Presentation Abstracts

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In vitro and in vivo investigation of matrix metalloproteinase expression in metastatic tumor models

Larissa Gribat

The spread of cancer may occur through the lymph nodes causing early death.  During malignancy, an overexpression of matrix metalloproteinases(MMPs) occurs through which early detection could lead to more accurate prognosis.  A peptide, CCT (CTTHWGFTLC) is a possible inhibitor of MMP-2 and MMP-9 to determine the location of cancer growth.  CCT is conjugated with DOTA (1,4,7,10-tetraazacyclotetradecane-N’,N’’,N’’’,N’’’’-tetraacetic acid)  and ⁶⁴Cu.  Both in vivo and in vitro inhibition is measured.  Positron emission tomography (PET) can identify Cu(2)-DOTA-CCT for imaging with tumor gelatinase targeting while in vitro affinity is determined with a fluorogenic substrate assay. Cu(2)-DOTA-CCT inhibited hMMP-2 and mMMP-9 in vitro.  For both B16F10 and MDA-MB-435 tumors in vivo, Cu(2)-DOTA-CCT was taken up inconsistently with microPET and zymography.  Thus, Cu(2)-DOTA-CCT is not selective enough for inhibition of MMP-2 and MMP-9 for cancer spread diagnosis.  The unspecific uptake of Cu(2)-DOTA-CCT is due to instability in blood for protein-bound radioactivity. (Anderson, C.J. In vitro and in vivo investigation of matrix metalloproteinase expression in metastatic tumor models. Nucl Med Biol. 2006, 33, 227-237).

 

Polystyrene Aerogels with β, γ, and ε Crystalline Phases

Joe Siegel

The effects of thermal treatment and supercritical carbon dioxide extraction procedures on the crystal structure of sPS gels are observed by wide-angle X-ray diffraction and electron microscopy.   Supercritical carbon dioxide extraction treatment is used to create the δ, β, and γ crystalline phases.  These phases are found to have a high porosity with a fibrillar morphology.  Also the ε crystalline phase was obtained by treating the γ-form with liquid chloroform followed by chloroform removal by volatile guests of sPS aerogels.  Measurements of the sorption of organic molecules from diluted aqueous solutions, with different crystalline phases, indicate that the ε-form is best suited for the detection and removal of long organic pollutants.

 

Food-Miles and the Relative Climate Impacts of Food Choices in the United States

Philip Denight

In the world today carbon emissions and greenhouse gases play an enormous role in how we interact with the environment. In the United States, very few studies have compared the life-cycle of greenhouse gas to the food production cycle. Through the input-output life cycle assessment these figures can be determined and utilized to figure out how to decrease the carbon-footprint. Several variety of food sources (red meat, dairy products, cereals, etc) and methods of transportation (water, truck, rail) were recorded for carbon output. It was found that trucking is responsible for a majority (71%) of transport related greenhouse gases and red meat and cereals equally share the carbon-footprint (2300 ton-km/household-yr) for food sources. It is recommended that dietary shift can be an effective means of lowering greenhouse gases by switching to chicken, eggs, fish or vegetables and away from red meats and cereals.

Article: http://pubs.acs.org/doi/abs/10.1021/es702969f?prevSearch=Food-miles%2Band%2Bthe%2Brelative%2Bclimate%2Bimpacts%2Bof%2Bfood%2Bchoices&searchHistoryKey=

 

 

Medicinal Applications of Animal Toxins

Avash Shrestha

Animal toxin is one of the most useful biochemical substances that exist in nature, consisting of specific peptides, proteins, and organic and inorganic molecules/ions. These chemicals have the potential to deliver their contents to specific locations within an animal’s body for specific functions, usually very lethal. The ability of animal toxins to be location specific in its actions makes it fascinating for the study of its medicinal characteristics based on its potency and effects on the human body. Specific animal toxins such as bees, snakes and scorpions venom have shown that they can be used in treating diseases like Alzheimer’s disease, cardiovascular diseases muscular disorders .

Armugam, A., and K. Jeyaseelan. “Snake venom components and their applications in biomedicine.”  Cellular and Molecular Life Sciences 13 Nov. 2006

 

 

Time-Resolved pH/pO₂ Mapping with Luminescent Hybrid Sensors

Laura Tvedte

A method for simultaneous detection of two or more parameters (in this case, pH and pO₂) using absorbent or luminescent dyes as indicators is described. This method involves detection of the pH signal as a hybrid signal (dependent on pH and pO₂) along with detection of the pO₂ signal as a pure (non-hybrid) signal. This method affords an advantage in determining parameters in systems where changes are based on two or more parameters. The hybrid pH sensor successfully measures a range of pH 7.6-pH 8.7 with a maximum deviation of pH 0.03. The pO₂ sensor measures a range of 0-200 hPa pO₂ with a maximum deviation of 6.5 hPa pO₂. PH/pO2 example images obtained in marine sediment are taken using this method and presented.

