 3.6944 (13) and 3.9702 (12) [A °]

Excellent Adventures In Global Collaboration, Glenn W. "Max" Mcgee, Aracelys Rios

Publications & Research

No abstract provided.

Computational Studies Of Ion Transport In Polymer Electrolytes, Hui Wu

Doctoral Dissertations

Improving ionic conductivity and lithium mobility in polymer electrolytes is important for their practical use for battery electrolytes. In this study, a combination of molecular dynamics and Monte Carlo simulations was used to bring insight into lithium ion transport in poly(ethylene oxide) (PEO) with plasticizers and also next to alumina solid surface doped with lithium salt. The simulations were performed using a moderately high molecular weight polymer (Mn = 10,000 g/mol) at an EO:Li ratio of 15. For the plasticized system, the PEO with LiN(CF3SO 2)2 (LiTFSI) was mixed with 10 wt% plasticizers that included either cyclic ethylene carbonate …

Photoinduced Electron Transfer In Naphthalimide-Pyridine Systems: Effect Of Proton Transfer On Charge Recombination Efficiencies, Pavel Kucheryavy, Renat Khatmullin, Ekaterina Mirzakulova, Dapeng Zhou, Ksenija D. Glusac

Chemistry Faculty Publications

We studied the effect of proton-coupled electron transfer on lifetimes of the charge-separated radicals produced upon light irradiation of the thiomethyl-naphthalimide donor SMe-NI-H in the presence of nitro-cyano-pyridine acceptor (NO(2)-CN-PYR). The dynamics of electron and proton transfer were studied using femtosecond pump-probe spectroscopy in the UV/vis range. We find that the photoinduced electron transfer between excited SMe-NI-H and NO(2)-CN-PYR occurs with a rate of 1.1 x 10(9) s(-1) to produce radical ions SMe-NI-H(center dot+) and NO(2)-CN-PYR(center dot-). These initially produced radical ions in a solvent cage do not undergo a proton transfer, possibly due to unfavorable geometry between N-H proton …

Noncanonical Hydrogen Bonding In Nucleic Acids. Benchmark Evaluation Of Key Base–Phosphate Interactions In Folded Rna Molecules Using Quantum-Chemical Calculations And Molecular Dynamics Simulations, Marie Zgarbova, Petr Jurecka, Pavel Banas, Michal Otyepka, Judit E. Sponer, Neocles B. Leontis, Craig L. Zirbel, Jiri Sponer

Chemistry Faculty Publications

RNA molecules are stabilized by a wide range of non canonical interactions that are not present in DNA. Among them, the recently classified base phosphate (BPh) interactions belong to the most important ones. Twelve percent of nucleotides in the ribosomal crystal structures are involved in BPh interactions. BPh interactions are highly conserved and provide major constraints on RNA sequence evolution. Here we provide assessment of the energetics of BPh interactions using MP2 computations extrapolated to the complete basis set of atomic orbitals and corrected for higher-order electron correlation effects. The reference computations are compared with DFT-D and DFT-D3 approaches, the …

Development, Kinetic Analysis And Applications Of 2-D Nanostructured Layered Metal Hydroxides, Stephen Majoni

Dissertations (1934 -)

Nanodimensional layered metal hydroxides which include layered hydroxy salts (LHSs) and hydroxy double salts (HDSs) have the ability to accommodate species between the layers. The structural composition of these materials can be tuned so as to create materials with targeted physico-chemical properties for applications where it is advantageous to intercalate or release molecules. Some of the applications include ion-exchange, fire retardation, catalysis, and controlled release delivery. Anion exchange reactions are among methods used to optimize these materials for targeted applications, making the characterization of exchange kinetics of practical interest. In addition, understanding fundamental factors that control retention and release of …

An Lcms Based Assay For Detection And Quantification Of Bacterial Cell Wall Intermediates, Chandra Sekhar Arigapudi

