Chemistry Commons^™

Identifying Medication Targets For Psychostimulant Addiction: Unraveling The Dopamine D3 Receptor Hypothesis, Thomas M. Keck, William S. John, Paul W. Czoty, Michael A. Nader, Amy Hauck Newman

College of Science & Mathematics Departmental Research

The dopamine D3 receptor (D3R) is a target for developing medications to treat substance use disorders. D3R-selective compounds with high affinity and varying efficacies have been discovered, providing critical research tools for cell-based studies that have been translated to in vivo models of drug abuse. D3R antagonists and partial agonists have shown especially promising results in rodent models of relapse-like behavior, including stress-, drug-, and cue-induced reinstatement of drug seeking. However, to date, translation to human studies has been limited. Herein, we present an overview and illustrate some of the pitfalls and challenges of developing novel D3R-selective compounds toward clinical …

Optimizing Metallization Of Dna-Templated Nanostructures, Andrew Dearden, Adam Woolley

Journal of Undergraduate Research

With countless technologies that rely on microprocessors, there is a great need for increasingly smaller microelectronic components. Traditionally, manufacturers have employed a “top-down” approach to build microelectronics – that is, they have attempted to scale functional microcircuitry components down in size, hoping for similar performance in a smaller circuit. This top-down approach is expensive, often costing manufacturers hundreds of dollars per part. A much more cost-effective approach to microelectronics has emerged over the past decade in the field of molecular science: that is, to develop circuitry from the “bottom-up” using macromolecules such as deoxyribonucleic acid (DNA). Scientists have now devised …

Immunoassays Of Potential Cancer Biomarkers In Microfluidic Devices, Jayson Virola Pagaduan

Theses and Dissertations

Laboratory test results are important in making decisions regarding a patient's diagnosis and response to treatment. These tests often measure the biomarkers found in biological fluids such blood, urine, and saliva. Immunoassay is one type of laboratory test used to measure the level of biomarkers using specific antibodies. Microfluidics offer several advantages such as speed, small sample volume requirement, portability, integration, and automation. These advantages are motivating to develop microfluidic platforms of conventional laboratory tests. I have fabricated polymer microfluidic devices and developed immunoassays on-chip for potential cancer markers. Silicon template devices were fabricated using standard photolithographic techniques. The template …

Polycyclic Aromatic Hydrocarbon Determination In Liver Of Menhaden Exposed To The Deep Water Horizon Oil Spill, Rebecca Hawke

Seton Hall University Dissertations and Theses (ETDs)

The April 2010 BP® oil spill has caused great concern for ecological impacts in the Gulf of Mexico. Crude oil contains polycyclic aromatic hydrocarbon (PAHs) and oil spills increase the exposure of aquatic organisms to this class of chemicals. The overall detrimental health effects associated with PAH exposure depend on the exposure period, the concentration of PAHs, and the toxicity of the PAHs in the mixture. Brevoortia tyrannus and Brevoortia patronus are filter feeding fish commonly known as menhaden and account for over 40% of the commercial industry fisheries catch. As primary consumers, they are a major link in the …

Aldehydic C-H Amination Reactions Via Co(Ii)-Based Metalloradical Catalysis And Construction Of Novel Chiral Meso-Amidoporphyrin Ligands, Christopher Lee Lizardi

USF Tampa Graduate Theses and Dissertations

Medium-sized organic ring synthesis poses a seemingly insurmountable challenge, and because of this it is a field under immense investigation. Heterocyclic containing medium-sized rings are common structural motifs in nature, which has caused researchers to investigate their potential biological activity and properties as materials. This research focused on the grand challenge of medium-sized heterocyclic ring synthesis, providing the synthesis community with new tools to generate these highly evasive products, while elucidating energetic and geometric properties of one of Nature's least understood organic ring systems.