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Chemical Mechanisms for Skin Sensitization by Aromatic Compounds with Hydroxy and Amino Groups

Jeff Boschen

Skin sensitization is observed in aromatic diamino-, dihydroxy-, and amino-hydroxy compounds. As a result of a recent animal testing ban on chemicals used for cosmetics in the European Union, new methods are needed for predicting skin sensitization potency. One potential method is analysis of reaction methods. In this study, the potency and cross-reactivity data from published animal tests is used to make mechanistic predictions. For para and ortho substituted compounds, two reaction mechanisms are suggested: oxidation to electrophilic quinones or quinone imines, or formation of free radicals such as the Wurster salt. For meta compounds neither of these mechanisms are favored, instead a different molecular mechanism is proposed. Using quantum mechanics calculations, this mechanism can be used to explain potency data for meta substituted structures.

Bibliography

Aptula, A. O., Enoch, S.J., Roberts, D. W.  Chem. Res. Toxicol. 2009 22 (9), 1541-1547

Roberts, D. W. and Aptula, A. O.  J. Appl. Toxicol. 2007 28, 377– 387

Aptula, A. O. and Roberts, D. W.  Chem. Res. Toxicol. 2006 19, 1097– 1105

 

Primary and Secondary Phosphine Complexes of Iron Porphyrins and Ruthenium Phthalocyanine: Synthesis, Structure, and P–H Bond Functionalization

Jeff Hon

Interactions of hemoproteins are widely studied for their implications in humans and medicine. Specifically, the binding mechanism of hemoproteins and various drugs are of concern and provide insight into new drug synthesis. Phthalocyanine complexes serve as a useful analog to hemoglobin and are used to study binding interactions, specifically phosphine substrates. The reduction of ruthenium(II) phthalocyanine have generated several primary and secondary phosphines of interest. Furthermore, the P-H  bond has been functionalized and provide further interest into phosphine complexes.

 

Bibliography

1. Huang, J et al. Inorg. Chem., 2008, 47 (20), pp 9166–9181

2. Dahlen, M.A. Ind. Eng. Chem., 1939, 31 (7), pp 839–847

3. Wink, D and Ford, P.C. Excited States and Reactive Intermediates, Chapter 14, 1986, pp 197-211 ACS Symposium Series, Volume 307.

 

 

Analysis of Ecologically Relevant Pharmaceuticals in Wastewater and Surface Water Using Selective Solid-Phase Extraction and UPLC—MS/MS

Kevin Schmitt
CHEM 345:  Junior Chemistry Seminar

Increasing production and variety of active pharmaceutical ingredients (APIs) and metabolites used in human and veterinary medicine leads to the release of greater quantities of these materials into the environment.  The presence of these compounds or their derivatives in increasing concentrations in wastewater and surface water provides opportunities for undesirable ecological effects to occur.  A new method for the analysis of 6 metabolites and 48 API’s in water samples is presented.  The target analytes are selected with regard to their predicted environmental impact, and the method utilizes the techniques of selective solid-phase extraction and ultraperformance liquid chromatography with triple quadrupole mass spectrometry.  Four separate chromatographic runs are used to determine the presence and concentration of analytes in the following groups:  basic APIs 1 (antidepressants, antibiotics), basic APIs 2 (cardiovascular drugs, pain medications), neutral APIs, and acidic APIs.  The total time required for analysis of all 54 compounds is 48 minutes, and the method limits of detection range from 1.0 to 51 ng/L.  Analysis of wastewater and surface water samples resulted in the detection of 38 and the quantitation of 36 of the 54 total analytes.

Bibliography

(1) Kostich, M.S.; Lazorchak, J.M.; Batt, A.L. Anal. Chem. 2008, 80, 5021-5030.

(2) Swartz, M.E. Separation Science Redefined [Online] 2005, May, 8-14. http://chromatographyonline.findanalytichem.com/lcgc/data/articlestandard//lcgc/242005/164646/article.pdf (accessed Oct 7, 2005).

(3) Richardson, S.D. Anal. Chem. 2008, 80, 4379-4384.

