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2009

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Full-Text Articles in Physical Sciences and Mathematics

Detection Of Psilocybin Mushroom Analogs In Chocolate: Incorporating Current Events Into The Undergraduate Teaching Laboratory, Brandon Huskins, Christopher Dockery Dec 2009

Detection Of Psilocybin Mushroom Analogs In Chocolate: Incorporating Current Events Into The Undergraduate Teaching Laboratory, Brandon Huskins, Christopher Dockery

Faculty and Research Publications

In this experiment, tryptamine is used as a psilocin analog and is dispersed onto a Fisher brand cellulose laboratory sponge to simulate dehydrated mushrooms. The resulting “mushroom” material is ground, molded into chocolate, and presented to student groups for real-world and applied analyses. Students isolate the tryptamine from the chocolate using their knowledge of drug chemistry, solubility, pH, extractions, etc. Qualitative analysis is conducted by comparison to standards (Thin Layer Chromatography or Gas Chromatography) and quantitative analysis is conducted by Gas Chromatography using the method of internal standards.


Highly Nitrated Cyclopropanes As New High Energy Materials: Dft Calculations On The Properties Of C3H6−N(No2)N (N=3–6), Aloysus K. Lawong, David W. Ball Dec 2009

Highly Nitrated Cyclopropanes As New High Energy Materials: Dft Calculations On The Properties Of C3H6−N(No2)N (N=3–6), Aloysus K. Lawong, David W. Ball

Chemistry Faculty Publications

As part of a continuing study of new potential high energy materials, here we present results of calculations on cyclopropane molecules with three or more nitro groups. DFT calculations suggest that all molecules can exist as minimum-energy stationary states. Energy calculations indicate that some nitrocyclopropanes have a specific enthalpy of decomposition in excess of 8kJg−1, suggesting that they be explored as new potential high energy materials.


Indirect Gravimetric Determination Of Waters Of Hydration, Marina C. Koether Dec 2009

Indirect Gravimetric Determination Of Waters Of Hydration, Marina C. Koether

Faculty and Research Publications

An alternate gravimetric experiment is described that can be employed in the general chemistry or the quantitative analysis laboratory course. The procedure takes less time than conventional methods and introduces students to waters of hydration and indirect determinations.


Double Superhelix Model Of High Density Lipoprotein, Zhiping Wu, Valentin Gogonea, Xavier Lee, Mathew A. Wagner Dec 2009

Double Superhelix Model Of High Density Lipoprotein, Zhiping Wu, Valentin Gogonea, Xavier Lee, Mathew A. Wagner

Chemistry Faculty Publications

High density lipoprotein (HDL), the carrier of so-called “good” cholesterol, serves as the major athero-protective lipoprotein and has emerged as a key therapeutic target for cardiovascular disease. We applied small angle neutron scattering (SANS) with contrast variation and selective isotopic deuteration to the study of nascent HDL to obtain the low resolution structure in solution of the overall time-averaged conformation of apolipoprotein AI (apoA-I) versus the lipid (acyl chain) core of the particle. Remarkably, apoA-I is observed to possess an open helical shape that wraps around a central ellipsoidal lipid phase. Using the low resolution SANS shapes of the protein …


Selective Complexation And Reactivity Of Metallic Nitride And Oxometallic Fullerenes With Lewis Acids And Use As An Effective Purification Method, Steven Stevenson, Mary A. Mackey, Jane E. Pickens, Melissa A. Stuart, Bridget S. Confait, J. Paige Phillips Dec 2009

Selective Complexation And Reactivity Of Metallic Nitride And Oxometallic Fullerenes With Lewis Acids And Use As An Effective Purification Method, Steven Stevenson, Mary A. Mackey, Jane E. Pickens, Melissa A. Stuart, Bridget S. Confait, J. Paige Phillips

