undergraduate research symposium - the western...

2015 WNYACS Undergraduate Research Symposium

The Eighth Annual

Undergraduate Research Symposium

Sponsored by the Western New York Section

of the American Chemical Society

Saturday April 11, 2015

D'Youville College


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A Message from the Organizing Committee

Welcome to the 8th annual Undergraduate Research Symposium sponsored by the Western

New York Section of the American Chemical Society! This year’s exciting Symposium will highlight some of the stimulating research being performed by undergraduates and their mentors from several institutions throughout Western New York and the surrounding areas, including Southern Ontario.

I hope all participants will get the chance to engage one another in active discussions about the chemistry being presented. Please use this meeting as an opportunity to develop professionally by networking with scientific peers and faculty mentors in a relaxed scientific atmosphere. And of course, have fun!

Thank you to all of our student presenters and especially to our keynote speaker, Prof. Huw Davies, of Emory University. I would also like to extend my appreciation to our generous sponsors and to the members of the Organizing Committee, without whom this Symposium would not be possible. Sincerely,

Dominic L. Ventura, Ph.D. Chair, 2015 Symposium Committee

2015 Symposium Organizing Committee

Chair: Dr. Dominic L. Ventura Department of Math and Natural Sciences, D’Youville College

Dr. Timothy M. Gregg

Department of Chemistry and Biochemistry, Canisius College

Dr. Valerie A. Frerichs Department of Chemistry, University at Buffalo SUNY

Dr. Robyn Goacher

Department of Biochemistry, Chemistry and Physics, Niagara University

Dr. Greg Soja Department of Math and Natural Sciences, D’Youville College


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Special Thanks to the Sponsors of the

2015 Undergraduate Research Symposium

The American Chemical Society

D'Youville College

Kraekler Scientific, Inc.

Pearson Higher Education

Shimadzu Corporation


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Our Keynote Speaker

Huw M. L. Davies

Department of Chemistry, Emory University, Atlanta, GA

Professor Huw M. L. Davies earned a B.Sc. in Chemistry from the University College Cardiff, Wales in 1977 and a Ph.D. in Chemistry from the University of East Anglia, England in 1980. After a postdoctoral position at Princeton University, he joined the faculty at Wake Forest University. He moved to the University at Buffalo in 1995 before joining the Department of Chemistry at Emory University in 2008, where he currently holds the position of Asa Griggs Candler Professor and is the director of Graduate Studies. Huw Davies currently holds 23 patents and is currently the director of the Center for Selective C-H Functionalization. He has also been presented several awards such as the American Chemical Society Cope Scholar award in 2005, a Fellow of the Royal Society of Chemistry in 2007, a Fellow of the American Chemical Society in 2009 and most recently he was elected a fellow of the National Academy of Inventors this past December. His research interests include investigation of dirhodium complexes as catalysts to explore novel methodolgies of donor/acceptor carbenoids to accomplish reactions such as cyclopropanation, [4+3] cycloaddition, and of course, C-H functionalization. This chemistry has also been showcased in several total syntheses to yield many natural products such as Erogorgiaene, Vibsanin E and Colombiasin A.


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Schedule of Events April 11, 2015

D'Youville College Buffalo, NY

8:00 am-8:45 am Registration (D'Youville Academic Center, Room 216)

8:45 am-9:00 am Introductory Remarks: Prof. Dominic Ventura

9:00 am-10:00 am Keynote Address:

Prof. Huw M. L. Davies, Emory University

Collaborative Approach to C-H Functionalization

10:00 am-11:45 am Student Oral Presentations: Moderator Prof. Greg Soja

11:45 am-12:30 pm Lunch (College Center, Blue Lounge, 1st Floor))

12:30 pm-2:00 pm Student Poster Presentations (College Center, Blue Lounge, 1st Floor)

2:00 pm Symposium Awards and Closing remarks: Prof. Dominic Ventura

Many thanks to our generous sponsors!!


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Oral Presentations 9:00 AM - 11:45 AM (DAC 216)

Keynote Address

9:00 AM Huw M. L. Davies, Ph.D. Emory University


Student Presentations

1. 10:00 am Cassidy Benson SUNY Fredonia Characterizing Novel Solid-State Reaction Intermediates Using Advanced In

Situ X-Ray Diffraction Techniques

2. 10:15 am Jessica H. Ciesla SUNY College of Environmental Science and Forestry Progress Towards the Synthesis and in vivo Incorporation of “Click”-Ready Fatty

Acids into Poly-[(R)-3-hydroxyalkanoate] Biopolymers

3. 10:30 am J. O. Ellison The College at Brockport, SUNY Computational Study of Imidazolium Ionic Liquid Solvation

4. 10:45 am Samantha Livingston Niagara University Determining Order of Black Ballpoint Pen Ink Deposition on Paper to Identify Forgeries in

Questioned Documents Using Time-of-Flight Secondary Ion Mass Spectrometry

5. 11:00 am Kevin Sidoran St. Bonaventure University Gold(I) Complexes Featuring Ferrocenylated N-Heterocyclic Carbenes for

Anticancer Studies

6. 11:15 am Daniel Snyder D’Youville College Synthesis of Novel Glassy Liquid Crystalline Compounds from Cholesterol

Derivatives

7. 11:30 am Sara J. Stonehouse McMaster University Syntheses and Characterization of Fluoroborate Salts of Noble-Gas

Fluorocations and the [O2]+ Cation


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Abstracts


Huw M. L. Davies

Department of Chemistry, Emory University, Atlanta, GA

Traditionally, the synthesis of complex organic compounds has relied on a carefully orchestrated strategy of reactions involving modification of functional groups. This presentation will describe an alternative approach, in which the transformations will occur at C-H bonds rather than the functional groups. This changes the logic of organic synthesis and offers exciting new approaches for the synthesis of fine chemicals for materials science and drug development.

REACTIVE SITES FOR C−H FUNCTIONALIZATION

NO

O

Br

REACTIVE SITES FOR FUNCTIONAL GROUP MODIFICATION


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Talk 1

Characterizing Novel Solid-State Reaction Intermediates Using Advanced In Situ X-Ray

Diffraction Techniques

Cassidy Benson1, Jordan Cox2, Ian Walton2 and Jason B. Benedict2*

1Department of Chemistry, SUNY Fredonia, Fredonia NY 2Department of Chemistry, University at Buffalo, SUNY, Buffalo NY

In permanently porous metal-organic frameworks (MOFs) there exist continuous channels that allow for the dynamic exchange of guest molecules. X-ray diffraction (XRD) remains one of the most powerful techniques for determining the structure of crystalline MOFs at atomic resolution. This work highlights recent progress in the design and construction of a novel apparatus for monitoring the process of guest exchange in situ by XRD, with the ultimate goal of developing a molecular-level understanding of the fundamental processes occurring within these materials.