Cobalt(II)-Amidoporphyrins, [Co(D₂-Por)], are an emerging class of metalloradical catalysts (MRC) which can facilitate …

Optical Laser-Induced Co Desorption From Ru(0001) Monitored With A Free-Electron X-Ray Laser: Dft Prediction And X-Ray Confirmation Of A Precursor State, H. Öberg, J. Gladh, M. Dell'angela, T. Anniyev, M. Beye, R. Coffee, A. Föhlisch, T. Katayama, S. Kaya, Jerry L. Larue, A. Møgelhøj, D. Nordlund, H. Ogasawara, W. F. Schlotter, J. A. Sellberg, F. Sorgenfrei, J. J. Turner, M. Wolf, W. Wurth, H. Öström, A. Nilsson, J. K. Nørskov, L. G. M. Pettersson

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We present density functional theory modeling of time-resolved optical pump/X-ray spectroscopic probe data of CO desorption from Ru(0001). The BEEF van der Waals functional predicts a weakly bound state as a precursor to desorption. The optical pump leads to a near-instantaneous (< 100 fs) increase of the electronic temperature to nearly 7000 K. The temperature evolution and energy transfer between electrons, substrate phonons and adsorbate is described by the two-temperature model and found to equilibrate on a timescale of a few picoseconds to an elevated local temperature of ~ 2000 K. Estimating the free energy based on the computed potential of mean force along the desorption path, we find an entropic barrier to desorption (and by time-reversal also to adsorption). This entropic barrier separates the chemisorbed and precursor states, and becomes significant at the elevated temperature of the experiment (~ 1.4 eV at 2000 K). Experimental pump-probe X-ray absorption/X-ray emission spectroscopy indicates population of a precursor state to desorption upon laser-excitation of the system (Dell'Angela et al., 2013). Computing spectra along the desorption path confirms the picture of a weakly bound transient state arising from ultrafast heating of the metal substrate.

L-Lactide And Ε-Caprolactone Ring Opening Polymerization By Binary Catalysts Systems That Include Bis-Ligated Magnesium Complexes, Reile M. Slattery, Arnold L. Rheingold, Joseph M. Fritsch

Seaver College Research And Scholarly Achievement Symposium

A series of bis-ligated magnesium complexes supported by tridentate ketoiminates containing electron-donating and electron-withdrawing groups were prepared. The complexes were characterized with ¹H, ¹³C, and ¹⁹F NMR, absorbance spectroscopy, and x-ray crystallography. The complexes were assessed for their ring opening polymerization activity with L-lactide (L-lac) and ϵ-caprolactone (eCL) in binary catalyst systems with 4-fluorophenol at 100 °C. The magnesium complexes supported by ketoiminates bearing electron-donating groups yielded greater percentage conversions from monomers to polymers than those containing electron-withdrawing groups for both L-lac and eCL. The magnesium complexes were more efficient at polymerizing L-lac than eCL, and …

Helicobacter Pylori Flha Binds The Sensor Kinase And Flagellar Gene Regulatory Protein Flgs With High Affinity, Jennifer Tsang, Takanori Hirano, Timothy R. Hoover, Jonathan L. Mcmurry

Faculty Articles

Flagellar biogenesis is a complex process that involves multiple checkpoints to coordinate transcription of flagellar genes with the assembly of the flagellum. In Helicobacter pylori, transcription of the genes needed in the middle stage of flagellar biogenesis is governed by RpoN and the two-component system consisting of the histidine kinase FlgS and response regulator FlgR. In response to an unknown signal, FlgS autophosphorylates and transfers the phosphate to FlgR, initiating transcription from RpoNdependent promoters. In the present study, export apparatus protein FlhA was examined as a potential signal protein. Deletion of its N-terminal cytoplasmic sequence dramatically decreased expression of two …

Applied Quantum Chemistry: Spectroscopic Detection And Characterization Of The F2Bs And Cl2Bs Free Radicals In The Gas Phase, Bing Jin, Phillip M. Sheridan, Dennis J. Clouthier