Faculty Publications

Metallic nitride fullerenes (MNFs) and oxometallic fullerenes (OMFs) react quickly with an array of Lewis acids. Empty-cage fullerenes are largely unreactive under conditions used in this study. The reactivity order is Sc4O2@Ih-C80 > Sc3N@C78 > Sc3N@C68 > Sc3N@D5h-C80 > Sc3N@Ih-C80. Manipulations of Lewis acids, molar ratios, and kinetic differences within the family of OMF and MNF metallofullerenes are demonstrated in a selective precipitation scheme, which can be used either alone for purifying Sc3N@Ih …


Solid State And Solution Dynamics Of Pyridine Based Tetraaza- Macrocyclic Lanthanide Chelates Possessing Phosphonate Ligating Functionality (Ln-Pctmb): Effect On Relaxometry And Optical Properties, Garry Kiefer, Mark Woods Dec 2009

Solid State And Solution Dynamics Of Pyridine Based Tetraaza- Macrocyclic Lanthanide Chelates Possessing Phosphonate Ligating Functionality (Ln-Pctmb): Effect On Relaxometry And Optical Properties, Garry Kiefer, Mark Woods

Chemistry Faculty Publications and Presentations

The macrocyclic ligand 3,6,9-tris(methylenebutyl phosphonic acid)-3,6,9−15-tetraazabicyclo [9.3.1]pentadeca-1(15),11,13-triene (PCTMB) was synthesized and complexes of Eu3+, Tb3+, and Gd3+ studied by X-ray crystallography, luminescence, and relaxometry. In the crystal these complexes are dimeric and possess 8-coordinate Ln3+ centers that are linked by bridging phosphonates. The rigidity introduced by the pyridyl nucleus forces the EuPCTMB and TbPCTMB to adopt a twisted snub disphenoid (TSD) coordination geometry. Examination of the 5D07F0 luminescent transition of EuPCTMB in the solid state confirmed the existence of a single distinct Eu3+ coordination environment, whereas two …


Rfx2 Is A Candidate Downstream Amplifier Of A-Myb Regulation In Mouse Spermatogenesis, Gary C. Horvath, Malathi K. Kistler, Wilson Stephen Kistler Dec 2009

Rfx2 Is A Candidate Downstream Amplifier Of A-Myb Regulation In Mouse Spermatogenesis, Gary C. Horvath, Malathi K. Kistler, Wilson Stephen Kistler

Faculty Publications

Background: Mammalian spermatogenesis involves formation of haploid cells from the male germline and then a complex morphological transformation to generate motile sperm. Focusing on meiotic prophase, some tissue-specific transcription factors are known (A-MYB) or suspected (RFX2) to play important roles in modulating gene expression in pachytene spermatocytes. The current work was initiated to identify both downstream and upstream regulatory connections for Rfx2.

Results: Searches of pachytene up-regulated genes identified high affinity RFX binding sites (X boxes) in promoter regions of several new genes: Adam5, Pdcl2, and Spag6. We confirmed a strong promoter-region X-box for Alf, a germ cell-specific variant of …


Carbamothioates In The Synthesis Of Diaroyl Sulfides; Selectivity In The Addition Of Diaroyl Sulfides To Acetylenic And Ethylenic Π−Deficient Compounds, Ashraf A. Aly, Alan B. Brown, Alaa A. Hasaan, Kamal M. El-Shaieb, Tarek M. Bedair Dec 2009

Carbamothioates In The Synthesis Of Diaroyl Sulfides; Selectivity In The Addition Of Diaroyl Sulfides To Acetylenic And Ethylenic Π−Deficient Compounds, Ashraf A. Aly, Alan B. Brown, Alaa A. Hasaan, Kamal M. El-Shaieb, Tarek M. Bedair

Chemistry and Chemical Engineering Faculty Publications

Diaroyl sulfides were prepared in one-pot reaction from ethylenediamine and carbon disulfide, via reaction of in situ generated ethylene-bis- carbamodithioates with aroyl chlorides. The reaction of diaroyl sulfides with acetylenic and ethylenic π-deficient compounds such as dimethyl acetylenedicarboxylate, ethyl propiolate, (E)-1,4-diphenylbut-2-ene-1,4-dione and 1,4-diphenylbut-2-yne-1,4-dione afforded the corresponding thionylated products. NMR spectroscopic data of the isolated products were discussed. © ARKAT USA, Inc.