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Talk 2

Progress Towards the Synthesis and in vivo Incorporation of “Click”-Ready Fatty Acids into

Poly-[(R)-3-hydroxyalkanoate] Biopolymers

Jessica H. Ciesla, Atahualpa Pinto and Christopher T. Nomura*

Department of Chemistry, SUNY College of Environmental Science and Forestry, Syracuse, NY Poly-[(R)-3-hydroxyalkanoate] biopolymers, or PHAs, are biocompatible and biodegradable polyesters produced natively by diverse microbial strains. PHA polymers have widespread uses in applications ranging from sustainable replacements of non-biodegradable bulk-commodity plastics to biomedical materials. Development of nanoparticle drug delivery therapeutics with PHA polymers have been tested and found effective in targeted delivery of cytotoxic drugs to cancer cells. Research is limited by a lack of control over the repeating unit composition and inability to chemically modify these polymers with ease. To tackle these problems, efforts have centered in metabolically engineering heterologous microbe strains to yield rationally designed PHAs. Recently, our lab engineered E. coli LSBJ, a microbial strain able to produce PHA copolymers with controlled unit compositions from simple and accessible fatty acid feedstocks. Expanding on this technology, we have been enthusiastically exploring our strain’s flexibility to uptake and incorporate unusual/synthetic fatty acids into PHA copolymers. We envision meaningfully broadening the application spectrum of these materials via production of chemically tractable PHA biopolymers containing “click”-ready chemical functionalities. With biomedical applications in mind, in this study we demonstrate the in vivo polymerization of click-ready synthetic 10-azidodecanoic acid and take the first exploratory steps towards the synthesis and incorporation of 6-azidohexanoic acid into PHA polymers. Our synthetic routes were designed and refined to exploit the cost-effective and synthetically adaptable nature of α,ω-diols. Thus far, 6-azidohexanoic acid has been synthesized on micro scale, future work includes larger-scale synthesis and feeding experiments with E. coli LSBJ to determine monomer take up capabilities.


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Talk 3

Computational Study of Imidazolium Ionic Liquid Solvation

J. O. Ellison and M. P. Heitz*

Department of Chemistry, The College at Brockport, SUNY, Brockport, NY

Ionic liquids are of particular interest because they offer an “environmentally friendly” alternative to volatile organic hydrocarbon (VOC) solvents. One principle of green chemistry promotes the use of innocuous solvents in chemical processing. The overall goal of our research is to determine the solvation energetics of ionic liquids when dissolved in conventional solvents such as methanol (MeOH) and water. The ionic liquids used in this work are based on the 1-alkyl-3-methylimidazolium cation and chloride anion. To date, we have studied the solvation of these ionic liquids with straight chain alkyl substituents ranging in length from 2 to 10 carbons in increments of two methylene groups. The imidazolium systems were modeled computationally using Spartan14® software using the Hartree-Fock ab initio method with 3-21G basis set. Solvation was computed using continuum dielectric solvents with SM5.4 and SM8 solvent models. The optimum cation/anion separation (energy minimum) was determined by calculating the interaction energy in both vacuum and a wide range of common solvents including methanol and DMSO. The optimum separation distance for the ionic liquids studied was not found to depend on substituent chain length. Solvation energies of solvated ion pairs and solvent separated ions were computed for all solvents studied and are discussed in this work.


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Talk 4

Determining Order of Black Ballpoint Pen Ink Deposition on Paper to Identify Forgeries in Questioned Documents Using Time-of-Flight

Secondary Ion Mass Spectrometry

Samantha Livingston and Robyn E. Goacher*

Department of Biochemistry, Chemistry and Physics, Niagara University, NY

A questioned document is considered to be any written document where there is doubt in its source or authenticity. The conventional methods to identify forgeries rely on visual exams, which depend upon the judgment of an individual, or are highly dependent on the solvent system, thus a destructive investigation leading to visibly altering the surface composition over the analysis time. Developing more effective non-destructive tools to examine questioned documents is necessary, as forgeries grow more sophisticated and more challenging to identify. For this reason, preliminary studies were performed to assess the potential of time-of-flight secondary mass spectrometry (TOF-SIMS) in determining the deposition order of layered black ballpoint pen inks. Mass spectra and images of intersections of three brands of black ballpoint pens (PapermateTM Profile, BicTM Velocity and StaplesTM Motiva) were acquired through TOF-SIMS. From the spectra, the composition of the various inks could be determined. Also, through PCA image analysis, by showing only the composition of the top ink at the intersection the order of deposition of the inks could be determined when the inks were the different brands. Further analysis is to be completed on the possibility of matrix effects that questioned documents could be exposed to, such as fingerprints, sunlight exposure, coffee stains etc. Though these initial findings provide a basis for determining the order of deposition of various inks and demonstrate the potential for a non-destructive technique to identify forgeries in a questioned document.


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Talk 5

Gold (I) Complexes Featuring Ferrocenylated N-Heterocyclic Carbenes for Anticancer Studies

Kevin Sidoran,1 Jonathan Arambula,2* and Kuppuswamy Arumugam1*

1Department of Chemistry, St. Bonaventure University, St. Bonaventure, NY 2Department of Chemistry and Biochemistry, Georgia Southern University, Statesboro, GA

Ferrocene-containing molecules have been shown to reduce a cell’s ability to proliferate by catalyzing the formation of ROS. Au-containing N-Heterocyclic carbenes have been shown to have high specificity in combating cancer cell lines by inhibiting selenoenzyme Thioredoxin Reductase (TrxR), a protein involved in anti-oxidant pathways. These two anti-proliferative moieties were joined to evaluate the synergistic anticancer properties. Three ferrocene containing NHC-annulated metal complexes have been synthesized, and preliminary cytotoxicity studies were performed.


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Talk 6

Synthesis of Novel Glassy Liquid Crystalline Compounds from Cholesterol Derivatives

Daniel Snyder, Derek Schall and Jason Wallace*

Department of Math and Natural Sciences, D’Youville College, Buffalo, NY

Liquid crystals are fluids exhibiting molecular order, as the molecules that comprise them align themselves to varying degrees and in varying ways. This alignment results in unique and desirable optical properties, though the fluid nature is not always beneficial. Glassy liquid crystals (GLCs) freeze these unique properties into the solid state without crystallization, which can be detrimental to the desired optical properties. The most successful approach to the synthesis of glassy liquid crystals involves bonding mesogenic pendants to a bulky core via a flexible aliphatic spacer.

GLCs are already used in optics today; however they are hindered by the fact that they usually require lengthy syntheses and expensive reagents. Our research attempts to synthesize a GLC compound in two reaction steps using cost-effective starting materials. Cholesterol derivatives have long been used in other liquid crystal applications. They are large, mesogenic compounds that are readily available from commercial sources.

Our approach is to attach cholesterol derivatives to an aromatic core via a flexible aliphatic spacer. This will allow the mesogenic molecules enough freedom to arrange themselves in a cholesteric formation while giving us the desired glassy state. Our recent efforts have attempted to attach estrone pendant molecules with propyl spacers to a trimesic acid core.

+

+


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Talk 7

Syntheses and Characterization of Fluoroborate Salts of Noble-Gas Fluorocations and the [O2]+

Cation

Sara J. Stonehouse, Jamie Haner and Gary J. Schrobilgen*

Department of Chemistry and Chemical Biology, McMaster University, Hamilton, ON

The noble-gas fluorides, XeF2, XeF4, XeF6, and KrF2, behave as fluoride-ion donors towards strong Lewis acid fluoride-ion acceptors such as MF5 (M = As, Sb). Previous work has shown that XeF2, KrF2, and XeF6

react with strong Lewis acids, forming [NgF][MF6] (Ng = Kr, Xe) and [XeF5][MF6] salts. Syntheses with weak fluoride-ion acceptors such as BF3 have not been extensively investigated nor have their structures been determined. In the present work, XeF2, KrF2, and XeF6 were reacted with BF3 to give the salts, [XeF][BF4], [KrF][BF4], [XeF5][BF4], and [Xe2F11][BF4]. Compounds were characterized using low-temperature Raman spectroscopy and single-crystal X-ray diffraction (SCXRD).