All Capstone Projects

The main objective of my project is to determine the bacterial cell wall intermediates in E.coli and develop an LCMS method that Phosphomycin is a PEP analogue that irreversibly inhibits UDP-GluNAc-enolpyruvate transferase (MurA enzyme), which prevents the formation of N-acetyl muramic acid, which is an essential element in the Peptidoglycan cell wall. Antibacterial agents have a tremendous impact on human health. Most of the antibacterial agents, including beta lactams target the bacterial cell wall biosynthesis.The pathway for Escherichia coli is shown in page 19. Among the most widely used antibiotics, beta lactams inhibit the penicillin binding protein (PBPs)which block the …

Evaluation And In Vitro Studies Of Folate Peg Biotin And Other Peg Agents, Vikram Reddy Kasarala

All Capstone Projects

Folate is an essential component for cell growth and cell division, playing a major role in DNA synthesis. It is common sense that the rapidly dividing cells synthesize more DNA, including cancer cells. Also, it was reported that cancer cells over express Folate receptors and this was the basis for our probe for cancer cells. We used long PEG biotin in conjugation with Folate. Previous studies in our group showed that the PEG could be used in the sensor to detect and capture cancer cells. The present study was aimed at evaluating the effect of Long PEG containing Folate based …

Evaluation And In Vitro Studies Of Folate Peg Biotin And Other Peg Agents, Christopher E. Zmudka

All Capstone Projects

Folate receptor alpha is a membrane-bound protein displaying high affinity for folic acid. This receptor is believed to serve as a receptor-mediated transport system of folic acid into cancer and cells associated with inflammation. Interesting, most normal cells in the body have little if no high affinity folate receptor alpha. Based on these attributes, folate based drug delivery, imaging systems, and diagnostic systems are in several stages of development worldwide.

Numerous methods have been explored in the literature in an attempt to detect low levels of free folate receptor and/or rare circulating cancer cells. In an attempt to further exploit …

Nanoparticles For Mercury Abatement, Sunil Krishna Thanikanti

All Capstone Projects

Mercury is considered to be a global contaminant. It does not break down in the environment and can build up in living organisms. Mercury can be carried long distances on wind currents, staying in the atmosphere for long periods of time, when in its vapor form. High mercury exposure results in permanent nervous system and kidney damage. Mercury exists in three different chemical forms: elemental, inorganic, and organic. The routes of exposure can be inhalation, ingestion, or skin contact. Vapor from liquid elemental mercury and methyl mercury are more easily absorbed than inorganic mercury salts and can, therefore, cause more …

Wound Healing And The Role Of Biomarkers And Biofilms, Mujtaba Khan

All Capstone Projects

An injury to the skin alters the integrity of underlying tissues and microcirculation and thus certainly culminates in a wound. Wound healing is a highly complex, dynamic, interactive and well regulated physiological process involving blood cells, extracellular matrix, parenchyma cells and soluble mediators. It starts with alteration in integrity of tissues and ends with the formation of scar. The process of wound healing is distinguished into Haemostasis, Inflammation, Proliferation and Remodeling. Various cells like platelets, neutrophils, macrophages, lymphocytes, angiocytes, keratinocytes, fibroblasts and factors like platelet derived growth factor, transforming growth factor, platelet derived epidermal growth factors, fibroblasts growth factor, albumin, …

Layer-By-Layer Fabrication Of Covalently Crosslinked And Reactive Polymer Multilayers Using Azlactone-Functionalized Copolymers: A Platform For The Design Of Functional Biointerfaces, Maren E. Buck, David M. Lynn

Chemistry: Faculty Publications

We report a method for modulating the physicochemical properties of surfaces that is based on the reactive layer-by-layer fabrication of covalently crosslinked thin films using azlactone-functionalized copolymers. We demonstrate that copolymers containing different molar ratios of methyl methacrylate (MMA) and 2-vinyl-4,4-dimethylazlactone (VDMA) can be alternately deposited with poly(ethyleneimine) to assemble covalently crosslinked thin films. Characterization using ellipsometry demonstrates that, in general, film growth and thickness decrease as the content of reactive, azlactone functionality in the copolymer used to assemble the film decreases. Reflective infrared spectroscopy experiments demonstrate that films fabricated from MMA:VDMA copolymers contain residual azlactone functionality and that these …