Isolation And X-Ray Structural Characterization Of A Dicationic Homotrimer Of 2,3,6,7-Tetramethoxy-9,10-Dimethylanthracene Cation Radical, Matthew J. Modjewski, Ruchi Shukla, Sergey Lindeman, Rajendra Rathore Dec 2009

Isolation And X-Ray Structural Characterization Of A Dicationic Homotrimer Of 2,3,6,7-Tetramethoxy-9,10-Dimethylanthracene Cation Radical, Matthew J. Modjewski, Ruchi Shukla, Sergey Lindeman, Rajendra Rathore

Chemistry Faculty Research and Publications

Electrochemical oxidation of 2,3,6,7-tetramethoxy-9,10-dimethylanthracene (1) showed that it undergoes a highly reversible electrochemical oxidation (Eox = 0.81 V vs SCE) and forms a modestly stable cation-radical salt in solution. X-ray crystallography established that 1+SbCl6- crystallizes as a (centrosymmetric) dicationic homotrimer via a close cofacial association of a pair of cationic and one neutral molecule of 1 with an interplanar separation of ∼3.2 Å. The structure of the dicationic homotrimer was also reproduced by DFT calculations. Furthermore, the structure of a dicationic spiro adduct, formed by a slow decomposition of a solution of 1+ …


Expression Artifact With Retroviral Vectors Based On Pbmn, Yoshitaka Fukunaga, Robert A. Svoboda, Ronald Cerny, Keith R. Johnson, Margaret J. Wheelock Dec 2009

Expression Artifact With Retroviral Vectors Based On Pbmn, Yoshitaka Fukunaga, Robert A. Svoboda, Ronald Cerny, Keith R. Johnson, Margaret J. Wheelock

Ronald Cerny Publications

While characterizing various splice forms of p120 catenin, we observed what appeared to be a novel posttranslational modification of p120, resulting in a higher molecular weight form that was dependent on the splicing pattern. Further investigation revealed the higher molecular weight form to be a fusion protein between sequences encoded by the retroviral vector and p120. We found that the publicly available sequence of the vector we used does not agree with the experimental sequence. We caution other investigators to be aware of this potential artifact.


2,5-Dichlorothiophene 1,1-Dioxide, Jonathan B. Briggs, Wenling Jia, Mikael D. Jazdzyk, Glen P. Miller Dec 2009

2,5-Dichlorothiophene 1,1-Dioxide, Jonathan B. Briggs, Wenling Jia, Mikael D. Jazdzyk, Glen P. Miller

Chemistry

The complete molecule of the title compound, C(4)H(2)Cl(2)O(2)S, is generated by crystallographic twofold symmetry, with the S atom lying on the rotation axis. In the crystal, the molecules are linked by C-H center dot center dot center dot O hydrogen bonds..


The Ecology Of The Peaks Of Otter Salamander (Plethodon Hubrichti) In Sympatry With The Eastern Red-Backed Salamander (Plethodon Cinereus), Norman Reichenbach, Andrew Kniowski Dec 2009

The Ecology Of The Peaks Of Otter Salamander (Plethodon Hubrichti) In Sympatry With The Eastern Red-Backed Salamander (Plethodon Cinereus), Norman Reichenbach, Andrew Kniowski

Faculty Publications and Presentations

The Peaks of Otter Salamander, Plethodon hubrichti, is found along a 19 km length of the Blue Ridge Mountains, Virginia, USA, often in sympatry with the Eastern Red-backed Salamander, P. cinereus. In a sympatric area of Bedford County, Virginia, we conducted a mark-recapture study on a 10 × 10 m site. Surface densities of salamanders increased as the number of days without precipitation prior to a collection event increased. This suggests vertical movements in response to surface moisture. When salamanders returned to the surface after rain, individuals appeared to “shuffle” between rocks and likely, leaf litter. That is, we were …