The [XeF5][BF4] and [Xe2F11][BF4] salts represent a relatively unexplored class of xenon fluorocation salts containing a non-octahedral anion that exhibits a restricted number of contacts with [XeF5]+ and [Xe2F11]+. In contrast with known monomeric salts containing octahedral and pseudo-octahedral anions such as [XeF5][fac-OsO3F3] and [Xe2F11][AuF6], [XeF5][BF4] is a chain structure where the [XeF5]+ cations are bridged by [BF4]– anions through Xe---F–B contacts, and [Xe2F11][BF4] forms Xe---F–B bridged tetramers containing two crystallographically inequivalent [Xe2F11]+ cations.

The Raman spectrum of [KrF][BF4] was obtained in aHF, but the compound could not be crystallized. Attempts to crystallize [KrF][BF4] from SO2ClF led to oxidation of the solvent and formation of [O2][BF4], which was previously only accessible by low-temperature X-ray radiation of O2 + F2 + BF3

and has now been characterized by SCXRD. Its previously reported reaction with Xe yielded the alleged Xe–B bonded compound, FXeBF2, which has never been confirmed, but is currently under investigation.


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Student Poster Presentations Time: 12:30-2:00 PM (College Center, Blue Lounge, 1st Floor) Poster 1. Erick J. Braham and Robyn E. Goacher*

Department of Biochemistry, Chemistry, and Physics, Niagara Universitry, NY Investigation of Synergistic Enzyme Degradation of Lignocellulose with TGA and ToF-SIMS

Poster 2. Peter C. Ho, Jocelyn Sinclair, Patrick Szydlowski, Philip J.W. Elder, Chris Gendy, Lucia M. Lee and Ignacio Vargas-Baca*


Supramolecular Chemistry of Iso-Tellurazole N-Oxides

Poster 3. Shaunna M. McLeod, Timothy Y. Tittiris, Kevin E. Siters and Janet R. Morrow* Department of Chemistry, University at Buffalo, SUNY, Buffalo, NY

Design of Iron(II) Selective Optical Sensors

Poster 4. Tyler A. Smith1, Caroline M. Rufo1, Yurii S. Moroz1, Olesia V. Moroz1, Jan Stӧhr2, Xiaozhen Hu3, William F. DeGrado3 and Ivan V. Korendovych1*

1Department of Chemistry, Syracuse University, Syracuse, NY Short Peptides Self-Assemble to Produce Catalytic Amyloids

Poster 5. Jesse R. Stroka* and Robyn E. Goacher Department of Biochemistry, Chemistry and Physics, Niagara University, NY

Capabilities of Time-of-Flight Secondary Ion Mass Spectrometry to Image Artificially Weathered Wood-Polymer Composites

Poster 6. Michael J. Swierczynski Jr., Kelly Grau and Joonyeong Kim* Department of Chemistry, SUNY Buffalo State College, Buffalo, NY

Forensic Analysis of Gasoline Residues on Household Samples by Gas Chromatography

Poster 7. Connor B. Tumiel, Joseph J. Lesh and Phillip M. Sheridan* Department of Chemistry and Biochemistry, Canisius College, Buffalo, NY

Laser Excitation Spectroscopy of CaO2CH and CaO2CCH3

Poster 8. Michael Spicuzza, Katie Cumpston, Amanda Beary and Qun Gu* Department of Chemistry, Edinboro University, Edinboro, PA

Corrections for Fluorescence Inner Filter Effects Using Micro-cuvettes


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Poster 9. Alexandra K. Van Hall, Stephanie A. Sander and Janet R. Morrow* Department of Chemistry, University at Buffalo, SUNY, Buffalo, NY

Zn2+-Selective Switch of Duplex to Hairpin DNA

Poster 10. Nicholas R. Zerby, Courtney L. Whitney and Robyn E. Goacher* Department of Biochemistry, Chemistry, and Physics, Niagara University, NY

Systematic comparison of Solid-Sampling Instrumental Methods to Detect the Enzymatic Degradation of Wood

Poster 11. Lauren Evans, Gabrielle Budziszewski and Sarah E. Evans* Department of Chemistry and Biochemistry, Canisius College, Buffalo, NY

What Makes Lyme Disease Tick? Impact of Amino Acid Mutations on DNA Binding of Master Regulator, BosR

Poster 12. John Ganley, Atahualpa Pinto, Zaara Sarwar and Christopher T. Nomura* Department of Chemistry, SUNY College of Environmental Science and Forestry, Syracuse, NY

Progress Towards the Kinetic Characterization of PhaG, a Putative Thioesterase in the Poly-[(R)-3-hydroxyalkanoate] Producing Organism, Pseudomonas putida

Poster 13. Kenneth Nguyen, Renjith Maracheril, Kuppuswamy Arumugam* Department of Chemistry, St. Bonaventure University, Saint Bonaventure, NY

Electro- and Spectroelectrochemical Characterization of Redox Active N-Heterocyclic Carbenes

Poster 14. Brandi M. Colon, Daniel Snyder and Kacie Liwosz* Department of Math and Natural Sciences, D’Youville College, Buffalo, NY

Synthesis of Mixed-Composition CdxZn1-xSe Quantum Dots

Poster 15. Sabrina Fitzgerald, James J. Rutowski, Jonathan A. Binns, Joseph M. Schnitter and Jeremy L. Steinbacher*

Department of Chemistry and Biochemistry, Canisius College, Buffalo, NY Toward a Multifunctional 19F MRI Contrast Agent Based on Mesoporous Silica Nanoparticles

Poster 16. Eric Helenbrook, Megan Cross and Kuppuswamy Arumugam* Department of Chemistry, St. Bonaventure University, St. Bonaventure, NY

Regulating the Ring Size of Cyclic Polyesters Using Electrochemical Techniques.


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Poster 17. Kylie Majka, James Lioi, Mark Gallow, Luis Sanchez and Stephanie Scharmach* Department of Biochemistry, Chemistry, and Physics, Niagara University, NY

Antibacterial Activity of Piperine Derivatives Against Staphylococcus aureus

Poster 18. Jeffrey Suen, Laurent Goujon and Harald Stöver* Department of Chemstry and Chemical Biology, McMaster University, Hamilton, ON

Fabrication of Synthetic Hydrogels in 96-well Plates as Platform for High Content Analysis of Biological Assays

Poster 19. Daniel A. Van Oss, Austin Quinn and Joseph A. Gardella, Jr.* Department of Chemistry, University at Buffalo, SUNY, Buffalo, NY

Analysis of Keratinocyte Growth Factor Protein Uptake and Release on 2-Hydroxyethyl Methylacrylate (HEMA) Hydrogels Using Fluorescence Spectroscopy

Poster 20. Maoj J. Awad and Gregory R. Soja* Department of Math and Natural Sciences, D’Youville College, Buffalo, NY

Determining the Surface Coverage of Molecular Linkers on Nanocrystalline SnO2 Thin Films

Poster 21. Theodore Nguyen, Kevin Sidoran, Kenneth Nguyen and Kuppuswamy Arumugam* Department of Chemistry, St. Bonaventure University, St. Bonaventure, NY

Synthesis of Ferrocenylated N-Heterocyclic Carbene Silver (I) Complexes

Poster 22. Zachary Mariani, Stephanie Scharmach and Luis Sanchez* Department of Biochemistry, Chemistry and Physics, Niagara University, NY