Chemistry Faculty Publications

In this and previous work [D. J. Clouthier, J. Chem. Phys. 141, 244309 (2014)], the spectroscopic signatures of the X₂BY (X = H, halogen, Y = O, S) free radicals have been predicted using high level ab initio theory. The theoretical results have been used to calculate the electronic absorption and single vibronic level (SVL) emission spectra of the radicals under typical jet-cooled conditions. Using these diagnostic predictions, the previously unknown F₂BS and Cl₂BS free radicals have been identified and characterized. The radicals were prepared in a free jet expansion by subjecting precursor …

Determination Of Abraham Model Solute Descriptors For The Monomeric And Dimeric Forms Of Trans-Cinnamic Acid Using Measured Solubilities From The Open Notebook Science Challenge, Andrew Lang, Jean-Claude Bradley, Michael H. Abraham, William E. Acree Jr., Samantha N. Beck, David A. Bulger, Elizabeth A. Clark

College of Science and Engineering Faculty Research and Scholarship

Background: Calculating Abraham descriptors from solubility values requires that the solute have the same form when dissolved in all solvents. However, carboxylic acids can form dimers when dissolved in non-polar solvents. For such compounds Abraham descriptors can be calculated for both the monomeric and dimeric forms by treating the polar and non-polar systems separately. We illustrate the method of how this can be done by calculating the Abraham descriptors for both the monomeric and dimeric forms of trans-cinnamic acid, the first time that descriptors for a carboxylic acid dimer have been obtained. Results: Abraham descriptors were calculated for the monomeric …

Predicting Abraham Model Solvent Coefficients, Andrew Lang, Jean-Claude Bradley, Michael H. Abraham, William E. Acree Jr.

College of Science and Engineering Faculty Research and Scholarship

Background: The Abraham general solvation model can be used in a broad set of scenarios involving partitioning and solubility, yet is limited to a set of solvents with measured Abraham coefficients. Here we extend the range of applicability of Abraham’s model by creating open models that can be used to predict the solvent coefficients for all organic solvents. Results: We created open random forest models for the solvent coefficients e, s, a, b, and v that had out-of-bag R2 values of 0.31, 0.77, 0.92, 0.47, and 0.63 respectively. The models were used to suggest sustainable solvent replacements for commonly used …

Violacein Induces P44/42 Mitogen-Activated Protein Kinase‑Mediated Solid Tumor Cell Death And Inhibits Tumor Cell Migration, Toral Mehta, Koen P. Vercruysse, Terrance Johnson, Anthony Okechukwu Ejiofor, Elbert Myles, Quincy A. Quick

Chemistry Faculty Research

Microbial secondary metabolites have emerged as alternative novel drugs for the treatment of human cancers. Violacein, a purple pigment produced by Chromobacterium violaceum, was investigated in the present study for its anti‑tumor properties in tumor cell lines. Clinically applicable concentrations of violacein were demonstrated to inhibit the proliferative capacity of tumor cell lines according to a crystal violet proliferation assay. The underlying mechanism was the promotion of apoptotic cell death, as indicated by poly(ADP ribose) polymerase cleavage and p44/42 mitogen‑activated protein kinase signaling determined by western blot analysis. Collectively, this provided mechanistic evidence that violacein elicits extracellular-signal regulated kinase‑induced apoptosis …

Development Of An Optical Method For The Detection Of Homocysteine As A Disease Biomarker Using Fluorescein-Aldehydes, Aabha Barve

Dissertations and Theses

Homocysteine is a natural occurring aminothiol. It is an intermediate product in the metabolism of methionine. Methionine is an essential amino acid required for protein synthesis. Metabolic irregularities disrupt homocysteine levels in plasma. Elevated homocysteine levels are directly linked to folate and cobalamin (vitamin B12) deficiencies, and are an independent risk factor for cardiovascular diseases. High homocysteine levels have also been associated with Alzheimer's, osteoporosis, renal failure, cancer, birth defects and pregnancy complications. The association of elevated homocysteine levels with cardiovascular disease and other diseases has generated great interest in the detection of homocysteine.