Reactivity Of Phenyldi(2-Thienyl)Phosphine Towards Group 7 Metal Carbonyls: Carbon–Phosphorus Bond Activation, Shishir Ghosh, Alok K. Das, Noorjahan Begum, Daniel T. Haworth, Sergey Lindeman, James R. Gardinier, Tasneem A. Siddiquee, Dennis W. Bennett, Ebbe Nordlander, Graeme Hogarth, Shariff E. Kabir Dec 2009

Reactivity Of Phenyldi(2-Thienyl)Phosphine Towards Group 7 Metal Carbonyls: Carbon–Phosphorus Bond Activation, Shishir Ghosh, Alok K. Das, Noorjahan Begum, Daniel T. Haworth, Sergey Lindeman, James R. Gardinier, Tasneem A. Siddiquee, Dennis W. Bennett, Ebbe Nordlander, Graeme Hogarth, Shariff E. Kabir

Chemistry Faculty Research and Publications

Addition of phenyldi(2-thienyl)phosphine (PPhTh2) to [Re2(CO)10−n(NCMe)n] (n = 1, 2) affords the substitution products [Re2(CO)10−n(PhPTh2)n] (1, 2) together with small amounts of fac-[ClRe(CO)3(PPhTh2)2] (3) (n = 2). Reaction of [Re2(CO)10] with PPhTh2in refluxing xylene affords a mixture which includes 2, [Re2(CO)7(PPhTh2)(μ-PPhTh)(μ-H)] (4), [Re2(CO)7(PPhTh2)(μ-PPhTh)(μ-η11(S)-C4H3S)] (5) and …


Lead Optimization Of Cox-2 Inhibitor Nimesulide Analogs To Overcome Aromatase Inhibitor Resistance In Breast Cancer Cells, Bin Su, Shiuan Chen Dec 2009

Lead Optimization Of Cox-2 Inhibitor Nimesulide Analogs To Overcome Aromatase Inhibitor Resistance In Breast Cancer Cells, Bin Su, Shiuan Chen

Chemistry Faculty Publications

A series of COX-2 selective inhibitor nimesulide derivatives were synthesized. Their anti-cell proliferation activities were evaluated with a long-term estrogen deprived MCF-7aro (LTEDaro) breast cancer cell line, which is the biological model of aromatase inhibitor resistance for hormone-dependent breast cancer. Compared to nimesulide which inhibited LTEDaro cell proliferation with an IC50 at 170.30 μM, several new compounds showed IC50 close to 1.0 μM.


Synthesis And Cytotoxic Analysis Of Some Disodium 3Β,6Β-Dihydroxysterol Disulfates, Jianguo Cui, Hui Wang, Yi Xin, Aimin Zhou Dec 2009

Synthesis And Cytotoxic Analysis Of Some Disodium 3Β,6Β-Dihydroxysterol Disulfates, Jianguo Cui, Hui Wang, Yi Xin, Aimin Zhou

Chemistry Faculty Publications

Disodium 3β,6β-dihydroxy-5α-cholestane disulfate (1) was synthesized in 4 steps with a high overall yield from cholesterol. First, cholesterol (4a) was converted to cholest-4-en-3,6-dione (5a) via oxidation with pyridinium chlorochromate (PCC) and then 5a was reduced by NaBH4 in the presence of NiCl2 to produce cholest-3β,6β-diol (6a). The reaction of 6a with the triethylamine-sulfur trioxide complex generated diammonium 3β,6β-dihydroxy-5α-cholestane disulfate (7a) and the treatment of 7a by cation exchange resin 732 (sodium form)(Na+) yielded the target steroid 1. Disodium 24-ethyl-3β,6β-dihydroxycholest-22-ene disulfate (2) and disodium 24-ethyl-3β,6β-dihydroxycholestane disulfate (3) were synthesized using a similar method. The cytotoxicity of these compounds against Sk-Hep-1 (human …