Tuning Chemoselectivity Toward an Affordable Synthetic Route to Aurantioclavine

Poster 23. Lauren Lubecki and David T. R. Stewart* Department of Math and Natural Sciences, D’Youville College, Buffalo, NY

Comparing an Analytical Titration to a Commercial Kit to Determine the Hardness of Water

Poster 24. Rachel Sanger, Luis Sanchez and Stephanie Scharmach* Department of Biochemistry, Chemistry and Physics, Niagara University, NY

Characterization of Hydrazone Schiff Bases Derived from 2,4-Dinitrophenylhydrazine


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Poster 25. Dan Snyder and Kacie Liwosz* Department of Math and Natural Sciences, D’Youville College, Buffalo, NY

Investigating the Effect of Reaction Conditions on Growth of CdSe/ZnS Core/Shell Quantum Dots in Aqueous Solutions

Poster 26. Lauren VanGelder,1 Chris Milleville,1 Kate Pelcher,2 Sarbajit Banerjee2 and David F. Watson1*

1Department of Chemistry, University at Buffalo, SUNY, Buffalo, NY Functionalization of Single-crystalline β-PbxV2O5 Nanowires with Light-Harvesting Cys-CdSe Semiconductor Quantum Dots

Poster 27. Christopher Fritschi, Andrea Pascucci and Luis Sanchez* Department of Biochemistry, Chemistry, and Physics, Niagara University, NY

Developing a Synthetic Route to Caramboxin, a Rare Bioactive Non-Peptidic Amino Acid

Poster 28. Kristopher C. Kijanka, Scott J. Heller and Dominic L. Ventura* Department of Math and Natural Sciences, D’Youville College, Buffalo, NY

Wittig Olefination via Thermal Decomposition of Diazo Compounds


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Poster Abstracts

Poster 1

Investigation of Synergistic Enzyme Degradation of Lignocellulose with TGA and ToF-SIMS

Erick J. Braham and Robyn E. Goacher*

Department of Biochemistry, Chemistry, and Physics, Niagara Universitry, NY

The use of discrete enzymes and enzyme combinations in lignocellulose degradation is a powerful tool in biofuel and bioproduct production and research. The ability to accurately detect and assess the nature and extent of degradation caused by an enzyme or system of enzymes is important in development of more efficient degradation methods. This study investigates the ability of laccase, xylanase, and cellulase to work together to degrade lignocellulose more efficiently than discreet enzymes. This talk will focus on TGA and the analysis of TGA data. Using the methods of first derivative peak fitting and multivariet curve resolution (MCR) the method of TGA is shown to be a useful tool in detecting lignocellulose degradation. ToF-SIMS is analyzed via principal component analysis (PCA) in support of the TGA data.


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Poster 2

Supramolecular Chemistry of Iso-Tellurazole N-Oxides

Peter C. Ho, Jocelyn Sinclair, Patrick Szydlowski, Philip J.W. Elder, Chris Gendy, Lucia M.

Lee and Ignacio Vargas-Baca*


Molecules of the title compounds readily aggregate through strong Te-O secondary bonding interactions. In this way, a variety of supramolecular structures have been isolated and characterized by single-crystal X-ray diffraction, including polymers and macrocyclic tetra- and hexamers. Spectroscopic studies have demonstrated the existence of the cyclic structures in solution. These self-assembled macrocyclic super-molecules can act as ligands in coordination complexes and as fullerene receptors.


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Poster 3

Design of Iron(II) Selective Optical Sensors

Shaunna M. McLeod, Timothy Y. Tittiris, Kevin E. Siters and Janet R. Morrow*

Department of Chemistry, University at Buffalo, SUNY, Buffalo, NY

Iron (Fe) is the most abundant transition metal in the body, involved in many cellular functions. Uncertainty surrounds the cellular concentration of Fe(II), the likely oxidation state of free iron, as well as its role in transport, with clarity desired due to iron’s role in disease states. Fluorescent sensors are useful to probe these questions, with sensor design focused on selectivity for Fe(II) over other biologically relevant metals such as zinc (Zn(II)) and Fe(III). Using a macrocyclic recognition moiety, methods to tune selectivity were explored by examining the effects of varying donor atoms on the macrocycle as well as different pendant arms, which provide an additional binding site (Scheme 1). Binding properties for several ligands were studied through fluorescence titrations as well as paramagnetic 1H-NMR and pH potentiometric studies. Competition assays were used to determine binding constants with appropriate limits of detection. Binding constants for Fe(II) with 1,7-diaza-12-crown 4-ether were most promising, with pyridine pendant arms also showing increased selectivity for Fe(II). Synthesis of the sensors and progress towards optimizing our ligands will be discussed.

Scheme 1: Macrocycles feature either four nitrogen donors or two nitrogen and two oxygen donors. Pendant

arms include amides and pyridine. An example with Fe(II)

bound is shown.


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Poster 4

Short Peptides Self-Assemble to Produce Catalytic Amyloids

Tyler A. Smith1, Caroline M. Rufo1, Yurii S. Moroz1, Olesia V. Moroz1, Jan Stӧhr2, Xiaozhen

Hu3, William F. DeGrado3 and Ivan V. Korendovych1*

1Department of Chemistry, Syracuse University, Syracuse, NY 2Institute of Neurodegenerative Diseases and Department of Neurology, UCSF, San Francisco, CA

3Department of Pharmaceutical Chemistry, UCSF, San Francisco, CA

Enzymes carry out many extremely efficient catalytic functions. Underlying this efficiency is their extraordinary complexity and ability to fold into unique three-dimensional structures. Even after decades of research, attempts to replicate this efficiency through de novo design have only shown moderate success, and it is unclear how modern-day enzymes may have evolved1. However, short peptides that alternate hydrophobic and hydrophilic residues can self-assemble into amyloid fibrils to achieve well-defined secondary structure. These aggregates may have served as a template from which the first enzymes were derived2,3. We designed self-assembling seven-residue peptides that are able to act as Zn2+-dependent esterases4 (Figure 1). Zn2+ acts to both help induce fibril formation and to serve as a metal cofactor to catalyze acyl ester hydrolysis.

The ability of this simple system to catalyze a chemical reaction suggests that similar peptide aggregates may have been evolutionary precursors to modern-day enzymes. Additionally, the ability to use a minimalistic design approach to generate catalytic fibrils could have implications for the development of nanostructured catalysts. By using an alternating hydrophobic/hydrophilic template, novel functionality can be introduced into simple peptide aggregates. References: 1Korendovych, I. V. et al. Current Opinion in Structural Biology 2014, 27 (0), 113-121. 2Carny, O. et al. The FASEB Journal 2005, 19 (9), 1051-1055. 3Greenwald, J. et al. Journal of Molecular Biology 2012, 421 (4–5), 417-426. 4Rufo, C. M. et al. Nature Chemistry 2014, 6 (4), 303-309.

