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Chemistry

2019

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Full-Text Articles in Physical Sciences and Mathematics

Arsenoplatins - Potent Anticancer Agents Against Triple-Negative Breast Cancer, Denana Miodragovic Nov 2019

Arsenoplatins - Potent Anticancer Agents Against Triple-Negative Breast Cancer, Denana Miodragovic

Faculty Research and Creative Activities Symposium

Triple-negative breast cancer (TNBC) is a more aggressive breast cancer with a poorer prognosis than other types of breast cancer. TNBC mortality is 42% higher in African American women compared to other American women, which is one of the most significant examples of racial disparity in oncology. TNBC does not express the common receptors estrogen and progesterone or the human epidermal growth factor receptor 2 (HER2), making targeted hormone therapies ineffective. Thus, there is an urgent medical need for the development of novel potential drug candidates for TNBC. In clinics, platinum-based regimes provide overall survival advantages for TNBC patients compared …

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On The Apparent Attractive Interaction Between Colloidal Particles Of Like Charge, Stefan Tsonchev Nov 2019

On The Apparent Attractive Interaction Between Colloidal Particles Of Like Charge, Stefan Tsonchev

Faculty Research and Creative Activities Symposium

A new attractive force between colloidal particles of like charge has been discovered. This force is of entropic depletion origin, and is exhibited between colloidal particles in electrolyte solution. The attractive potential associated with this force is a function of the electrolyte concentration, and can have a minimum up to the order of -10 kT deep for certain parameters of the system. Implications of the force to various systems of interest will be discussed.

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Monitoring The Breakdown Of Plastic Materials Under Ultraviolet And Visible Light, Samantha Brown-Xu Nov 2019

Monitoring The Breakdown Of Plastic Materials Under Ultraviolet And Visible Light, Samantha Brown-Xu

Faculty Research and Creative Activities Symposium

The accumulation of plastic waste in landfills and especially in water systems is a pressing environmental concern. Every year, roughly 8 million tons of plastic waste escapes into the oceans, which over time can then break down into microplastics, less than a quarter inch in size, that are consumed by ocean wildlife. The plastic degradation can occur by mechanical means, but energy absorbed from sunlight is also involved in the breakdown of plastic materials. If the efficiency of this degradation was increased, solar energy could be used to eliminate plastic waste and regenerate fuels or chemical feedstocks. In this study, …

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2019 Women In Science Conference Program, Chicago Chec Nov 2019

2019 Women In Science Conference Program, Chicago Chec

Women in Science Conference

The Women in Science Conference celebrates women in the sciences. This year, the conference focuses on women in the field of chemistry, and will include keynote and plenary speakers, a career panel, a scientific art and media display and competition, hands-on chemistry-based learning activities, and a theater performance about Marie Curie by alumna Maria Bakalis.

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Performance Of Concrete Made With A Calcined Clay – Limestone-Portland Cement Exposed To Natural Conditions, Fernando Martirena, Ernesto Díaz, Dayran Rocha, Hamed Maraghechi, Karen Louise Scrivener Nov 2019

Performance Of Concrete Made With A Calcined Clay – Limestone-Portland Cement Exposed To Natural Conditions, Fernando Martirena, Ernesto Díaz, Dayran Rocha, Hamed Maraghechi, Karen Louise Scrivener

International Conference on Durability of Concrete Structures

This work presents the results of an investigation carried out to assess durability of concrete made with a calcined clay- limestone-Portland cement with 47% of clinker, hereafter named LC3, produced during an industrial trial in 2013. LC3 was used to cast concrete blocks and later expose them at a natural location at the northern coast of Cuba. Reference concrete was cast with Cuban Portland cement having 88% of clinker. Throughout three years (2015, 2016, 2017) concrete cores were systematically taken and the specimens were subjected to a testing program that included Formation factor, chloride profiling, surface resistivity, air permeability and …

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Root Cause Analysis And Method Development Of Calorimetry Experiments, Anya M. Deaton, Lydia R. Deaton, John M. Farrar Dr. Nov 2019

Root Cause Analysis And Method Development Of Calorimetry Experiments, Anya M. Deaton, Lydia R. Deaton, John M. Farrar Dr.