Analytical Evaluation Of Imaging Agents, Vineela Chowdary Talluri

All Capstone Projects

The folate receptor has achieved great importance for use in targeted drug delivery and in vitro and in vivo diagnostic assays. The folate receptor (FR) is over expressed on several cancer cell types and activated macrophages, but exists in relatively low abundance on the surface of non-cancerous tissue and non inflammatory cells. This unique attribute is the hallmark of folate – targeted methodologies allowing the diagnostic agent and/or drug to be ferried to the specific disease sites while preventing “off target” effects in normal tissues. Although several folate-based dyes have been reported, simple and detailed synthetic and purification methods for …

Capture And Analysis Of Cells Using Magnetic Beads, Alexandro Dominguez

All Capstone Projects

Magnetic separation of cells and bacterium is a fascinating field of study. There are tremendous capabilities in separation, selectivity, and sensitivity. Magnetic separation reduces complex techniques, time consuming preparation, and complicated multistep methods of separation.The separation of cells, bacterium, and macromolecules can be extremely challenging. Fortunately, magnetically tagged cells, bacterium and macromolecules can be easily separated without great expertise. Antibody magnetic micro beads are specific to a cell, bacterium, or macromolecules. Separating a mixture can lead to a better, more accurate analysis of samples that can be crucial in the medical field, therapeutic drug delivery systems, and in some circumstances …

Cloudy And Starry Milia-Like Cysts: How Well Do They Distinguish Seborrheic Keratoses From Malignant Melanomas?, S. M. Stricklin, William V. Stoecker, M. C. Oliviero, H. S. Rabinovitz, S. K. Mahajan

Chemistry Faculty Research & Creative Works

Background Seborrheic keratoses are the most common skin lesions known to contain small white or yellow structures called milia-like cysts (MLCs). Varied appearances can sometimes make it difficult to differentiate benign lesions from malignant lesions such as melanoma, the deadliest form of skin cancer found in humans. Objective the purpose of this study was to determine the statistical occurrence of MLCs in benign vs. malignant lesions. Methods a medical student with 10 months experience in examining approximately 1000 dermoscopy images and a dermoscopy-naïve observer analyzed contact non-polarized dermoscopy images of 221 malignant melanomas and 175 seborrheic keratoses for presence of …

A Modified Stokes-Einstein Equation For A Beta Aggregation, Srisairam Achuthan, Bong Jae Chung, Preetam Ghosh, Vijayaraghavan Rangachari, Ashwin Vaidya

Faculty Publications

Background: In all amyloid diseases, protein aggregates have been implicated fully or partly, in the etiology of the disease. Due to their significance in human pathologies, there have been unprecedented efforts towards physiochemical understanding of aggregation and amyloid formation over the last two decades. An important relation from which hydrodynamic radii of the aggregate is routinely measured is the classic Stokes-Einstein equation. Here, we report a modification in the classical Stokes-Einstein equation using a mixture theory approach, in order to accommodate the changes in viscosity of the solvent due to the changes in solute size and shape, to implement a …

Fluorescence Probes For Cellular Thiol And Disulfide Detection: Sythesis And Biophysical Characterization, Timothy Jonhera

Dissertations (1934 -)

The total concentration of cellular thiols is about 30 mM, and use of current fluorescent chemical probes to quantitate these thiols inside cells is impractical. We recently reported fluorescent dithio probes (donor-S-S-acceptor, DSSA) with unusually low reduction potential (- 0.6 V) that can detect changes in intracellular thiols and cross membranes of bacterial and mammalian cells, but they could not quantify thiol redox state. Here we report a new variant of the DSSA series, which has hydroxy coumarin (Ex: 320 nm, Em: 460 nm) as donor and fluorescein (Ex: 485 nm, Em: 520 nm) as acceptor. The probe was characterized …