Figure 1. Self-assembling aggregates can be engineered to carry out enzyme-like catalysis


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Poster 5

Capabilities of Time-of-Flight Secondary Ion Mass Spectrometry to Image Artificially Weathered Wood-Polymer Composites

Jesse R. Stroka and Robyn E. Goacher*


Wood-polymer composites (WPCs) are an attractive material to use in building and decking because of their lower cost and environmental impact. There is a concern as to the long term integrity of WPCs, especially in outdoor applications. Some research into the durability of WPCs has shown support for the idea that the weakening of WPCs over time could be caused by a decreased interaction between the wood and polymer. It would therefore be of interest to learn more about the distribution of components (for example, coupling agents) at the wood-polymer interface. In this experiment, we set out to determine if the chemical imaging capabilities of a Time-of-Flight Secondary Ion Mass Spectrometer (ToF-SIMS) were an effective way of observing the degradation of WPCs. Commercial WPCs were obtained and weathered so as to simulate a year’s worth of exposure to rain, UV radiation, and freeze-thaw cycles, both alone and in combination. The surface of the samples was analyzed using a ToF-SIMS at five different stages of the weathering process. Topography was analyzed using a Scanning Electron Microscope (SEM) and the durability of the samples was measured at the end of weathering using flexural strength testing. Principal component analysis (PCA) and multivariate curve resolution (MCR) were utilized to compare the spectra and images of the samples obtained from the ToF-SIMS in order to estimate the extent of weathering for each sample relative to each other and a control.


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Poster 6

Forensic Analysis of Gasoline Residues on Household Samples by Gas Chromatography

Michael J. Swierczynski Jr., Kelly Grau and Joonyeong Kim*

Department of Chemistry, SUNY Buffalo State College, Buffalo, NY

Arson is an easy to commit crime. The required supplies are easily and cheaply available to the general public and no special knowledge such as hacking and marksmanship is required. It is also effective, as fires can quickly cause huge monetary damages and loss of life. Arson can be problematic to forensic investigators, as the nature of flames can destroy evidence such as fingerprints and hair at the scene of the crime. In nearly all cases of arson a liquid accelerant is used. Liquid accelerants, such as gasoline, speed up the process and increase the damage done during the time. Our research focuses on the detection of gasoline residues on different household samples over various intervals of time. For this goal, regular unleaded regular gasoline (87 octane number) and four common household materials: carpet, plywood, newspaper, and cotton fabric were chosen. These household samples were cut into the same size of pieces, a small amount of gasoline was splashed on them, and they were dried at room temperature for various time intervals prior to chemical analysis. Detection of gasoline residues from these samples were conducted via gas chromatography with headspace sampling and flame ionization detector. Our preliminary data has shown that a trace amount of gasoline could be identified from a cotton fabric sample even after 48 hours of staying at room temperature.


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Poster 7

Laser Excitation Spectroscopy of CaO2CH and CaO2CCH3

Connor B. Tumiel, Joseph J. Lesh and Phillip M. Sheridan*

Department of Chemistry and Biochemistry, Canisius College, Buffalo, NY

Spectroscopic studies of small metal-containing molecules in the gas phase offer insight into metal-ligand bonding. In a previous experimental investigation, the CaO2CH and CaO2CCH3 radicals were synthesized for the first time in the gas phase using a hot Broida-type oven source. Laser excitation spectroscopy was utilized to record low-resolution spectra of the A – X, B – X and C – X electronic transitions for both molecules. However, for each species the B – X and C – X transitions could not be resolved. Details regarding the geometry (planarity) and metal-ligand bonding (monodentate or bidentate) in each electronic state (X, A, B and C) could not be unambiguously determined from the spectra. Subsequently, we have synthesized these species using a molecular jet/laser ablation source for the first time. This technique produces molecules with a lower rotational temperature, thereby reducing spectral congestion. We have successfully recorded low-resolution spectra in which the B – X and C – X transitions are resolved for each molecule. Building on this work we plan to record high-resolution, rotationally-resolved spectra of the B – X and C – X transitions in order to determine the geometric and bonding characteristics of these species.


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Poster 8

Corrections for Fluorescence Inner Filter Effects Using Micro-cuvettes

Michael Spicuzza, Katie Cumpston, Amanda Beary and Qun Gu*

Department of Chemistry, Edinboro University, Edinboro, PA

For a commercial fluorimeter with right angle geometry, observed fluorescence suffers from attenuation and/or distortion due to Inner Filter Effects (IFEs) when sample concentration is not dilute. The attenuation caused by absorption of excitation radiation is called primary IFE (pIFE) and the attenuation caused by absorption of emission radiation is called secondary IFE (sIFE). Previous publications on IFE corrections were based on regular cuvettes (1cm in width). Under the right angle geometry, pathlengths of excitation and emission beams (x1 and y1) is related to cuvette width (w). Under same instrument setting, a micro-cuvette, with a width 50% or less than that of a regular cuvette, is expected to have much smaller pathlengths of the excitation/emission beams. Hence the observed fluorescence intensity of a sample in micro-cuvettes is expected to suffer much less from IFEs. In this work, we aim to improve IFE corrections using micro-cuvettes (5mm or less in width). We will compare results to those obtained using regular cuvettes. A Horiba Fluormax-4 fluorimeter is used to obtain fluorescence intensity and a Shimadzu UV2600 spectrophotometer is used for absorbance measurements needed for IFE corrections.


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Poster 9

Zn2+-Selective Switch of Duplex to Hairpin DNA

Alexandra K. Van Hall, Stephanie A. Sander and Janet R. Morrow*


Metal ion sensors are utilized in many biomedical applications. Sensors that are selective and sensitive to a specific molecule or ion are in demand for biomedical and chemical applications. DNA sequences that undergo large changes in secondary structure upon binding with small molecules serve as the basis for molecular switches. A Zn2+ complex has been found to promote the conversion of a fully complementary DNA double helix into DNA hairpins. The DNA switch was analyzed by a molecular beacon approach (utilizing fluorescence resonance energy transfer [FRET]), polyacrylamide gel electrophoresis, thermal melting experiments, and isothermal calorimetry. The conformational switch is promoted by both an isolated Zn2+ complex or by free ZnCl2 and a macrocyclic ligand. The switch is selective for Zn2+ over biologically relevant transition metal ions including Cu2+ and Fe2+. The dual ligand/DNA switch is an approach that may improve selectivity for metal-ion-sensing applications.


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Poster 10

Systematic Comparison of Solid-Sampling Instrumental Methods to Detect the Enzymatic

Degradation of Wood

Nicholas R. Zerby, Courtney L. Whitney and Robyn E. Goacher*

Department of Biochemistry, Chemistry, and Physics, Niagara University, NY

In order for lignocellulosic derived molecules to become a feasible and eco-friendly primary source for biofuels and chemicals in the future, we must start not only by determining the optimal experimental conditions for degradation of complex plant matter, but must also develop instrumental methods to detect and quantify such degradation. In this work, we investigate the degradation of both hardwood (birch) and softwood (spruce) samples using enzymes (cellulase, laccase and xylanase) to break down their cellulose, lignin, and hemicellulose components, respectively. The instrumental methods used to quantify the enzymatic degradation were chosen to minimize sample preparation and include: Thermo-gravimetric Analysis (TGA), Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS), and Fourier Transform Infrared Spectroscopy (FTIR). All of these instruments are able to analyze solid and generally untreated lignocellulose samples, accommodating its inherent difficulty in solvating. Our goals are both to determine which instrumental method is most sensitive for our purposes, as well as to determine which conditions lead to the most thorough and efficient degradation of wood. To this last point, comparisons of unextracted versus extracted wood samples will be made in order to determine if removing small molecules in the wood would change the ease with which degradation is monitored, or otherwise alter the extent of degradation.