Modeling The Fluorescence Of Protein-Embedded Tryptophans With Ab Initio Multiconfigurational Quantum Chemistry: The Limiting Cases Of Parvalbumin And Monellin, Sara Pistolesi, Adalgisa Sinicropi, Rebecca Pogni, Riccardo Basosi, Nicolas Ferre, Massimo Olivucci Dec 2009

Modeling The Fluorescence Of Protein-Embedded Tryptophans With Ab Initio Multiconfigurational Quantum Chemistry: The Limiting Cases Of Parvalbumin And Monellin, Sara Pistolesi, Adalgisa Sinicropi, Rebecca Pogni, Riccardo Basosi, Nicolas Ferre, Massimo Olivucci

Chemistry Faculty Publications

We show that a quantum-mechanics/molecular-mechanics strategy based on ab initio (i.e., first principle) multiconfigurational perturbation theory can reproduce the spectral properties of a tryptophan residue embedded in the contrasting hydrophobic and hydrophilic environments of parvalbumin and monellin, respectively. We show that the observed absorption and emission energies can be reproduced with a less than 3 kcal mol(-1) error. The analysis of the computed emission energies based on a protein disassembly scheme and protein electrostatic potential mapping allows for a detailed understanding of the factors modulating the tryptophan emission. It is shown that for rnonellin, where the tryptophan is exposed to …


Thermochromic Absorption And Photoluminescence In [Pt(Ppy)(Mu-Ph(2)Pz)](2), Aaron A. Rachford, Felix N. Castellano Dec 2009

Thermochromic Absorption And Photoluminescence In [Pt(Ppy)(Mu-Ph(2)Pz)](2), Aaron A. Rachford, Felix N. Castellano

Chemistry Faculty Publications

The temperature effects on the spectral properties and photophysics of a new d(8)-d(8) dinuclear Pt-II chromophore, [Pt(ppy)(mu-Ph(2)pz)](2) (ppy is 2-phenylpyridine and Ph(2)pz is 3,5-diphenylpyrazolate), have been investigated. The thermochromic shifts are tentatively ascribed to intramolecular sigma interactions between the two pseudocofacial d(Z2) orbitals. Substantial emission profile changes occur in the solid state, solution, and doped polymer films.


Stimuli-Responsive Hydrogel Microdomes Integrated With Genetically Engineered Proteins For High-Throughput Screening Of Pharmaceuticals, Sylvia Daunert, Sapna K. Deo, Jason Douglas Ehrick, Tyler William Browning, Leonidas G. Bachas Dec 2009

Stimuli-Responsive Hydrogel Microdomes Integrated With Genetically Engineered Proteins For High-Throughput Screening Of Pharmaceuticals, Sylvia Daunert, Sapna K. Deo, Jason Douglas Ehrick, Tyler William Browning, Leonidas G. Bachas

Chemistry Faculty Patents

A hydrogel microdome that can swell in response to a stimuli or target molecule is formed by polymerizing a mixture comprising a monomer capable of forming a hydrogel with a biopolymer. An array of hydrogel microdomes can be formed on a substrate by microspotting the mixture and polymerizing. The array can be used for high-throughput screening of analytes as well as for use as an actuator and biosensor using the swelling property of the hydrogel.


Chemistry Of Zirconia And Its Bioanalytical Applications, Oge Anazia Dec 2009

Chemistry Of Zirconia And Its Bioanalytical Applications, Oge Anazia

Masters Theses & Specialist Projects

This research studies the chemical nature of zirconia and the complex surface chemistry of zirconia in order to better comprehend its behavior under chromatographic conditions. This research shows how the physical and chemical properties of zirconia depend strongly on the thermal treatment during synthesis. The morphology of the samples was also studied. The absorption capability of Adenosine Triphosphate (ATP) on zirconia was also monitored and spectrally characterized.