 

Kinetic Study of the Phthalimide N-Oxyl (PINO) Radical in Acetic Acid

Adam Kell

A common method of alcohol oxidation is to use a nitroxyl-radical-catalyzed reaction. These are not complete oxidations however, since nitroxyl radicals are selective oxidants. The discovery of the catalytic reactivity of N-hydroxyphthalimide (NHPI) has shown the phthalimide N-oxyl (PINO) radical to be a good candidate for oxidizing hydrocarbons. Reactions of PINO with hydrocarbons are slightly exothermic or thermoneutral. The bond dissociation energy (BDE) of the O-H of NHPI gives the same conclusion. A difference in the kinetic isotope effect (KIE) between PINO and the dimbromide readical can be explained by the difference in their enthalpies for reactions with the same hydrocarbons.

 

Bibliography

Ishii, Y.; Sakaguchi, S.; Iwahama, T. Adv. Synth. Catal. 2001, 343, 393-427.

Ueda, C.; Noyama, M.; Ohmori, H.; Masui, M. Chem. Pharm. Bull.1987, 35, 1372-1377.

 

 (−)-Mutisianthol: First Total Synthesis, Absolute Configuration, and Antitumor Activity

Chris Jeffrey

Understanding the makeup of the natural world is a major part of chemistry, and one aspect of that is being able to understand the molecular structure of the naturally occurring products. Alongside that is being able to reproduce the product synthetically. One of those products is mutisianthol, found in the Mutisa genus of flowers. In previous works, synthesis of mutisianthol had successfully produced a stereo-isomer, however, the route for total synthesis was recently discovered. Furthermore, the new process has fewer steps and is more efficient. Additionally, the product was shown to have moderate anti-tumor properties with a few cells.

-Bianco, G.G.; et. al., J. Org. Chem. 2009, 74, 2561-2566

 

 Trace Analysis of Peroxide-Based Explosives

Michael Hogard

In recent years, peroxide-based explosives have been commonly been involved in drug crimes and terrorism incidents, mainly due to their relatively simple and cheap synthesis. The study develops the first method for trace analysis of two peroxide-based explosives, triacetone triperoxide (TATP) and hexamethylene triperoxide diamine (HMTD). A reversed-phase high-performance liquid chromatography method with postcolumn UV irradiation and fluorescence detection is used for the analysis after the analytes have been degraded to hydrogen peroxide, which allowed for the explosives to be identified with a high degree of selectivity. The limits of detection for both TATP and HMTD were 2 × 10^-6 mol/L. This method has been used and proven effective on not only samples prepared in the laboratory, but in the analysis of real samples.

Bibliography

(1) Schulte-Ladbeck, R.; Karst, U.; Kolla, P. Trace analysis of peroxide-based explosives. Anal. Chem. 2003, 75 (4), 731-735.

(2) Schaefer, W.P.; Fourkas, J.T.; Tiemann, B.G. Structure of hexamethylene triperoxide diamine. J. Am. Chem. Soc. 1985, 107 (8), 2461-2463.

(3) Groth, P. Crystal structure of 3,3,6,6,9,9-hexamethyl-1,2,4,5,7,8-hexa-oxacyclononane (“trimeric acetone peroxide”). Acta Chem. Scand. 1969, 23 (4), 1311−1329.

 

 

Quantitative and Real-Time Detection of Secretion of Chemical Messengers from Individual Platelets

Ivan Lenov

Serotonin release is essential for normal body functions and can be measured using radiometric assays and chromatographic separations. However, those methods have very poor temporal resolution and can’t focus on a single cell. In this study, a carbon-fiber microelectrode is used to measure individual cell release of serotonin and histamine from rabbit cells with amperometry. The quantal release of serotonin was measured to be a concentration of 0.6 M with a release time of 7 ms. In addition, it was found that quantal size increased under hypotonic conditions in the cell’s environment, but no change was observed when the conditions were both hypertonic and isotonic. This approach can be implemented in future studies in fields such as pharmacology

 

 

Crystallization from Water-in-Oil Emulsions As a Route to Spherical Particulates: Glycine and the Hydrochloride Salts of Glutamic Acid and Ephedrine

Patrick Barney

 

Emulsion crystallization is a method of controlling particle properties, and is part of technique that is used to form spherical particles. In pharmaceutical industries, spherical particles are known to have advantages in terms of flow and compression properties.  This study was carried out to define possible working space for the development of emulsion crystallization of materials that could mimic pharmaceutically active compounds.  In this study three water-soluble materials, glycine, L-glutamic acid hydrochloride, and ephedrine hydrochloride from water-in-oil emulsion were explored.  In particular, work on these compounds show the significance of stirring, surfactant, and templating additive choice. It is evident that these are important in developing a practical route to utilizing this technology.  It is also seen that the relative solubility of the solute in the two liquid phases may prevent the use of the drops as crystallisation environments.  This leads to unwanted growth of large crystals in the continuous phase.