Posters-at-the-Capitol

First year chemistry students learn a broad range of concepts that are also proven out in the lab environment. These concepts are a basis for a solid foundation for future chemistry learning. When the lab experiments don’t produce the expected results, students understanding in these concepts diminish and overall confidence and grades suffer. Our project details the root cause analysis and subsequent method development work for two experiments related to calorimetry; heat of solution and freezing point depression. The team sought to refine these experiments after finding that many of the students were unable to generate the expected results for …

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Near Real-Time Determination Of The Prevalence Of Cannabinoids, Cathinones, And Synthetic Opioids, Catherine O'Rourke, Bikram Subedi Oct 2019

Near Real-Time Determination Of The Prevalence Of Cannabinoids, Cathinones, And Synthetic Opioids, Catherine O'Rourke, Bikram Subedi

Scholars Week

Unregulated new psychoactive substances (NPS) in “pure” or “preparation” forms are designed to mimic the effects of controlled substances, and are introduced and reintroduced in the market as a cheap substitute of established regulated drugs in quick succession to loophole the law enforcement efforts on combating drugs. For example, carfentanil, a synthetic opioid activates the opioid receptors similar to morphine but it is astoundingly potent compared to a typical drug of abuse (100 times more potent than fentanyl and 10,000 times more powerful than morphine). Based on the cost- and time-intensive forensic analysis, National Drug Early Warning System reported the …

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High Functional Diversity Of Contaminated Soils From Liberty State Park, Nina M. Goodey Oct 2019

High Functional Diversity Of Contaminated Soils From Liberty State Park, Nina M. Goodey

Sustainability Seminar Series

Urban brownfields present an opportunity to study the functioning of degraded ecosystems. We investigated the soils of Liberty State Park in Jersey City, New Jersey, which once supported a major rail yard and port facility with docks for shipping cargo to New York City. ICP-MS and pyrolysis-GC-MS studies were used to show that our study site is contaminated with heavy metals and organic contaminants, including polycyclic aromatic hydrocarbons. We used fluorescence spectroscopy to measure soil enzymatic function at multiple locations within the brownfield and found the following types of sites: 1.) hotspots with high heavy metal concentrations and high extracellular …

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Determination Of Cannabinoids, Cathinones, And Synthetic Fentanyls Using Wastewater-Based Epidemiology, Catherine O'Rourke, Bikram Subedi Oct 2019

Determination Of Cannabinoids, Cathinones, And Synthetic Fentanyls Using Wastewater-Based Epidemiology, Catherine O'Rourke, Bikram Subedi

Posters-at-the-Capitol

Unregulated new psychoactive substances (NPS) in “pure” or “preparation” forms are designed to mimic the effects of controlled substances, and are introduced and reintroduced in the market as a cheap substitute for established regulated drugs in quick succession to loophole the law enforcement efforts on combating drugs. For example, carfentanil, a synthetic opioid activates the opioid receptors similar to morphine but it is astoundingly potent compared to a typical drug of abuse (100 times more potent than fentanyl and 10,000 times more powerful than morphine). Based on the cost- and time-intensive forensic analysis, National Drug Early Warning System reported the …

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There And Back Again: A Chemist Tale & The Lord Of The Ring Stands, Benjamin Blass Oct 2019

There And Back Again: A Chemist Tale & The Lord Of The Ring Stands, Benjamin Blass

Science Seminars

Students at universities and colleges are focused on achieving their degrees, but often wonder where their careers will take them once they leave the confines of the academic world. While some people’s careers are straight lines through to retirement, others are wandering paths that lead to unexpected outcomes and opportunities. In an effort to provide some insight into life after school. This lecture describes Dr. Blass’s career journey over his 25+ year career and highlights some of the lessons he learned along the way.

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Development And Evaluation Of A Hybrid Adi/Swh Model Pre-Laboratory Curriculum, Tabitha Alitz, Dawn Del Carlo Aug 2019

Development And Evaluation Of A Hybrid Adi/Swh Model Pre-Laboratory Curriculum, Tabitha Alitz, Dawn Del Carlo

Summer Undergraduate Research Program (SURP) Symposium

Previous Research:
• Students value each part of the pre-lab differently, struggle to connect all of the components, and therefore fail to see the big picture
• Students find the pre-lab moderately helpful in understanding both the concepts and mechanics of the lab, but find it less helpful at the end of the semester compared to beginning
• The cognitive load demands of the SWH pre-lab hinders students’ ability to participate in authentic scientific inquiry