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Poster 11

What Makes Lyme Disease Tick? Impact of Amino Acid Mutations on DNA

Binding of Master Regulator, BosR

Lauren Evans, Gabrielle Budziszewski and Sarah E. Evans*


Lyme disease, caused by the bacteria Borrelia burgdorferi, is the fastest growing and most common tick-borne illness in the United States. B. burgdorferi is transferred to humans via tick bites and infection can cause long term illnesses including chronic arthritis. To survive the numerous environments it encounters during its life cycle, B. burgdorferi has complex regulatory pathways to deal with the stress of changing temperatures, pH, oxidization environments, and blood compositions between hosts. The Borrelia oxidative stress regulator, BosR, is a regulatory transcription factor that is vital to the survival of B. burgdorferi in all of its hosts. It functions to activate and repress nearly 80 genes, including genes for DNA protection from damage during starvation or oxidative stress and control over the expression of outer membrane proteins which are important for colonization in mammals. The goal of this research is to rigorously characterize the metal binding properties of BosR and to determine the relationship between metal and DNA binding. Classification of the metal interactions, along with identification of a specific Bos box, will aid in discovering additional genes that may be under the control of BosR and provide further understanding into the workings of this disease. This work determines the role of the amino acid in the position 39 of the protein, a common mutation observed, in DNA binding. The differences between the wild type and mutant binding to regulatory sequences of DNA show that the amino acid at position 39 is very important for binding interactions.


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Poster 12

Progress Towards the Kinetic Characterization of PhaG, a Putative Thioesterase in the

Poly-[(R)-3-hydroxyalkanoate] Producing Organism, Pseudomonas putida

John Ganley, Atahualpa Pinto, Zaara Sarwar and Christopher T. Nomura*

Department of Chemistry, SUNY College of Environmental Science and Forestry, Syracuse, NY

Poly-[(R)-3-hydroxyalkanoates] (PHAs) are biodegradable and biocompatible polyesters produced from intracellular fatty acid feedstocks by diverse microbial strains and genetically modified organisms. Increasing our understanding of different metabolic pathways within PHA-producing organisms is highly desired in order to bolster PHAs as an economically competitive alternative to petroleum-based plastics. Some pseudomonads, including P. aeruginosa, P. aureogaciens, P. putida, and others, commonly biosynthesize PHA polyesters composed of side chains containing between 6-14 carbons (medium chain length or MCL) from various sugars as carbon sources. The link between fatty acid biosynthesis and PHA production is the enzyme PhaG, which was previously reported to exhibit 3-hydroxyacyl-ACP:CoA transferase activity. Alternatively, recent studies have shown that PhaG can additionally function as a thioesterase, working in tandem with a MCL-fatty acid CoA ligase to produce MCL-PHA. In this study, plasmid vectors containing the phaG gene with either N or C terminal histidine tags have been constructed. From both constructs, PhaG fusion proteins were expressed in E. coli BL21(DE3), and purified by nickel affinity column chromatography. To test the enzyme’s catalytic activity, an N-acetylcysteamine (SNAC) thioester of rac-3-hydroxydecanoic acid was synthesized. Additionally, we’re carrying out the enantioselective syntheses of (R)-3-hydroxydecanoic acid and its SNAC analog via a Brown allylboration-based strategy. With our synthetic SNAC substrates in hand, we plan on carrying out a thorough kinetic analysis of PhaG with the hopes of settling the transferase/thioesterase controversy regarding the enzyme.


- 30 -

Poster 13

Electro- and Spectroelectrochemical Characterization of Redox Active N-Heterocyclic

Carbenes

Kenneth Nguyen, Renjith Maracheril and Kuppuswamy Arumugam*

Department of Chemistry, St. Bonaventure University, Saint Bonaventure, NY

Anti-cancerous properties have been found in molecules containing ferrocene. Research is being done to support the possible effects. We aim to investigate the properties of the two of the precursor NHC molecules. Two different N-heterocyclic carbene molecules having two ferrocene groups or one ferrocene group and 1 mesityl group were synthesized. Their characterizations, using Ultraviolet-visible spectroscopy, electrochemistry, and spectroscopic electrochemistry, are explored and reported. In future work, there is hope to report more data on similar N-heterocyclic carbene compounds with similar or different transition metals.


- 31 -

Poster 14

Synthesis of Mixed-Composition CdxZn1-xSe Quantum Dots

Brandi M. Colon, Daniel Snyder and Kacie Liwosz*


Quantum dots are nanoparticles that have the ability to absorb and emit at different wavelengths due to size-dependent properties. By adjusting things like temperature or varying the precursor ratio, it allows for changes in the size, which then affects the optical properties. My research focused primarily on synthesizing quantum dots with different properties by varying the precursor ratio. The synthesis ratios included 75/25 Zn/Cd; 50/50 Zn/Cd; 25/75 Zn/Cd. The goal is to repeat each synthesis and duplicate the data, allowing to control where the quantum dots absorb and then attempting to get them to grow further out in wavelength. We have successfully synthesized quantum dots that absorb between 400-520 nm in wavelength at their peak maximum. The fact that quantum dots have such versatile size-dependent optical properties makes them great for potential uses in luminescent imaging, which can include a range of things from in vivo imaging, diagnostics and even televisions.


- 32 -

Poster 15

Toward a Multifunctional 19F MRI Contrast Agent Based on Mesoporous Silica Nanoparticles

Sabrina Fitzgerald, James J. Rutowski, Jonathan A. Binns,

Joseph M. Schnitter and Jeremy L. Steinbacher*


Novel drug-delivery agents are needed to overcome the limitations of systemic toxicity of traditional chemotherapeutics, and an even more powerful paradigm combines delivery and imaging into one agent. One potential platform for such an agent is nano- or microparticles consisting of mesoporous silica, a well-characterized material with minimal toxicity and with great flexibility for chemical functionalization. Much progress has been made using porous silica particles as multifunctional drug-delivery agents, enabling combined delivery and imaging by incorporating contrast agents for optical detection, PET, and proton MRI. One imaging modality not yet combined with porous particles is 19F MRI.

Here, we present efforts to prepare multifunctional silica nanoparticles that incorporate fluorine atoms for detection by 19F MRI. We have synthesized several molecules that contain multiple, chemically-equivalent fluorine atoms in the form of trifluoromethyl groups. Importantly, the linkers contain a variety of hydrophilic moieties to promote solvation of the fluorine atoms. We have subsequently immobilized these groups to the pores of mesoporous silica nanoparticles that were PEGylated on their exterior surfaces to promote biocompatibility and water-dispersibility. Lastly, we used 19F NMR spectroscopy to detect these immobilized fluorine atoms and measure their magnetic relaxation properties, demonstrating proof-of-principle that 19F MRI could be used to detect and image these materials. Relaxation rates and signal-to-noise ratios were sufficient to acquire spectra in short amounts of time. In related work, we are preparing stimuli-responsive alkoxysilanes, which could be used to effect a “switch-on” response in 19F MRI, that respond to changes in pH or reducing conditions.


- 33 -

Poster 16

Regulating the Ring Size of Cyclic Polyesters Using Electrochemical Techniques

Eric Helenbrook, Megan Cross and Kuppuswamy Arumugam*

Department of Chemistry, St. Bonaventure University, St. Bonaventure, NY

Zwitterionic ring-opening polymerization (ROP) of lactones catalyzed by N-heterocyclic carbenes (NHC’s) has proven to yield cyclic polyesters. Currently, ring size is dependent on careful monomer addition. Although polymerization occurs with NHC catalysts, little is known about a more efficient ring size control using electrochemical techniques. Exploration of such polymerization is underway with metal bis(dithiolene) NHC adducts since they present a promising method to obtain cyclic polyesters with specialized cyclic architectures, control of ring size, and retain recyclability of NHC catalysts. Characterization of such bis(dithiolene) NHC adducts followed by electrochemical experimentation presents capable enhancement and optimization of polymerization techniques. This electrochemical approach for precision polyester synthesis may provide utility in industrial and biomedical purposes.