 

 

Bibliography

 

(1)   Chadwick, K.; Davey,R.J.; Mughal R. Crystallisation from water-in-oil emulsions as a route to spherical particulates: glycine and the hydrochloride salts of glutamic acid and ephedrine. Org. Process Res. Dev. 2009.

(2)   Chen, B.D.; Cilliers, J. J. L.; Daver, R. J.; Garside, J; Woodburn, E.T. J. Am. Chem. Soc. 1998, 120, 1625-1626

(3)   Berge, N. D.; Ramsburg, A. C. Oil-in-Water emulsions for encapsulated delivery of reactive iron particles. Environ. Sci. Technol., 2009, 43 (13), pp 5060–5066

 

 

Ethanol–Drug Absorption Interaction: Potential for a Significant Effect on the Plasma Pharmacokinetics of Ethanol Vulnerable Formulations

 

Brent Dresser

 

Gastric delivery of controlled release formulations of opiate drugs is controlled by a wide variety of factors. Ethanol can compromise the time-release formulation, resulting in dose dumping. This process is aggravated by formulations that are soluble in ethanol. This can be a serious health concern considering plasma increases of 16 times in vivo studies. In this study Hydromorphone was studied, in addition to other time release opiates, and it was that hydromorphone was most affected by ethanol concentrations of 20-40%. The other characteristics of the ethanol ingested have a variety of effects on the dose dumping phenomenon. Weighing the variety of factors is almost impossible in determining the individual effects of dose dumping, and thus the safety of the product is compromised.

 

Lennemas,H., Mol. Pharmaceutics, 2009, 6 (5), pp 1429–1440

 

 

A NIST Standard Reference Material (SRM) to Support the Detection of Trace Explosives

 

Chelsea Stockwell

 

Determination of trace explosives residues is a component of anticipatory detection of terrorist threats as well as forensic evaluations. A reference material was created in order to simulate residues produced from explosive handling. Nine potential materials were tested by coating with Composition C-4, TNT (2,4,6-trinitrotoluene), or HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-Tetrazocine) and the best material was deduced based on characteristics including coating efficiency, extractability with organic solvents, thermal storage stability, consistency of particle size, and calibration potential. The reference choice was determined to be oxtadecylsilane-modified silica (C₁₈) with a particle size of 20-30 μm size. The SRM (Standard Reference Material) was then concentration certified and tested by liquid chromatography with ultraviolet absorbance detection (LC/UV), and liquid chromatography with mass spectrometric methods (LC/MS).

 

Bibliography

MacCrehan, W. A.; A NIST standard reference material (SRM) to support the detection of trace explosives. J. Anal. Chem. 2009, 81, 7189-7196.

Schulte-Ladbeck, R.; Karst, U.; Kolla, P. Trace analysis of peroxide-based explosives. Anal. Chem. 2003, 75 (4), 731-735.

Verkouteren, J. R.; J. Forensic Sci. 2007, 52 (2), 335-340.

 

 

Structural Phase Transformations of Mg₃N₂ at High Pressure: Experimental and Theoretical Studies

Margaret A. Mudd

 

Magnesium nitride, Mg₃N₂, has been used as a nitriding agent and as a catalyst. The crystal structure under ambient conditions is cubic antibixbyite (anti-C-type), similar to sesquioxides. The cubic antibixbyite structure is known to undergo structural changes with respect to temperature and pressure. For sesquioxides, transitions occur from C- to B- (monocyclic) to A-type (hexagonal) with increasing pressure. By X-ray diffraction analysis at room temperate, a reversible transformation from anti-C- to anti-B-type (monocyclic) was observed beginning at 20.6 GPa and complete at 32.5 GPa. First-principle calculations were found to be in agreement with the experimental findings. A further transformation to anti-A-type at higher pressures was not experimentally found but was predicted theoretically by use of enthalpy calculations to occur at approximately 67 GPa.

 

Biboliography

 

Hao, J.; Li, Y.; Zhou, Q.; Iiu, D.; Li, M.; Li, F.; Lei, W.; Chen, X.; Ma, Y.; cui, Q.; Zou, G.; Liu, J.; li, X. Inorg. Chem. 2009, 48, 9737-9741.

 

Guo, Q.; Zhao, Y.; Jiang, C.; Mao, W. L.; Wang, A.; Zhang, A.; Wang, Z. Inorg. Chem., 2007, 46, 6164–6169.