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Synthesis Of Oligopyridine Ligands Directed Towards Water Soluble Metal Complexes For The Decomposition Of Organophosphates, Jeremy Bloch Jul 2019

Synthesis Of Oligopyridine Ligands Directed Towards Water Soluble Metal Complexes For The Decomposition Of Organophosphates, Jeremy Bloch

Landmark Conference Summer Research Symposium

Our experimental focus is on the design and synthesis of oligopyridine based ligands for the synthesis of metal complexes that will be used to detoxify model compounds of organophosphate-based nerve agents and/or pesticides by hydrolysis or by acting as oxidizing agents.

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Luminescent Metal-Organic Frameworks, Lucas Stehle, Kaitlyn Mercando Jul 2019

Luminescent Metal-Organic Frameworks, Lucas Stehle, Kaitlyn Mercando

Landmark Conference Summer Research Symposium

Metal-organic frameworks (MOFs), porous materials composed of metal ions and organic linkers, have broad applications in separation, small molecule storage, and catalysis. Luminescent metalorganic frameworks (LMOFs) hold great potential in the development of sensors, and, with their relatively straightforward syntheses that produce predictable, homogeneous, extended structures, should result in good sensor-to-sensor reproducibility and uniform response. In addition, subtle differences in overall LMOF structure, metal ion coordination, pore surfaces, and host-guest interactions within pores should have significant impact on observed photoluminescence and provide numerous strategies for analyte detection. Highlighted here is the development of LMOFs composed of zinc or zirconium ions …

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Synthesis Of An Amide-Based Extended Heterocyclic System Capable Of Hydrogen Bonding To Both The Adenine And Uracil In Dsrna For Rna Recognition Using Pna, John M. Talbott, Aubrey L. Maryniak Jul 2019

Synthesis Of An Amide-Based Extended Heterocyclic System Capable Of Hydrogen Bonding To Both The Adenine And Uracil In Dsrna For Rna Recognition Using Pna, John M. Talbott, Aubrey L. Maryniak

Landmark Conference Summer Research Symposium

The majority of information known about RNA is centered around coding RNA for its role in synthesizing proteins from DNA. However, noncoding RNA is also biologically relevant, showing importance in gene expression and catalyzing reactions. Peptide Nucleic Acids, or PNAs, are a promising tool that can be used to study noncoding RNA. PNAs can bind to double-stranded RNA forming a triple helix and are highly selective for specific sequences of dsRNA. A current limitation of PNA as a ligand is that traditional nucleobases only bind with high affinity to single purine residues on the RNA, as triplex formation relies on …

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Exploring The Synthesis Of Substituted Porphyrins, Christina Schnee Jul 2019

Exploring The Synthesis Of Substituted Porphyrins, Christina Schnee

Landmark Conference Summer Research Symposium

A current theme in our research laboratory is the development of low cost methods for the synthesis of lamellar vesicles as models for cell membranes. These vesicles, serving as simplified artificial cells, allow us to examine fundamental properties of the membrane including transport of materials across the membrane. Vesicles of varying size can also be employed as molecule delivery systems for a variety of compounds, including pharmaceuticals. We are especially interested in pharmaceuticals used in photodynamic therapy. This type of medical intervention entails delivery of a prodrug (one which is not initially bio-active). Upon exposure to a specific wavelength of …

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Synthesis And Characterization Of A Tris(Phenolate)Amine Ligand For The Production Of An Iron(Iii)-Centered Catalyst, Caden Pensak, Marie Heidledr, Abby Betar Jul 2019

Synthesis And Characterization Of A Tris(Phenolate)Amine Ligand For The Production Of An Iron(Iii)-Centered Catalyst, Caden Pensak, Marie Heidledr, Abby Betar

Landmark Conference Summer Research Symposium

The use of tris(phenol)amines in the synthesis of iron(III)-based catalysts has been essential to the production of semi-aromatic polymers from epoxides and cyclic anhydrides. In order to create the iron(III)-centered catalytic compound, (ArMeO)3NFe(DMAP), however, we must first be able to reliably create it’s uncoordinated organic ligand in high yields. The goal of this project is to find the variables that optimize the synthesis of the tris(2-hydroxy-4,6-dimethylbenzyl)amine using hexamethylenetetramine, 2,4-dimethylphenol, and catalytic amounts of p-toluenesulfonic acid. We have performed experiments on the molar ratios of reactants, atmosphere, temperature, purification, and stirring for the synthesis. We have also characterized the results via …