An optical method for the detection …

Structural Patterns At All Scales In A Nonmetallic Chiral Au_133(Sr)_52 Nanoparticle, Chenjie Zeng, Yuxiang Chen, Kristin Kirschbaum, Kannatassen Appavoo, Matthew Y. Sfeir, Rongchao Jin

Publications and Research

Structural ordering is widely present in molecules and materials. However, the organization of molecules on the curved surface of nanoparticles is still the least understood owing to the major limitations of the current surface characterization tools. By the merits of x-ray crystallography, we reveal the structural ordering at all scales in a super robust 133–gold atom nanoparticle protected by 52 thiolate ligands, which is manifested in self-assembled hierarchical patterns starting from the metal core to the interfacial –S–Au–S– ladder-like helical “stripes” and further to the “swirls” of carbon tails. These complex surface patterns have not been observed in the smaller …

Supramolecular Chemistry For Undergraduate Students, David V. Dearden, Roger G. Harrison

Journal of Undergraduate Research

The goal of this proposal was to train graduate and undergraduate students through research experiences in supramolecular chemistry in a multi-group environment. Academically, our objective was to synthesize and characterize new supramolecular host molecules and to develop applications for these molecules. We believe we have been quite successful, as demonstrated by the presentations and publications listed below and as shown by the receipt of a National Science Foundation grant by one of the teams involved in this research, in a year when such grants were particularly difficult to obtain.

Byu Meg Report, Emily Bates

Journal of Undergraduate Research

The academic objectives were met by the proposal. Students learned to sequence DNA and to interpret the sequence to know if there was a rare genetic change occurring in the sequence that they interpreted. Students learned to write academic abstracts, introductions, results, and conclusions in the format of an academic journal. Furthermore, together the students determined that the genetic change in a family with an inherited syndrome of birth defects was not one that had previously been identified or described.

Mentoring Undergraduates Via Organic Synthesis, Steven L. Castle

Journal of Undergraduate Research

This report summarizes the results that were generated under the auspices of the mentoring environment in my laboratory from January 2013 to the present. A total of eight undergraduates participated in the mentoring environment during this period.

Capillary Effects In Guided Crystallization Of Organic Thin Films, Alta Fang, Anna K. Hailey, Abigail Grosskopf, John E. Anthony, Yueh-Lin Loo, Mikko Haataja

Chemistry Faculty Publications

Recently, it has been demonstrated that solvent-vapor-induced crystallization of triethylsilylethynyl anthradithiophene (TES ADT) thin films can be directed on millimeter length scales along arbitrary paths by controlling local crystal growth rates via pre-patterning the substrate. Here, we study the influence of capillary effects on crystallization along such channels. We first derive an analytical expression for the steady-state growth front velocity as a function of channel width and validate it with numerical simulations. Then, using data from TES ADT guided crystallization experiments, we extract a characteristic channel width, which provides the smallest feature size that can be obtained by this technique.

Parmodulins Inhibit Thrombus Formation Without Inducing Endothelial Injury Caused By Vorapaxar, Omozuanvbo Aisiku, Christian G. Peters, Karen De Ceunynck, Chandra C. Ghosh, James R. Dilks, Susanna F. Fustolo-Gunnink, Mingdong Huang, Chris Dockendorff, Samir M. Parikh, Robert Flaumenhaft

Chemistry Faculty Research and Publications

Protease-activated receptor-1 (PAR1) couples the coagulation cascade to platelet activation during myocardial infarction and to endothelial inflammation during sepsis. This receptor demonstrates marked signaling bias. Its activation by thrombin stimulates prothrombotic and proinflammatory signaling, whereas its activation by activated protein C (APC) stimulates cytoprotective and antiinflammatory signaling. A challenge in developing PAR1-targeted therapies is to inhibit detrimental signaling while sparing beneficial pathways. We now characterize a novel class of structurally unrelated small-molecule PAR1 antagonists, termed parmodulins, and compare the activity of these compounds to previously characterized compounds that act at the PAR1 ligand–binding site. We find that parmodulins target …