 

Walsh, A.; Catlow, C. R.; Sokol, A. A.; Woodley, S. M. Chem. Mat., 2009, 21, pp 49624969

 

 

The Chemical Imagination at Work in Very Tight Places

Therese Gerbich

 

When subjected to extreme pressures (hundreds of GPa’s), the typical models for structure and bonding offer an incomplete understanding of the nature of matter. Such high pressures produce a variety of responses in molecules, including the exclusion of Van der Waals space, increasing coordination numbers, shrinking bond length, and even reexamining what closest packing really means.

 

Bibliography:

Grochala, W.; Hoffman, R.; Feng, J.; Ashcroft, N. W. Angew. Chem. Int. Ed. 2007, 46, 3620 – 3642

 

 

Uptake of Aromatic Arsenicals from Soil Contaminated with Diphenylarsinic Acid by Rice

Annie Froeschner, CHEM 345

 

Many chemical warfare agents used in the 20^th century contained aromatic arsenicals (AAs), which are known to leak into the environment.  The uptake of AAs in agricultural soil by rice was studied to determine which part of the plant contained the arsenicals, which metabolic pathway AAs in soil and rice follow, and which conditions rice should be grown under to reduce the uptake of AAs.  Methylphenylarsinic acid (MPAA) was detected in rice grown in contaminated soil. Dimethlyphenylarsine oxide (DMPAO) and methyldiphenylarsine oxide (MDPAO) were detected in the straw but not in the grains grown in the contaminated soil.  Phenylarsinic acid (PAA) and MPAA concentrations decreased and DMPAO concentration increased under flooded conditions, but their concentrations were found to be unchanged under upland conditions.  MPAA and diphenylarsinic acid (DPAA) were methylated in the soil, not in the plants, and dephenylated products were detected in the straw.  DMPAO and MDPAO absorbed by the shoots were retained, and MPAA and DPAA absorbed by the shoots were translocated to the grains more easily than other AAs.

 

 

Rapid Screening of Anabolic Steroids in Urine by Reactive Desorption Electrospray Ionization

Drew Garwood

 

The use of anabolic steroids in professional and collegiate sports has increased at an exponential rate. The accepted method in testing for these substances has been gas chromatography and mass spectrometry based on the great detail produced. Steps in the procedure make this a long process, for which a faster one is sought after. A faster more efficient method combines reactive desorption electrospray ionization (reactive DESI) and tandem mass spectrometry. The seven steroids being tested include a carbonyl group, which reacted with the hydroxylamine contained in the spray during the ionization process. The dehydration of the adduct and the oxime formed was observed by reactive DESI and the protonated and sodiated forms of the ionized steroid were observed with reactive DESI and DESI that didn’t include the hydroxylamine. Analysis times were only a few seconds, limits of detection for pure compounds were less than 1 ng, and dynamic ranges were typically 2 orders of magnitude. Considerable improvements in the time efficiency needed to test for steroids were displayed by using reactive DESI rather than conventional DESI.  The tandem mass spectrometry was used as conformation identification for the rapid screening process.

 

 

High Precision Quantitative Proteomics Using iTRAQ on an LTQ Orbitrap: A New Mass Spectrometric Method Combining the Benefits of All

Matt July

 

Mass spectrometry has a plethora of applications in areas other than chemistry, especially in the field of proteomics.  Various types of mass spectrometric analyzers are able to quantify and identify specific proteins in tissue samples, but the degree of accuracy and efficiency varies among the analyzers. Since proteomics has promising applications in finding treatments for diseases, determining the method of analysis that best optimizes these parameters is important.  Three methods of mass spectrometric analysis were tested: pulsed Q dissociation (PQD), higher energy C-trap dissociation (HCP), and a hybrid collisional induced dissociation (CID) – HCP.  CID-HCP identified over twice as many proteins in a complex peptide mixture.  In addition, CID-HCP was better suited in measuring small amounts of proteins than HCP alone.  Finally, the hybrid analyzer showed practical utility in the determination of protein changes in an in vivo mouse model of cardiac hypertrophy.

 

 

Bibliography

Kösher, T.; et al.  J. Proteome Res.  2009, 8, 4743-4752.

Karp, G. Cell and Molecular Biology : Concepts and Experiments; John Wiley & Sons, Inc.: Danvers, MA, 2008; pp 49-74.

Robinson, J.W.; et al.  Undergraduate Instrumental Analysis; Marcel Dekker: New York, 2005; pp 620-647.