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Development Of A One-Pot Allylation And Claisen Rearrangement Of Acetaminophen By Applying Microwave Radiation, Brandon R. Tessier Jul 2019

Development Of A One-Pot Allylation And Claisen Rearrangement Of Acetaminophen By Applying Microwave Radiation, Brandon R. Tessier

Landmark Conference Summer Research Symposium

The Claisen rearrangement is a widely applicable organic reaction that involves the shift of a sigma bond across the pi-system of an allyl vinyl ether to produce allylated phenols. In this project, we aim to develop a microwave assisted allylation of a phenol, followed by a subsequent Claisen rearrangement in one pot. The goals of this project are three-fold. First, we aim to accelerate these reactions using microwave assisted organic synthesis because to date, microwave technology has been sparsely used in Claisen chemistry. Second, we aim to perform these reactions in a single pot, enhancing the simplicity and elegance of …

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Detection Of Heavy Metals By Colorimetric Nanoparticles, Rachel Molino, Michael Perzel Jul 2019

Detection Of Heavy Metals By Colorimetric Nanoparticles, Rachel Molino, Michael Perzel

Landmark Conference Summer Research Symposium

In the United States there are 6.1 million lead water service lines. This fact leaves many Americans in a precarious situation, as slight changes in the properties of their water supply (ex. pH), could result in the leaching of lead into their drinking water. Unfortunately, the average person does not have the ability to test for lead in water. This problem exists because current technologies for lead detection are expensive and require trained personnel. To address this issue, we propose a simple and inexpensive paper test for lead(II) in drinking water. This test will utilize polymer nanoparticles, which encapsulate a …

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Photoswitchable Self-Complementary Hydrogen Bond Arrays, Suendues Noori, James A. Wisner Jun 2019

Photoswitchable Self-Complementary Hydrogen Bond Arrays, Suendues Noori, James A. Wisner

Western Research Forum

Background: Photochromism is the reversible transformation of a chemical material to another form by the absorption of electromagnetic radiation (light), where the two metastable forms have distinct absorption spectra and other properties. Photochromism in materials allows for the switching of their function solely based on irradiation with light. Polymers are used frequently as the building blocks for materials as they are versatile, multifunctional, can carry charge and be processed by solution-based deposition methods. Supramolecular polymers share the same definition as polymers with the exception that they are held together by reversible and directional non-covalent interactions such as hydrogen bonds. Synthesizing …

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Using Molecular Dynamics To Study Qs21 Interactions And Penetration Of Lipid-Cholesterol Bilayers, Sarai Guerrero, Mikko Karttunen Jun 2019

Using Molecular Dynamics To Study Qs21 Interactions And Penetration Of Lipid-Cholesterol Bilayers, Sarai Guerrero, Mikko Karttunen

Western Research Forum

Saponins have been used as adjuvant agents for decades in vaccines and therapies, but none are as well studied or heavily used as QS-21. This achievement is notwithstanding the fact that QS-21 usage is limited by its stability, toxicity, and scarcity. These shortcomings have only pushed researchers to develop and experiment with artificial recreations of the saponin to harness its unique benefits. A considerable number of research hours have been poured into this topic, but like QS-21 there is a shortcoming here as well. The number of articles that look at QS-21 interactions with the bilayer or the conditions under …

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Bending Ternary Dihalides: A Single Functional Form For Linearization Energies, Supreeth Prasad, Kelling J. Donald Jun 2019

Bending Ternary Dihalides: A Single Functional Form For Linearization Energies, Supreeth Prasad, Kelling J. Donald

Arts & Sciences Student Symposium

Introduction

Although the bonding in the symmetric groups 2 and 12 dihalides (MX2) has been studied extensively1,2, remarkably little work –experimental or theoretical – has been done on the mixed (ternary) dihalides, MXY. Previously, a criterion3,4 based on atomic softness (σ) was proposed for the bending of MX2 and MXY molecules. We extend this softness criterion on the slate of the mixed dihalides and the predicted separation is achieved between the bent and linear structures with almost the same cutoff, and with quasilinear species straddling the boundary. In this work, we report a complete assessment of the bonding preferences and …