Sequence-Specific, Nanomolar Peptide Binding Via Cucurbit[8]Uril-Induced Folding And Inclusion Of Neighboring Side Chains, Lauren C. Smith, David G. Leach, Brittney E. Blaylock, Omar A. Ali, Adam R. Urbach

Chemistry Faculty Research

This paper describes the molecular recognition of the tripeptide Tyr-Leu-Ala by the synthetic receptor cucurbit[8]uril (Q8) in aqueous buffer with nanomolar affinity and exceptional specificity. This combination of characteristics, which also applies to antibodies, is desirable for applications in biochemistry and biotechnology but has eluded supramolecular chemists for decades. Building on prior knowledge that Q8 binds to peptides with N-terminal aromatic residues, a library screen of 105 peptides was designed to test the effects of residues adjacent to N-terminal Trp, Phe, or Tyr. The screen used tetramethylbenzobis(imidazolium) (MBBI) as a fluorescent indicator and resulted in the unexpected discovery that MBBI …

Structure-Function Relationships Affecting The Sensing Mechanism Of Monolayer-Protected Cluster Doped Xerogel Amperometric Glucose Biosensors, Luke T. Dipasquale, Nicholas G. Poulos, Jackson R. Hall, Aastha Minocha, Tram Anh Bui, Michael C. Leopold

Chemistry Faculty Publications

A systematic study of the structure–function relationships critical to understanding the sensing mechanism of 1st generation amperometric glucose biosensors with an embedded nanoparticle (NP) network is presented. Xerogel-based films featuring embedded glucose oxidase enzyme and doped with alkanethiolate-protected gold NPs, known as monolayer protected clusters (MPCs), exhibit significantly enhanced performance compared to analogous systems without NPs including higher sensitivity, faster response time, and extended linear/dynamic ranges. The proposed mechanism involves diffusion of the glucose to glucose oxidase within the xerogel, enzymatic reaction production of H2O2 with subsequent diffusion to the embedded network of MPCs where it is oxidized, an event …

Facile Methods For The Analysis Of Lysophosphatidic Acids In Human Plasma, Jialu Wang

Dissertations and Theses

Lysophosphatidic acid (LPA) influences many physiological processes, such as brain and vascular development. It is associated with several diseases including ovarian cancer, breast cancer, prostate cancer, colorectal cancer, hepatocellular carcinoma, multiple myeloma atherosclerotic diseases, cardiovascular diseases, pulmonary inflammatory diseases and renal diseases. LPA plasma and serum levels have been reported to be important values in diagnosing ovarian cancer and other diseases. However, the extraction and quantification of LPA in plasma are very challenging because of the low physiological concentration and similar structures of LPA to other phospholipids. Many previous studies have not described the separation of LPA from other phospholipids, …

Photophysics Of Organic Semiconductors: From Ensemble To The Single-Molecule Level, Rebecca Grollman, Whitney E. B. Shepherd, Alexander Robertson, Keshab R. Paudel, John E. Anthony, Oksana Ostroverkhova

Chemistry Faculty Publications

We present photophysical properties of functionalized anthradithiophene (ADT) and pentacene (Pn) derivatives, as well as charge and energy transfer properties of donor-acceptor (D/A) pairs of these derivatives. All molecules studied were fluorescent and photostable enough to be imaged on the single-molecule level in a variety of polymeric and in a functionalized benzothiophene (BTBTB) crystalline host using room-temperature wide- field epifluorescence microscopy. Flexibility of functionalization of both guest (ADT, Pn) and host (BTBTB or polymer) molecules can be used for systematic studies of nanoscale morphology and photophysics of D/A organic semiconductor bulk heterojunctions, as well as in applications relying on FRET, …