- 34 -

Poster 17

Antibacterial Activity of Piperine Derivatives Against Staphylococcus aureus

Kylie Majka, James Lioi, Mark Gallow, Luis Sanchez and Stephanie Scharmach*


Piperine, an alkaloid, is responsible for the pungency of black pepper and long pepper. New lengths have been reached in discovering the uses of piperine and its potential as an antibiotic. We expect by varying the amide functional group we will identify a molecule similar to piperine that has greater antibacterial activity against Staphylococcus aureus. Several piperine derivatives have been synthesized and fully characterized. Preliminary studies have shown no antibacterial activity against the bacteria S. aureus.

O

O

O

N

increase or decrease chain length

Vary aryl goup vary amide

funcationaly

Piperine


- 35 -

Poster 18

Fabrication of Synthetic Hydrogels in 96-well Plates as Platform for High Content Analysis of

Biological Assays

Jeffrey Suen, Laurent Goujon and Harald Stöver*

Department of Chemstry and Chemical Biology, McMaster University, Hamilton, ON Synthetic hydrogels have inherent advantages as extracellular matrices (ECM) due the tunability of physical properties to mimic soft tissues to serve as an ECM for attachment dependent biological cells.1 When implemented in 96-well plates, it serves as a method for high throughput screening.2 However, any height variations within a well, and across different wells, can interfere with current, highly automated, analyses using microscopy (Fig. 1). This study aims to develop uniform, flat crosslinked hydrogels by a reaction between poly(N-(3-aminopropyl)methacrylamide-co-N-(2-hydroxypropyl)methacrylamide) (PAPM) and poly(methyl vinyl ether-alt-maleic anhydride) (PMM) on (3-aminopropyl)triethoxysilane (APTES) functionalized glass bottom plates as a platform for cell studies. Glass covers slips together with microsphere spacers are used to limit tilt and height variations, producing flat hydrogels across 70% of films in a 40 well sample. Post-functionalization studies were performed to show the tunability of PAPM/PMM hydrogels. Post-treatment with ethylene diamine and aminoethanol were used to control gel swelling and surface charge, resulting in a flat hydrogel substrate free of surface features that is suitable for cell attachment. Ethylene diamine functionalized gels exhibited a reduced swelling degree while ethanolamine functionalized gels where shown to induce surface wrinkling features. This implementation of chemically versatile PAPM/PMM hydrogels as synthetic ECMs of consistent thicknesses in 96-well provides potential applications in efficient high throughput screening of biological assays.

1Nguyen, K. T.; West, J. L. Biomaterials. 2002, 23, 4307-43. 2Mih, J. D.; Sharif, A. S.; Liu. F.; Marinkovic, A.; Symer, M. M.; Tschumperlin, D. J. PLoS One. 2011, 6(5), 1-10.


- 36 -

Poster 19

Analysis of Keratinocyte Growth Factor Protein Uptake and Release on 2-Hydroxyethyl

Methylacrylate (HEMA) Hydrogels Using Fluorescence Spectroscopy

Daniel A. Van Oss, Austin Quinn and Joseph A. Gardella, Jr.*


Keratinocyte Growth Factor (KGF) is an important protein in skin healing. This experiment studies the rate at which KGF absorbs into and releases from a HEMA hydrogel that would potentially be part of a wound healing dressing. The protein is labelled with BODIPY STP fluorescent label to analyze the KGF in the fluorimeter, which would otherwise be invisible. This technique is used to monitor the uptake and release of the protein into/from the HEMA hydrogel for use in drug delivery to a wound.1

Another important aspect of the research is to determine the pore size of the hydrogels to be used as a dressing, how fast they dry-out, and under what circumstances. Since the hydrogels will be used to deliver KGF, it is important to know how quickly they release the KGF and how these characteristics of the hydrogel affect the release.

The following graph illustrates a calibration curve used to determine the concentration of KGF in a phosphate buffered saline solution that will be used to load the protein onto the hydrogel. The BODIPY STP fluorescent label is excited at 500nm and emits at 510nm.

1. Appawu, J. A. M. Model studies of diffusion-‐controlled (2-‐hydroxyethyl methacrylate) HEMA hydrogel membranes for controlled release of proteins. Ph.D. Dissertation, Univerity at Buffalo, SUNY, 2012.

-‐100

0

100

200

300

400

500

600

0 10 20 30 40 50 60

Intensity

Concentration of KGF in PBS (nM)

Calibration Curve for KGF


- 37 -

Poster 20

Determining the Surface Coverage of Molecular Linkers on Nanocrystalline SnO2 Thin Films

Maoj J. Awad and Gregory R. Soja*


The surface coverage of mercaptohexadecanoic acid (MHDA) adsorbed on nanocrystalline SnO2 thin films is presented. MHDA can act as a molecular linker in the attachment of quantum dots to the SnO2 film, which would have applications in sensing and photovoltaic devices. SnO2 thin films were prepared via a low cost doctor blade method, in which colloidal SnO2 is spread across a glass substrate using a pastuer pipette. Nanocrystalline films were achieved with an annealing step at 450°C. SnO2 films with an average thickness of 2 microns and an average particle size of 25 nm were characterized. Films were immersed in a 2 mM solution of MHDA in THF for at least 2 hours. Using FTIR spectroscopy, integrated absorbance was measured between 2800-3000 cm-1. This region is where the CH2 symmetric and asymmetric stretches occur from the surface adsorbed MHDA. Using a modified Beer-Lambert equation the surface coverage of MHDA on the SnO2 film was calculated to be 1.1 ± 0.1 x 10-7 mol/cm2, which closely agrees with previously reported surface coverages of MHDA on nanocrystalline TiO2 thin films. Future studies will explore the catalytic nature of these SnO2 films.


- 38 -

Poster 21

Synthesis of Ferrocenylated N-Heterocyclic Carbene Silver (I) Complexes

Theodore Nguyen, Kevin Sidoran, Kenneth Nguyen and Kuppuswamy Arumugam*

Department of Chemistry, St. Bonaventure University, St. Bonaventure, NY

We are investigating the use of ferrocenylated N-heterocyclic carbene supported silver complexes as anti-microbial agents. This study involves synthesis of several silver compounds with varying ferrocene groups, such as Fc0-NHC, Fc2-NHC, and Fc4-NHC. Silver complexes were prepared by treating Ag2O with corresponding imidazolium salts in acetonitrile at reflux. All reactions with the silver complexes were done in the absence of light. Using this route, we have successfully synthesized Fc0-NHC and Fc2-NHC supported silver complexes and their anti-microbial studies are underway.


- 39 -

Poster 22

Tuning Chemoselectivity Toward an Affordable Synthetic Route to Aurantioclavine

Zachary Mariani, Stephanie Scharmach and Luis Sanchez*


Aurantioclavine is a natural product isolated from Penicillium aurantiovirens that gained the interest of the synthetic community for its proposed role in the biosynthesis of the complex polycyclic alkaloids of the communesin family. Members of this family display notable bioactivities, including insecticidal properties and cytotoxicity toward leukemia cell lines.