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Polycarbodiimides And Polyguanidines : Their Reactivity And Applications In Covalent Adaptable Networks, Alberto Melchor Bañales May 2019

Polycarbodiimides And Polyguanidines : Their Reactivity And Applications In Covalent Adaptable Networks, Alberto Melchor Bañales

Scholars Week

We have recently discovered a new chemical transformation in which N,N’,N’’ tri-substituted guanidines undergo a thermal exchange reaction. Kinetic investigations indicate that the transformation is first order with respect to the guanidine, indicating a dissociative mechanism in which a carbodiimide and amine are formed as intermediates. This new reaction has been applied to polymer systems. Polycarbodiimides were shown to undergo postpolymerization modification with amines to form polyguanidines at room temperature under an hour. Polyguanidines undergo the newly found chemical transformation to form different substituted polyguanidines. This exchange reaction will be applied to the preparation of a covalent adaptable network by …

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Engineering Sortase; Activity And Selectivity Of New Hybrid And Ancestral Variants Of Sortase A, Sarah Struyvenberg May 2019

Engineering Sortase; Activity And Selectivity Of New Hybrid And Ancestral Variants Of Sortase A, Sarah Struyvenberg

Scholars Week

Bacterial sortase enzymes are a beneficial tool in innovative mechanisms of protein engineering. However, important limitations to utilization of sortases for engineered purposes exist; namely, that sortase A (SrtA) is a relatively poor enzyme and very specific for the substrate containing LPATXG motif. Exciting previous work from our collaborators reveals that sortases from different species recognize different sequences and that activity can vary. Therefore, we wanted to create and investigate hybrid sortase enzymes between SrtA from S. aureus and Streptococcus pneumoniae, wherein we swapped a substrate-interacting loop between the beta-E and beta-F strands. Our hypothesis is that these residues are …

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Bottom-Up Shape Engineering Of Organic Molecular Single-Crystals, Griffin Reed May 2019

Bottom-Up Shape Engineering Of Organic Molecular Single-Crystals, Griffin Reed

Scholars Week

The ability to fabricate complex submicron-scale components from inorganic crystalline semiconductor materials such as c-Si enables countless modern technologies, from microelectromechanical systems to integrated circuits. For single-crystal molecular materials on the other hand, comparable approaches to defining micron- and submicron-scale structure are much less well developed, in part because weak intermolecular binding forces make molecular crystals vulnerable to damage by conventional techniques such as reactive ion etching, wet etching, and energetic beam milling. Here we show how the same weak forces that are problematic for top-down patterning of molecular crystals can be exploited to enable controlled bottom-up growth, by leveraging …

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Heavy Metal Detection With Bismuth Film Electrode, Jen Olivero, Iain Laprade, Gabby Servito Apr 2019

Heavy Metal Detection With Bismuth Film Electrode, Jen Olivero, Iain Laprade, Gabby Servito

Creative Activity and Research Day - CARD

The purpose of this project is to extend the application of stripping square-wave voltammetry to allow for the detection of various heavy metals in water samples, to include lead, cadmium, and zinc contaminants. Glassy carbon bismuth film electrodes proved to be more reliable than screen printed carbon electrodes for detection of heavy metals. Parameters were optimized to allow for the quantification of lead, zinc, and cadmium simultaneously in tap water along with an unknown Fromm water sample. Cadmium and thallium were found to be present at the same potential on the voltammogram; this prevented simultaneous detection of both metals. Bismuth …

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Effect Of A Coordinating Pyridine Moiety On The Sap And Tsap Isomer Populations Of Bimodal Lanthanide (Iii) Complexes, Marisa Poveda, Osasere M. Evbuomwan Apr 2019

Effect Of A Coordinating Pyridine Moiety On The Sap And Tsap Isomer Populations Of Bimodal Lanthanide (Iii) Complexes, Marisa Poveda, Osasere M. Evbuomwan