Spectroscopy, Nmr, And Electrochemistry Studies Of Protonated Aminophenyl/Pyridyl Porphyrins And Their Application In Hydrogen Evolution, Chenyi Wang

Dissertations and Theses

Spectrophotometric titrations for a full series of 4-aminophenyl/4-pyridyl meso-substituted porphyrins were carried out using methanesulfonic acid in DMSO to study the hyperporphyrin effect across different substitution patterns. The series included zero, one, two (cis and trans), three, and four meso(4-aminophenyl) groups, with the remaining meso substituents being 4-pyridyl groups. The peripheral pyridyl groups consistently protonate before the interior porphyrin pyrrole nitrogens, which protonate before the aminophenyl groups. Aminophenyl substituents increase the basicity of the pyrrole nitrogens and lead to distinctive hyperporphyrin spectra with a broad Soret band and a strong red absorption. The structure proposed to give rise to these …

The Detection And Quantitative Analysis Of Endocannabinoids And Endogenous Fatty Acid Amides In Apis Mellifera And Tribolium Castaneum, Perry Robert Mitchell Jr.

USF Tampa Graduate Theses and Dissertations

Endocannabinoids, and the fatty acid amides from which they are a member, have garnered greater scientific interest in the last two decades due to the cannabimimetic properties of these endogenous molecules. The most well-known of these is Anandamide, which has thus far been discovered in several species of animal ranging from C. elegans, fruit flies, to bovine and humans. Because of the importance and increasing impact of these compounds a brief overview is first presented herein, with a major focus on the N-acyldopamines due to the direct impact they potentially pose to human physiology.

Secondly, the detection and …

Chemistry And Biochemistry News, Georgia Southern University

Biochemistry, Chemistry & Physics: News & Publications (2012-2023)

• Faculty Highlight: Ji Wu

Chemistry And Biochemistry News, Georgia Southern University

Biochemistry, Chemistry & Physics: News & Publications (2012-2023)

• Faculty Highlight: John Stone

Addressing The Achievement Gap: Engaging Students In The Chemistry Classroom, Haidy Kamel Dr.

Cleveland State University Regional Chemistry Teaching Symposium: March 12 & 13, 2015

No abstract provided.

Magical Science: Chemistry Magic Tricks Just For Fun! (Workshop), Regan L. Silvestri

Cleveland State University Regional Chemistry Teaching Symposium: March 12 & 13, 2015

Chemistry magic tricks are simply chemistry demonstrations cleverly performed, and are highly valuable for engaging and motivating students in the study of chemistry. Our agenda has been to adapt common chemistry demonstrations into presentations with clever twists, essentially turning them into magic tricks. This workshop will show how a science demonstration can be turned into a science magic trick simply by adapting the presentation. Science magic tricks provide a unique forum not only for expanding scientific knowledge, but moreover scientific interest. Our hope is that students will be engaged and motivated in the future study of chemistry.

Electronic And Structural Elements That Regulate The Excited-State Dynamics In Purine Nucleobase Derivatives, Carlos E. Crespo-Hernández, Christian Reichardt, Marvin Pollum

Faculty Scholarship

The excited-state dynamics of the purine free base and 9-methylpurine are investigated using experimental and theoretical methods. Femtosecond broadband transient absorption experiments reveal that excitation of these purine derivatives in aqueous solution at 266 nm results primarily in ultrafast conversion of the S2(ππ∗) state to the vibrationally excited ¹nπ∗ state. Following vibrational and conformational relaxation, the ¹nπ∗ state acts as a doorway state in the efficient population of the triplet manifold with an intersystem crossing lifetime of hundreds of picoseconds. Experiments show an almost 2-fold increase in the intersystem crossing rate on going from polar aprotic to nonpolar …