The results of this research showed how the properties of zirconia vary with thermal treatment. It was observed that the zirconia prepared at a higher temperature had lower surface area, lower pore size …


A Characterization Of Caffeine Imprinted Polypyrrole Electrode, Deepika Mandadi Dec 2009

A Characterization Of Caffeine Imprinted Polypyrrole Electrode, Deepika Mandadi

Masters Theses & Specialist Projects

Nanotechnology holds great potential for improving our lives by creating many new materials and devices in medical sciences, electronics and also in energy production. Molecularly imprinted polymers (MIPs) are highly stable synthetic polymers that possess molecular recognition properties due to cavities created in the polymer matrix that are complementary to an analyte both in shape and in positioning of functional groups. These MIPs have been widely employed for diverse applications (e.g., in chromatographic separation, drug screening, chemosensors, catalysis, immunoassays etc) due to their specificity towards the target molecules and high stability against physicochemical perturbations. Conductive polymers, (CPs) such as polypyrrole, …


Kinetic Studies Of The Sulfoxidation Of Aryl Methyl Sulfides By Trans-Dioxoruthenium(Vi) Porphyrin Complexes, Chris Abebrese Dec 2009

Kinetic Studies Of The Sulfoxidation Of Aryl Methyl Sulfides By Trans-Dioxoruthenium(Vi) Porphyrin Complexes, Chris Abebrese

Masters Theses & Specialist Projects

The development of an efficient, catalytically active, biomimetic model for cytochrome P-450 enzymes has been an area of intense research activity. Ruthenium porphyrin complexes have been the center of this research and have successfully been utilized, as catalysts, in major oxidation reactions such as the hydroxylation of alkanes, the epoxidation of alkenes and aromatic rings, and the N-oxidation of amines, among others. In this project, the kinetics of two-electron sulfoxidation of para-substituted phenyl methyl sulfides to the corresponding sulfoxides with well-characterized trans-dioxoruthenium(VI) porphyrin complexes were studied by rapid stopped-flow spectroscopy. The substituent effect in sulfides and in dioxoruthenium(VI) complexes were …


Copper(I) Complexes Of Heterocyclic Thiourea Ligands, Aakarsh Saxena, Emily C. Dugan, Jeffrey Liaw, Matthew D. Dembo, Robert D. Pike Dec 2009

Copper(I) Complexes Of Heterocyclic Thiourea Ligands, Aakarsh Saxena, Emily C. Dugan, Jeffrey Liaw, Matthew D. Dembo, Robert D. Pike

Arts & Sciences Articles

The coordination of heterocyclic thiourea ligands (L = N-(2-pyridyl)-N′-phenylthiourea (1), N-(2-pyridyl)-N′-methylthiourea (2), N-(3-pyridyl)-N′-phenylthiourea (3), N-(3-pyridyl)-N′-methylthiourea (4), N-(4-pyridyl)-N′-phenylthiourea (5), N-(2-pyrimidyl)-N′-phenylthiourea (6), N-(2-pyrimidyl)-N′-methylthiourea (7), N-(2-thiazolyl)-N′-methylthiourea (8), N-(2-benzothiazolyl)-N′-methylthiourea (9), N,N′-bis(2-pyridyl)thiourea (10) and N,N′-bis(3-pyridyl)thiourea (11)) with CuX (X = Cl, Br, I, NO3) has been investigated. CuX:L product stoichiometries of 1:1–1:5 were found, with 1:1 being most common. X-ray structures of four 3-coordinate mononuclear CuXL2 complexes (CuCl(6)2, CuCl(7)2, CuBr(6)2, and CuBr(9)2) …


Off-Metal Synthesis Of Some Aryl Substituted Rhenium N5-Cyclopenta [C] Pyridazyl Complexes, James Leif Neathery Dec 2009

Off-Metal Synthesis Of Some Aryl Substituted Rhenium N5-Cyclopenta [C] Pyridazyl Complexes, James Leif Neathery

Masters Theses & Specialist Projects

Heterocyclic organic and organometallic compounds (e.g. polypyrrole), and their derivatives, have been of great interest for conductive polymers due to their novel properties and environmental stability as compared to non-aromatic analogs (e.g. polyacetylene). Our current interests focus upon the potential role of pyridazines in next generation electronic devices that utilize organics as the semiconducting material. Pyridazines, 6-membered aromatic rings with two adjacent nitrogens, are promising candidates for a variety of materials and commercial applications. These molecular electronic materials posses several advantages over traditional inorganic semiconducting materials including lower cost of production, higher processibility, and the ability to function on flexible …


Subcutaneous Administration Of Tc007 Reduces Disease Severity In An Animal Model Of Sma, Virginia B. Mattis, Marina Y. Fosso, Cheng-Wei Tom Chang, Christian L. Lorson Nov 2009

Subcutaneous Administration Of Tc007 Reduces Disease Severity In An Animal Model Of Sma, Virginia B. Mattis, Marina Y. Fosso, Cheng-Wei Tom Chang, Christian L. Lorson

Chemistry and Biochemistry Faculty Publications

Background Spinal Muscular Atrophy (SMA) is the leading genetic cause of infantile death. It is caused by the loss of functional Survival Motor Neuron 1 (SMN1). There is a nearly identical copy gene, SMN2, but it is unable to rescue from disease due to an alternative splicing event that excises a necessary exon (exon 7) from the majority of SMN2-derived transcripts. While SMNΔ7 protein has severely reduced functionality, the exon 7 sequences may not be specifically required for all activities. Therefore, aminoglycoside antibiotics previously shown to suppress stop codon recognition and promote translation read-through have been examined to increase the …


Sensors: A Novel Lateral Field Excited Acoustic Wave Sensor For Chemical And Biological Agents, John F. Vetelino, David Frankel, Carl Tripp, Paul J. Millard Nov 2009

Sensors: A Novel Lateral Field Excited Acoustic Wave Sensor For Chemical And Biological Agents, John F. Vetelino, David Frankel, Carl Tripp, Paul J. Millard

University of Maine Office of Research Administration: Grant Reports

Sensors for the sensitive and selective detection of chemical agents and a biological agent are being developed. The sensor structure consists of a piezoelectric platform that is coated with a film that selectively sorbs a chemical or biological agent of interest. The sensitivity of the sensor is embodied in the sensor platform, which consists of a quartz crystal that is excited by a lateral electric field. The exciting electrodes are placed opposite to the sensing surface, and the sensing film is attached directly to the sensor platform. This arrangement is in contrast to the standard quartz microbalance (QCM), where the …


Increased Yields And Simplified Purification With A Second-Generation Cobalt Catalyst For The Oxidative Formation Of Trans-Thf Rings., Cory Palmer, Nicholas A Morra, Andrew C Stevens, Barbora Bajtos, Ben P Machin, Brian L Pagenkopf Nov 2009

Increased Yields And Simplified Purification With A Second-Generation Cobalt Catalyst For The Oxidative Formation Of Trans-Thf Rings., Cory Palmer, Nicholas A Morra, Andrew C Stevens, Barbora Bajtos, Ben P Machin, Brian L Pagenkopf

Chemistry Publications

The synthesis of a second-generation cobalt catalyst for the formation of trans-THF products via the Mukaiyama aerobic oxidative cyclization is reported. Two procedures have been developed with the new water-soluble catalyst that give superior yields and greatly simplify purification compared to the previous catalysts.


Determination Of 6-Benzylthioinosine In Mouse And Human Plasma By Liquid Chromatography–Tandem Mass Spectrometry, Lan Li, Yan Xu, David N. Wald, William Tse Nov 2009

Determination Of 6-Benzylthioinosine In Mouse And Human Plasma By Liquid Chromatography–Tandem Mass Spectrometry, Lan Li, Yan Xu, David N. Wald, William Tse

Chemistry Faculty Publications

This paper described the development and validation of a liquid chromatography–tandem mass spectrometry (LC–MS/MS) method for the quantitative determination of 6-benzylthioinosine (6BT), a novel myeloid leukemia differentiation-inducing agent, in mouse and human plasma. In this method, 2-amino-6-benzylthioinosine (2A6BT) was used as internal standard and ethyl acetate was used as organic solvent for the extraction of 6BT and internal standard from plasma samples. The extracted samples were separated on YMC ODS-AQ® column (2.0 mm × 50 mm), and the eluates from the column were monitored by the positive-electrospray-ionization tandem mass spectrometer (ESI+-MS/MS). Quantification of 6BT by internal calibration with 2A6BT was …


Inhibitors Of Bacterial N-Succinyl-L,L-Diaminopimelic Acid Desuccinylase (Dape) And Demonstration Of In Vitro Antimicrobial Activity, Danuta Gillner, Nicola Armoush, Richard C. Holz, Daniel P. Becker Nov 2009

Inhibitors Of Bacterial N-Succinyl-L,L-Diaminopimelic Acid Desuccinylase (Dape) And Demonstration Of In Vitro Antimicrobial Activity, Danuta Gillner, Nicola Armoush, Richard C. Holz, Daniel P. Becker

Chemistry Faculty Research and Publications

The dapE-encoded N-succinyl-L,L-diaminopimelic acid desuccinylase (DapE) is a critical bacterial enzyme for the construction of the bacterial cell wall. A screen biased toward compounds containing zinc-binding groups (ZBG’s) including thiols, carboxylic acids, boronic acids, phosphonates and hydroxamates has delivered a number of micromolar inhibitors of DapE from Haemophilus influenzae, including the low micromolar inhibitor L-captopril (IC50 = 3.3 μM, Ki = 1.8 μM). In vitro antimicrobial activity was demonstrated for l-captopril against Escherichia coli.


Inhibitors Of Bacterial N-Succinyl-L,L-Diaminopimelic Acid Desuccinylase (Dape) And Demonstration Of In Vitro Antimicrobial Activity, Danuta Gillner, Nicola Armoush, Richard C. Holz, Daniel P. Becker Nov 2009

Inhibitors Of Bacterial N-Succinyl-L,L-Diaminopimelic Acid Desuccinylase (Dape) And Demonstration Of In Vitro Antimicrobial Activity, Danuta Gillner, Nicola Armoush, Richard C. Holz, Daniel P. Becker

Chemistry: Faculty Publications and Other Works

The dapE-encoded N-succinyl-l,l-diaminopimelic acid desuccinylase (DapE) is a critical bacterial enzyme for the construction of the bacterial cell wall. A screen biased toward compounds containing zinc-binding groups (ZBG’s) including thiols, carboxylic acids, boronic acids, phosphonates and hydroxamates has delivered a number of micromolar inhibitors of DapE from Haemophilus influenzae, including the low micromolar inhibitor l-captopril (IC50 = 3.3 μM, Ki = 1.8 μM). In vitro antimicrobial activity was demonstrated for l-captopril against Escherichia coli.


Electrochemical And Photovoltaic Properties Of Electropolymerized Poly(Thienyl-Silole)S, Joshua C. Byers, Paul M. Dicarmine, Mahmoud M. A. R. Moustafa, Xin Wang, Brian Pagenkopf, Oleg A. Semenikhin Nov 2009

Electrochemical And Photovoltaic Properties Of Electropolymerized Poly(Thienyl-Silole)S, Joshua C. Byers, Paul M. Dicarmine, Mahmoud M. A. R. Moustafa, Xin Wang, Brian Pagenkopf, Oleg A. Semenikhin

Chemistry Publications

Electrochemical and photoelectrochemical properties were studied of a series of donor−acceptor materials based on polythiophene modified with silole moieties. The materials were prepared by electrochemical anodic polymerization of 2,5-bis([2,2′-bithiophen]-5-yl)-1,1-dimethyl-3,4-diphenylsilole and 2,5-bis([2,2′-terthiophen]-5-yl)-1,1-dimethyl-3,4-diphenylsilole, as well as copolymerization of these monomers with 2,2′-bithiophene. Photocurrent measurements showed that introduction of silole resulted in a considerable enhancement of the photovoltaic properties of silole-containing materials and especially the fill factor. However, as demonstrated by Mott−Schottky measurements, electropolymerized silole-containing materials showed a substantial degree of disorder and high density of states in the midgap, which negatively affected their photovoltaic properties. Atomic force microscopy (AFM) and phase imaging …