Creative Activity and Research Day - CARD

Paramagnetic Chemical Exchange Saturation Transfer (PARACEST) agents are lanthanide complexes that generate contrast through the slow-to-intermediate exchange of paramagnetically-shifted protons or water molecules. Although PARACEST agents have shown promise as molecular imaging agents, in-vivostudies have been limited due to the masking of the CEST signal by spin-relaxation exchange (T2ex) and Magnetization Transfer (MT) effects. The majority of PARACEST agents studied to date have been Ln(III)DOTA-tetraamides which can either adopt the square antiprismatic (SAP) or twisted square antiprismatic (TSAP) geometries in solution. The more compact nature of the SAP isomer, combined with its slower bound-water exchange kinetics, makes …

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Electropolymerization Of Polyaniline In The Presence Of Ferricyanide, Farhad Akrami, Lucas Marinelli, Ryan M. West Apr 2019

Electropolymerization Of Polyaniline In The Presence Of Ferricyanide, Farhad Akrami, Lucas Marinelli, Ryan M. West

Creative Activity and Research Day - CARD

Here, we demonstrate that electropolymerization of aniline in the presence of ferricyanide leads to incorporation of the ferricyanide anions into the resulting polyaniline (PANI) film and an increase of the apparent deposition rate. Simultaneous cyclic voltammetry (CV) and quartz crystal microbalance (QCM) measurements in background electrolyte show a change in counter ion ingress/egress during oxidation and reduction of the film: an “inverted” mass transport behavior is observed, suggesting a cation-exchange mechanism for maintaining charge neutrality during oxidation of the leucoemeraldine to emeraldine state of the polymer. The behavior of the PANI-ferricyanide film is compared with films polymerized in the presence …

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The Effects Of Ph On The Kinetics Of The Follow-Up Reaction Of Dopamine O-Quinone, Cyril Fong, Ziming Dong Apr 2019

The Effects Of Ph On The Kinetics Of The Follow-Up Reaction Of Dopamine O-Quinone, Cyril Fong, Ziming Dong

Creative Activity and Research Day - CARD

The electrochemical studies of dopamine have been conducted for many years due to dopamine’s importance as a neurotransmitter and its function in daily life for individuals. Dopamine undergoes electrochemical redox reactions in which the different products can be detected by cyclic voltammetry.3 The focus of the experiments was to determine the pH range at which dopamine o-quinone would undergo cyclization as well as the relationship between the rate of cyclization as pH in the physiological range. The measurements were taken using a gold working electrode vs. a Ag/AgCl (1 M KCl) reference electrode. It was observed that the peaks …

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Effect Of Salt Concentration On Electrochemical Detection Of Dna, Ziming Dong, Eddie Madrigal, Ryan West Dr. Apr 2019

Effect Of Salt Concentration On Electrochemical Detection Of Dna, Ziming Dong, Eddie Madrigal, Ryan West Dr.

Creative Activity and Research Day - CARD

Electrochemical approaches for biological sensing offer the potential advantages of facile sample preparation, fast response times, ease of parallel and multiplexed measurements, and the possibility of miniaturization (of sample sizes, electrodes, and associated electronics). All of these factors contribute towards the feasibility of electrochemical methods in biological sensing and analysis. This potential has already been achieved with the commercialization of blood glucose meters, which often rely on an electrochemical transduction mechanism. We have previously demonstrated the ability to electrochemically detect and differentiate complementary and mismatched DNA using our method of melting DNA duplexes at electrified gold surfaces, i.e. e-melting. Recently, …

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Heavy-Atom Tunneling In The Planar Bond Shifting Of [16]Annulene, Philip Lampkin, Jon Shezaf Apr 2019

Heavy-Atom Tunneling In The Planar Bond Shifting Of [16]Annulene, Philip Lampkin, Jon Shezaf

Creative Activity and Research Day - CARD

Mid-sized annulenes are known to undergo rapid π-bond shifting. Given that heavy­atom tunneling plays a role in planar bond shifting of cyclobutadiene, we computationally explored the contribution of heavy­ atom tunneling to the planar bond shifting in the major (CTCTCTCT) and minor (CTCTTCTT) isomers of [16]annulene. (U)M06-2X/cc-pVDZ calculations yield bond-shifting barriers of ca. 10 kcal/mol. The results also reveal extremely narrow barrier widths, suggesting a high probability of tunneling for these bond-shifting reactions. Rate constants were calculated using canonical variational transition state theory (CVT) as well as with small curvature tunneling (SCT) contributions, via direct dynamics. For the major isomer, …

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