Our interest in this important compound lies in its structural resemblance to tryptamine, a derivative of the amino acid tryptophan. Tryptamine is readily available and more than one hundred times less expensive than the starting materials used in the reported total syntheses of aurantioclavine. Therefore we aim to develop a rational reaction sequence to progressively transform tryptamine and access aurantioclavine synthetically. This approach, nevertheless, is bound to involve an “unfavored” cyclization in order to assemble aurantioclavine’s characteristic seven-membered ring. We expect to tune the chemical selectivity of this process via the functionalization of the indole ring and pendant chain of tryptamine—altering the geometry and electronics of the functionalities involved in the cyclization. Our progress in these efforts will be presented.


- 40 -

Poster 23

Comparing an Analytical Titration to a Commercial Kit to Determine the Hardness of

Water

Lauren Lubecki and David T. R. Stewart*

Math and Natural Sciences Department, D’Youville College, Buffalo, NY

Determining the hardness of water is useful for solving plumbing issues around the house, and saving money in repairs over time. The corrosion of pipes in a house, or that milky film on dishes and sinks are due to hard water; water with a high concentration of calcium and magnesium ions. By testing the level of hardness, further measures can be taken to remove those ions from the water. Well water tends to have higher hardness than tap water from Erie County, and softened water has very low hardness.

The calcium and magnesium ion concentration can be determined by titrating with ethylenediaminetetraacetic acid (EDTA). This study compares the results of an analytical titration, using UV/Vis spectroscopy to determine the endpoint, with a commercial testing kit where the endpoint is determined by eye. Each method was assessed for precision, accuracy, and ease of use. Though the kit is far simpler to implement, the analytical titration tends to be more accurate.


- 41 -

Poster 24

Characterization of Hydrazone Schiff Bases Derived from 2,4-Dinitrophenylhydrazine

Rachel Sanger, Luis Sanchez and Stephanie Scharmach*


A series of dinitrophenylhydrazones were prepared with (2,4-dinitrophenyl)hydrazine and 8 different “unknown aldehydes” (A-H). The unknown hydrazones were characterized by NMR, IR, and DSC. The purpose for this research was to develop experiments where sophomore organic chemistry students had to identify unknowns using more than just melting point analysis, but rather 1H NMR, 13C NMR and IR data as well. Most of the hydrazone products expressed similar melting points; therefore another characterization is needed for proper identification. Future research will include testing the hydrazone products to see if they exhibit any antibacterial activity for possible therapeutic purposes.

R O

NHNH2

N+O

-O N+O

O-+ -O

ON+

O-

ON+

N NH

R

H+


- 42 -

Poster 25

Investigating the Effect of Reaction Conditions on Growth of CdSe/ZnS Core/Shell Quantum

Dots in Aqueous Solutions

Dan Snyder and Kacie Liwosz*


Researchers of CdSe/ZnS core/shell quantum dots (QDs) are quickly finding uses in numerous applications. The global market for QDs is expected to grow by a factor of 10 or more within the next five years alone. Most of the better-known routes of synthesis rely on organic solvents and high temperatures. Aqueous routes of synthesis are much cheaper and environmentally friendly because they do not require much energy input or organic solvents. However these routes are not as well understood and differences in reaction conditions can have a huge impact on the distribution of particle sizes as well as the average size of the particles. Aqueous routes may become the primary method for growth of CdSe/ZnS core/shell with further research. We attempt to determine the impact of temperature, time, and reagent concentration on the growth of these core/shell QDs. We have found that upon addition of a ZnS precursor to pre-synthesized CdSe QDs, a broadening and slight red-shift occurs (see figure). This is consistent with minor changes in the optical properties of QDs with the addition of a shell with a large bandgap (compared to the core). This shift is dependent on whether the ZnS precursor is added in-situ to the CdSe reaction mixture, or added after isolation of the CdSe QDs. Further studies may provide additional evidence for the presence of a core/shell structure to our QDs.


- 43 -

Poster 26

Functionalization of Single-crystalline β-PbxV2O5 Nanowires with Light-Harvesting Cys-CdSe

Semiconductor Quantum Dots

Lauren VanGelder,1 Chris Milleville,1 Kate Pelcher,2 Sarbajit Banerjee2 and David F. Watson1*

1Department of Chemistry, SUNY at Buffalo, Buffalo, NY

2Department of Chemistry, Texas A&M University, College Station, TX

Lead vanadium oxide (β-PbxV2O5) is a semiconductor which has potential as a photocathode in photoelectrochemical cells due to its wide-band gap and mid-gap electronic states. This poster will report our results involving the functionalization of β-PbxV2O5nanowires with light-harvesting CdSe semiconductor quantum dots (QDs), toward the goal of promoting excited-state interfacial charge separation. Tunability in both the mid-gap states of the nanowires and the band gap of QDs allows for band alignment at the nanowire-QD interface, which results in a thermodynamic driving force for hole transfer from the valence band of the QD into the mid-gap states of the β-PbxV2O5 nanowires. The approach utilized for functionalization on nanowires is linker-assisted CdSe attachment via the bifunctional linker cysteinate(2-) (Cys). Preliminary results indicate promising evidence of linker attachment to β-PbxV2O5 nanowires.


- 44 -

Poster 27

Developing a Synthetic Route to Caramboxin, a Rare Bioactive Non-Peptidic Amino Acid

Christopher Fritschi, Andrea Pascucci and Luis Sanchez*


While safe for everyone else, ingestion of Averrhoa carambola, more commonly known as star fruit, can be harmful to chronic kidney disease patients; symptoms such as vomiting, mental confusion, and seizures and even deaths have been reported. Caramboxin has been recently identified as the active compound responsible for these effects and its molecular structure has been determined to be an amino acid-like moiety resembling phenylalanine.

Our interest in caramboxin lies on its orsellinic acid-like aromatic ring, a feature present in a number of medically relevant natural products. These compounds and their analogues are currently being investigated for the treatment of malaria, menopause symptoms, and various forms of cancer. We envision that caramboxin, as an amino acid, has the potential to be incorporated in peptide-like compounds for the development of novel drugs. With this in mind, synthetic access to large quantities of this rare active amino acid for biological studies is highly desirable.

Given that the chirality of caramboxin has not been determined, the present project aims at its first total synthesis for structural confirmation. Furthermore, our synthetic route, which begins with aspartic acid, may provide a glimpse at how this molecule is produced in nature by Averrhoa carambola.


- 45 -

Poster 28

Wittig Olefination via Thermal Decomposition of Diazo Compounds

Kristopher C. Kijanka, Scott J. Heller and Dominic L. Ventura*

Math and Natural Sciences Department, D’Youville College, Buffalo, NY

The Wittig reaction to synthesize olefins is a very attractive method in organic synthesis. Recently, this methodology has been achieved utilizing simple metal catalysts and diazo compounds in addition to a phosphine and an aldehyde. We report, for the first time, this chemistry achieved through thermal decomposition of a diazo compound without any metal catalyst. The following work utilizes aldehydes and diazoacetates in the presence of various pnictogen compounds to undergo Wittig-like reactions. We examine the influence of substitution on the aromatic ring of the aldehyde as well as the influence of the phosphine, arsine or antimony complex. We have been able to exclusively synthesize the trans-olefins in excellent yields.

H

N2

OEt

ONo Metal Catalyst

XPh3 (1.1 equiv.), PhCF3, reflux, 1h(X = P, As, Sb)

O

CO2Et

CO2Et

cistrans1.1 equiv.

>20:1 ratio trans: cis

R

R R

R = H, Me, OMe, Ph, Cl, F, Br, CF3, NO2


- 46 -

NOTES: