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Full-Text Articles in Chemistry

Moss Biomonitoring And Isotopic Signatures Reveal Aviation Fuel As Local Lead Source Near Oregon Airports, Oluwaseyi E. Aderinboye, Alyssa E. Shiel, Lauren Stalford, Christina J. Murphy, Dean B. Atkinson Aug 2026

Moss Biomonitoring And Isotopic Signatures Reveal Aviation Fuel As Local Lead Source Near Oregon Airports, Oluwaseyi E. Aderinboye, Alyssa E. Shiel, Lauren Stalford, Christina J. Murphy, Dean B. Atkinson

Chemistry Faculty Publications and Presentations

Lead emissions from piston-engine aircraft using leaded aviation gasoline (avgas) remain a significant source of environmental contamination near regional airports, posing potential health risks to nearby communities. Passive biomonitoring using the epiphytic moss Orthotrichum lyellii was combined with lead isotope fingerprinting to quantify lead concentrations and distinguish between legacy leaded gasoline and current avgas emissions near Hillsboro and Troutdale airports in Oregon. Here we show that lead levels are elevated by up to 50 times the rural background near airports, with isotopic signatures confirming avgas as a dominant local source. These findings indicate that avgas use contributes substantially to environmental …


Arylation Of Nitrogen, Oxygen And Carbon Nucleophiles By Aryl(Tmp)Iodonium Salts, Joseph Jordan Hatton May 2026

Arylation Of Nitrogen, Oxygen And Carbon Nucleophiles By Aryl(Tmp)Iodonium Salts, Joseph Jordan Hatton

Dissertations and Theses

Substituted aromatic rings are present in industry in a plethora of organic molecules such as pharmaceuticals, agrochemicals, materials and beyond. Therefore, methods for broadly installing aryl rings into other compounds to create substituted aromatic rings are valuable to many organic chemists. Historically these transformations are achieved through methods such as nucleophilic aromatic substitution and metal catalyzed cross-coupling. Nucleophilic aromatic substitution is a user-friendly method in this space but is limited by reliance on specific electronics. Metal catalyzed cross-coupling reduced the dependence on electronics in this space, but metals are generally unattractive reagents due to high costs, toxicity and challenges with …


Evaluating Acridones As Novel Therapeutics For Human Babesiosis, Pratap Vydyam, Elizabeth Zhang, Papireddy Kancharla, Rozalia A. Dodean, Jane X. Kelly Apr 2026

Evaluating Acridones As Novel Therapeutics For Human Babesiosis, Pratap Vydyam, Elizabeth Zhang, Papireddy Kancharla, Rozalia A. Dodean, Jane X. Kelly

Chemistry Faculty Publications and Presentations

Human babesiosis is an emerging tick-borne disease caused by Babesia parasites, most notably Babesia microti and Babesia duncani in North America and Babesia divergens in Europe. Infections can be severe or persistent or relapse despite treatment, and current therapeutic options remain limited, underscoring the urgent need for new and effective treatment options. Acridone derivatives originally developed as potent antimalarial agents against multiple life cycle stages of the malaria parasites were evaluated for their antibabesial activity using continuous in vitro culture systems of B. duncani and B. divergens. Lead candidates were assessed for selectivity against human cell lines to establish preliminary …


Toxicity, Chemistry, And Public Health Relevance Of Emerging Nicotine Analog Vapes, Pods, And Pouches., Rhea Raghu, Mohana Sengupta, Karen Lin, Felix Effah, Robert M. Strongin, Irfan Rahman Mar 2026

Toxicity, Chemistry, And Public Health Relevance Of Emerging Nicotine Analog Vapes, Pods, And Pouches., Rhea Raghu, Mohana Sengupta, Karen Lin, Felix Effah, Robert M. Strongin, Irfan Rahman

Chemistry Faculty Publications and Presentations

Electronic nicotine delivery system manufacturers, such as Charlie's Holdings Inc., ECBlend, Outlaw, and NicRiver, have recently introduced nicotine analogs, such as 6-methyl nicotine, 6-MN ("Metatine"), and nicotinamide, NA ("Nixamide," "Nixodine," or "Nixotin-free base and salt") in products to circumvent the U.S. FDA's premarket tobacco product application (PMTA) requirements. Marketed as "tobacco-free," "PMTA-exempt," or "FDA-approved," these compounds now appear in oral nicotine pouches and disposable bars/vapes from brands such as Outlaw Dip, Kumi-Six, SBX, Katchmi, and Spree Bar under proprietary labels including "NoNic6," "Metatine," or "NIC-SAFE." These products often mimic the appeal of conventional nicotine delivery systems, with extensive use of …


Analysis Of Novel Cannabis Products Labeled As Containing Thc-Jd, Kaelas R. Munger, Carlton C. B. Bone, Killian M. Anreise, Robert M. Strongin Mar 2026

Analysis Of Novel Cannabis Products Labeled As Containing Thc-Jd, Kaelas R. Munger, Carlton C. B. Bone, Killian M. Anreise, Robert M. Strongin

Chemistry Faculty Publications and Presentations

Objective:

THC-JD (tetrahydrocannabioctyl) is a semi-synthetic cannabinoid with an eight-carbon C3 side chain, present in only trace amounts in hemp, requiring synthesis for commercial use. It has been promoted as potentially 19 times more potent than delta-9-THC, consistent with enhanced CB1 receptor affinities for cannabinoids with 7-8 carbon C3 side chains. While one peer-reviewed report identified THC-JD (tetrahydrocannabioctyl) in Japanese online products, an anecdotal report from the U.S. suggests mislabeling. Method: To inform regulatory efforts and consumer awareness and to address these discrepancies, this study chemically analyzed five U.S. commercial cannabis vape products marketed as containing THC-JD. Results: Utilizing GC-MS …


Designing Novel Bisquinoline Antimalarials From Historical 4-Aminoquinolines To Combat Drug-Resistant Malaria, Mason J. Handford, Yuexin Li, Terry Riscoe, Xiaowei Zhang, Jane X. Kelly, Michael K. Riscoe Mar 2026

Designing Novel Bisquinoline Antimalarials From Historical 4-Aminoquinolines To Combat Drug-Resistant Malaria, Mason J. Handford, Yuexin Li, Terry Riscoe, Xiaowei Zhang, Jane X. Kelly, Michael K. Riscoe

Chemistry Faculty Publications and Presentations

Plasmodium falciparum, the deadliest causative agent of malaria, continues to evade eradication efforts through widespread drug resistance. The recent development of ADC-028, a 4-aminoquinoline antimalarial with excellent activity and pharmacokinetic properties, prompted the investigation of bisquinoline analogs featuring similar structural motifs. Here, we describe a structure-activity relationship study that guided the optimization of compounds with key features, including the 4-anilinoquinoline core and diverse bridging linkers. Several analogs exhibited potent in vitro activity (IC50 < 20 nM) against both drug-sensitive and multidrug-resistant P. falciparum strains, while maintaining favorable cytotoxicity profiles. Among them, 25 demonstrated improved intrinsic metabolic stability (t1/2 = 121 min) and potent in vivo efficacy (ED50 = 0.32 mg/kg/day), achieving complete curative protection at a reduced dose compared to ADC-028. While 25 showed moderately reduced oral bioavailability (F = 43%) and a shorter half-life (T1/2 = 27.2 h) relative to ADC-028, its enhanced in vivo efficacy underscores its therapeutic potential. This work highlights a promising path forward in developing antimalarials that retain the efficacy of legacy compounds while overcoming modern resistance mechanisms.


Nonenzymatic Glucose Biosensor Based On Selective Reduction Of Silver Ions, Maryam Sarlak, Shankar B. Rananavare Feb 2026

Nonenzymatic Glucose Biosensor Based On Selective Reduction Of Silver Ions, Maryam Sarlak, Shankar B. Rananavare

Chemistry Faculty Publications and Presentations

A nonenzymatic conductivity-based glucose biosensor, reported here, designed for potential noninvasive measurement in accessible biofluids such as saliva, sweat, and tears. The sensor exploits a classic Tollens’ silvering process that deposits metallic silver on a sensitized surface via a quantitative, selective reduction of silver ions by glucose. Of the two surface sensitization methods used, the self-assembled bifunctional thiol/silane surfactant yields a more stable and sensitive sensor than tin(II) chloride. The conductometric sensor consists of two spiral interdigitated silver electrodes fabricated by lithography and wet etching. The sensor impedance changes after selective metallic silver deposition between the electrodes. The sensor exhibits …


Selective Reversal Of Cu-Amyloid Aggregation Monitored In Real Time By Fluorescence Anisotropy: Ni-Bme-Dach Vs Edta Benchmarks, Alyssa N. Schroeder, Eleanor K. Adams, Dane C. Frost, Erica Lopez, Jennie R. Giacomini, Marilyn R. Mackiewicz Feb 2026

Selective Reversal Of Cu-Amyloid Aggregation Monitored In Real Time By Fluorescence Anisotropy: Ni-Bme-Dach Vs Edta Benchmarks, Alyssa N. Schroeder, Eleanor K. Adams, Dane C. Frost, Erica Lopez, Jennie R. Giacomini, Marilyn R. Mackiewicz

Chemistry Faculty Publications and Presentations

Metal dyshomeostasis, particularly involving Cu2+, is increasingly recognized as a key contributor to amyloid-β (Aβ) aggregation and neurotoxicity in Alzheimer’s disease, motivating the development of chelators capable of selectively disrupting pathogenic metal-Aβ interactions without perturbing essential biological metals. Here, we employ steady-state fluorescence anisotropy as a real-time probe of TAMRA-Aβ1–42 rotational mobility to quantify metal-induced aggregation and its reversibility by two chelators with distinct selectivities: EDTA, a broad-spectrum benchmark, and Ni-bme-dach, a sulfur-rich metallodithiolate with high Cu affinity. Cu2+ induces the most significant increases in anisotropy, consistent with rapid formation of large nanoscale aggregates, while Fe3+ produces moderate aggregation and …


The Gut Microbiota Shapes The Human And Murine Breath Volatilome, Ariel J. Hernandez-Leyva, Amalia Z. Berna, Maggie H. Bui, Yang Liu, Anne L. Rosen, Michael A. Lint, Samantha A. Whiteside, Natalia Jaeger, Nikhilesh Joardar, Wentai Luo, Multiple Additional Authors Jan 2026

The Gut Microbiota Shapes The Human And Murine Breath Volatilome, Ariel J. Hernandez-Leyva, Amalia Z. Berna, Maggie H. Bui, Yang Liu, Anne L. Rosen, Michael A. Lint, Samantha A. Whiteside, Natalia Jaeger, Nikhilesh Joardar, Wentai Luo, Multiple Additional Authors

Chemistry Faculty Publications and Presentations

The gut microbiota is crucial to health, yet implementation of microbiota-based therapeutics is limited by the lack of rapid diagnostics. We hypothesize that breath contains gut microbe-derived volatile organic compounds (VOCs) reflecting microbiota composition and metabolism. In healthy children, we found that breath VOC composition (or volatilome), assessed by gas chromatography-mass spectrometry, correlates with gut microbiome composition and function. By capturing exhaled breath from human-stool-colonized and monocolonized gnotobiotic mice, we profiled breath VOCs and discovered that murine breath is also significantly influenced by the gut microbiome. VOCs from cultured gut microbes were identified in vivo in monocolonized gnotobiotic colonized mice. …


Mechanistic Rationale For Toxic Aerosol Formation From Vaping And Dabbing With A Focus On Ketene Formation From Semi-Synthetic Cannabinoids, Kaelas Ryan Munger Sep 2025

Mechanistic Rationale For Toxic Aerosol Formation From Vaping And Dabbing With A Focus On Ketene Formation From Semi-Synthetic Cannabinoids, Kaelas Ryan Munger

Dissertations and Theses

Cannabis vaping is a relatively new route of administration that is increasingly common among youth and young adults. Cannabis vaping has been associated with cases of acute lung injury, especially among youth, and most often involves the heating and aerosolization of high-potency products having cannabinoid concentrations of ~ 50 % - 98 % w/w. Proponents argue that vaping is safer than smoking due to the characteristically lower temperatures and fewer plant materials. However, the extreme cannabinoid concentrations, along with non-natural formulations having undisclosed additives, require studies of the health effects of these products. Despite the popularity of cannabis concentrate vaping, …


Using The Epic (Exposure, Persuasion, Identification, And Commitment) To Develop A Measure Of Student Buy-In To Laboratory Learning Goals, Elizabeth Blanche Vaughan, A. Montoya-Cowan, Jack Barbera Aug 2025

Using The Epic (Exposure, Persuasion, Identification, And Commitment) To Develop A Measure Of Student Buy-In To Laboratory Learning Goals, Elizabeth Blanche Vaughan, A. Montoya-Cowan, Jack Barbera

Chemistry Faculty Publications and Presentations

Buy-in has been described as the series of judgements students make when deciding to engage with a pedagogical practice. Buy-in to pedagogical practices is known to have a meaningful impact on students’ engagement in learning environments, making it a construct of interest for researchers and practitioners. This study develops a measure of student buy-in to faculty defined laboratory learning goals by adapting an existing measure which operationalizes the construct in terms of Exposure, Persuasion, Identification, and Commitment (EPIC). The adapted measure presented in this study, deemed the EPIC-LaG (Laboratory Goals), was developed using learning goals for general and organic chemistry …


The Lewis Basicity Of Amines On The Legault Iodonium Lewis Acidity Scale., Soocheta Jha, Souradeep Basu, Madison Bob, David R. Stuart Jul 2025

The Lewis Basicity Of Amines On The Legault Iodonium Lewis Acidity Scale., Soocheta Jha, Souradeep Basu, Madison Bob, David R. Stuart

Chemistry Faculty Publications and Presentations

Diaryliodonium-amine complexes are proposed as key intermediates in metal-free C-N coupling reactions. Herein, H NMR titration is used to quantify association constants () between diaryliodonium triflates and synthetically relevant amines from which the amine Lewis basicity (LB) parameter is calculated. Compared to anionic Lewis bases, distinct solvent effects are observed.


Potent Acridone Antimalarial Against All Three Life Stages Of Plasmodium, Papireddy Kancharla, Rozalia A. Dodean, Yuexin Li, Xiaowei Zhang, Sean Kelly, Jordan Charlton, Angley Binauhan, Laurize Garcia, Diana Caridha, Jane X. Kelly, Multiple Additional Authors Jun 2025

Potent Acridone Antimalarial Against All Three Life Stages Of Plasmodium, Papireddy Kancharla, Rozalia A. Dodean, Yuexin Li, Xiaowei Zhang, Sean Kelly, Jordan Charlton, Angley Binauhan, Laurize Garcia, Diana Caridha, Jane X. Kelly, Multiple Additional Authors

Chemistry Faculty Publications and Presentations

New antimalarial therapeutics ideally should target all three major life cycle stages. Here we present an acridone antimalarial chemotype that is potent against blood, liver, and mosquito stages of malaria parasites, with the potential for single-dose cure of bloodstream infections, radical cure of liver infections, and blocking of transmission to mosquitoes. Attributes of lead candidate T111 include potent in vitro activity against cultured parasites, ex vivo activity against clinical isolates, oral single dose cure in an asexual blood stage rodent model, inhibition of sexual blood stage parasites, activity against relapsing parasites in non-human primate liver cells, prevention of parasite development …


Pvc Biodegradation Potential Of Native Fungal Strains From Mt. Hood National And Tillamook State Forests, Bristol Ozturgut Jun 2025

Pvc Biodegradation Potential Of Native Fungal Strains From Mt. Hood National And Tillamook State Forests, Bristol Ozturgut

University Honors Theses

Polyvinyl chloride (PVC) is a toxic, degradation-resistant environmental waste product. Recent research has revealed fungal enzymatic activity capable of biodegrading plastics. As PVC infiltrates local environments, it becomes imperative to determine the adaptability of local fungi to PVC substrates. In this experiment, 100 local native fungal strains sampled from the Tillamook State and Mt. Hood National forests and one commercial strain of common oyster mushroom were investigated for their ability to colonize and digest PVC by direct isolation on 0.1% and 0.2% PVC-enriched limited growth media. Substrates for positive cultures were imaged using Fourier transform infrared spectroscopy to analyze potential …


Cannabis Concentrate Vaping Chemistry, Kaelas R. Munger, Killian M. Anreise, Robert M. Strongin Jun 2025

Cannabis Concentrate Vaping Chemistry, Kaelas R. Munger, Killian M. Anreise, Robert M. Strongin

Chemistry Faculty Publications and Presentations

Background:

This review article addresses the vaping chemistry of manufactured cannabis concentrates—a topic that remains under-researched despite the widespread availability and growing popularity of these products. Given their current prevalence and the fact that many of the findings discussed herein are from early-stage investigations, further research is essential to fully assess the public health risks associated with concentrate use. The purpose of this article is to help begin to bridge this knowledge gap by outlining the technical challenges of studying cannabis concentrates and to present evidence-based data concerning toxicant exposures as a foundation for future investigations.

Methods:

A search of …


Investigation Into Thermodynamic And Kinetic Phenomena In Arylation Reactions With Diaryliodonium Salts, Soocheta Jha Jun 2025

Investigation Into Thermodynamic And Kinetic Phenomena In Arylation Reactions With Diaryliodonium Salts, Soocheta Jha

Dissertations and Theses

Benzenoid rings are fundamental structural motifs in organic chemistry, widely recognized for their prevalence in natural products, pharmaceuticals, agrochemicals, and functional materials. Transition metal-catalyzed arylation, using catalysts such as palladium, nickel, or copper, has revolutionized C-C, C-O, and C-N bond formation, offering broad substrate scope and high efficiency. Among the reagents developed for efficient aryl group transfer, diaryliodonium salts have emerged as particularly powerful tools. Diaryliodonium salts facilitate metal-free arylations across a broad spectrum of nucleophiles, offering high reactivity, operational simplicity and environmental compatibility. The versatility of diaryliodonium salts has led to their widespread adoption as efficient arylating reagent in …


Early-Stage Detection Of Copper Ion Release From Bronze Corrosion Using Uv/Vis Spectroscopy And Hydrogel Sensing, Hibah Khan Jun 2025

Early-Stage Detection Of Copper Ion Release From Bronze Corrosion Using Uv/Vis Spectroscopy And Hydrogel Sensing, Hibah Khan

University Honors Theses

Detecting copper(I) (Cu⁺) release at early corrosion stages is important for preserving bronze heritage materials. This study investigated the use of neocuproine (NC), a Cu⁺-specific ligand, for simple and selective colorimetric detection of Cu⁺ in solution. NC reacts with Cu⁺ to form a Cu(NC)₂ complex, which produces a distinct orange-red color with peak absorbance at 455 nm. Solutions were prepared with varying concentrations of Cu⁺ generated by reducing Cu²⁺ with excess ascorbic acid. Ultraviolet/Visible (UV/Vis) spectroscopy was used to quantify absorbance changes. The absorbance at 455 nm increased linearly across the tested Cu⁺ concentration range (6.25–200 µM) with an R² …


Identifying Antimalarials That Disrupt Malaria Parasite Transmission When Fed To The Mosquito, Sarah N. Farrell, Anton Cozijnsen, Vanessa Mollard, Papireddy Kancharla, Rozalia A. Dodean, Jane X. Kelly, Geoffrey I. Mcfadden, Christopher D. Goodman May 2025

Identifying Antimalarials That Disrupt Malaria Parasite Transmission When Fed To The Mosquito, Sarah N. Farrell, Anton Cozijnsen, Vanessa Mollard, Papireddy Kancharla, Rozalia A. Dodean, Jane X. Kelly, Geoffrey I. Mcfadden, Christopher D. Goodman

Chemistry Faculty Publications and Presentations

A decade-long decline in malaria cases has plateaued, primarily due to parasite drug resistance and mosquito resistance to insecticides used in bed nets and indoor residual spraying. Here, we explore the innovative control strategy targeting Plasmodium with antimalarials during the mosquito stages. This strategy has the potential to reduce the risk of resistance emerging because a relatively small population of parasites within the mosquito is subject to selection. After validating mosquito feeding strategies, we screened a range of parasiticidal compounds by feeding them to mosquitoes already infected with mouse malaria (P. berghei). Three antimalarials showed activity against P. berghei in …


Enabling New Synthetic Platforms For Aryne Synthesis With Aryl Thianthrenium Reagents, Riley Augustus Roberts May 2025

Enabling New Synthetic Platforms For Aryne Synthesis With Aryl Thianthrenium Reagents, Riley Augustus Roberts

Dissertations and Theses

The enormous importance of aromatic rings in organic molecules cannot be understated. Aromatic rings are present in the majority of pharmaceuticals, agrochemicals, and consumer products. The way in which these rings are arranged and substituted results in a molecule’s unique properties. Because of this, the current limitations of the chemical methods used to synthesize these molecules results in limited structural diversity and thus missed opportunities for the development of value-added products. To this end, this work demonstrates novel methods of aryne synthesis, aryl thianthrenium synthesis and a unique approach to structural scaffold hopping. The approaches presented herein allow for rapid …


The Role Of Homocysteine Redox Chemistry In Biomolecular Mechanisms, Megha Gupta Mar 2025

The Role Of Homocysteine Redox Chemistry In Biomolecular Mechanisms, Megha Gupta

Dissertations and Theses

Homocysteine at elevated levels is a well-known independent risk factor for cardiovascular disease. However, it is still unclear, after large scale clinical trials, involving tens of thousands of patients, whether homocysteine is a disease mediator or marker. The disconnect between the basic science showing the association of homocysteine with cardiovascular disease and the outcomes of clinical trials based on vitamin therapy for homocysteine lowering, highlights the need for insights into the molecular mechanisms linking homocysteine to cardiovascular disease and other pathologies. For example, elevated homocysteine levels have also been associated with risk for stroke, venous thromboembolism, Alzheimer's disease, neural tube …


Access To Arynes From Arenes Via Net Dehydrogenation: Scope, Synthetic Applications And Mechanistic Analysis, Riley A. Roberts, Bryan E. Metze, Nicole Javaly, Theresa M. Mccormick, David R. Stuart Feb 2025

Access To Arynes From Arenes Via Net Dehydrogenation: Scope, Synthetic Applications And Mechanistic Analysis, Riley A. Roberts, Bryan E. Metze, Nicole Javaly, Theresa M. Mccormick, David R. Stuart

Chemistry Faculty Publications and Presentations

Arynes undergo a wide range of chemical transformations making them versatile reactive intermediates for organic synthesis. Access to arynes has long been dominated by pre-functionalised reagents, e.g., the venerable o-trimethylsilylaryl triflates. However, a move toward developing methods to access arynes that are both mild and efficient has prompted research into aryl “onium” aryne precursors. Here, we leverage aryl “onium” species as in situ or isolated intermediates in a net dehydrogenation of simple arenes as a novel and efficient way to access arynes. We describe a unified strategy in which two different tactics are employed to access diversely substituted …


Photocathodes From Aerobic Oxidation Of Tellurorhodamines, Amelia Jellison Feb 2025

Photocathodes From Aerobic Oxidation Of Tellurorhodamines, Amelia Jellison

Dissertations and Theses

Growing environmental concerns have facilitated an increased need for renewable energy. Solar energy is an excellent source of renewable energy, however current dye-sensitized solar cells are not efficient enough for commercial use. This thesis attempts to create a novel dye-sensitized cathode to increase the efficiency of dye-sensitized solar cells.

Dye-sensitized cathodes could lower the energy level on the cathode and thereby increase the overall efficiency of the solar cell, however until now it has not been attempted. A tellurorhodamine dye with a mesityl ring was chosen as the dye for its ability to aerobically oxidize in the presence of light. …


Understanding Anionic Hyperporphyrins: Tddft Calculations On Peripherally Deprotonated Meso-Tetrakis(4-Hydroxyphenyl)Porphyrin., Jeanet Conradie, Carl C. Wamser, Abhik Ghosh Jan 2025

Understanding Anionic Hyperporphyrins: Tddft Calculations On Peripherally Deprotonated Meso-Tetrakis(4-Hydroxyphenyl)Porphyrin., Jeanet Conradie, Carl C. Wamser, Abhik Ghosh

Chemistry Faculty Publications and Presentations

Presented herein is a DFT/TDDFT study of -tetrakis(4-hydroxyphenyl)porphyrin (H[THPP]) and its Meso-deprotonated tetraanionic form; the latter was modeled as both a free tetraanion and with various counterions. Based on our calculations, the experimentally observed hyperporphyrin spectra are attributed to an admixture of phenol/phenoxide character into the a-type HOMO of tetraphenylporphyrin. The admixture results in an elevation of the orbital energy of the HOMO in relation to other frontier orbitals, which accounts for the observed spectral redshifts. The calculations underscore differences in the performance of different exchange-correlation functionals. Thus, while the popular hybrid functional B3LYP greatly exaggerates the redshift of …


Investigating Student Expectations, Buy-In, And Engagement In Lower Division Undergraduate Chemistry Labs, Elizabeth Blanche Vaughan Dec 2024

Investigating Student Expectations, Buy-In, And Engagement In Lower Division Undergraduate Chemistry Labs, Elizabeth Blanche Vaughan

Dissertations and Theses

Laboratory courses constitute an integral aspect of chemistry education at the undergraduate level. Despite their prominence, a growing number of researchers have begun to think more critically about the value of laboratory learning experiences. As pedagogical decisions should be based on evidence, it is necessary for chemistry education researchers and practitioners to investigate the claim that teaching laboratories are a valuable part of science education. Therefore, the aim of this dissertation was to address one small section of this gap in the literature by obtaining a more robust understanding of students' expectations, buy-in, and engagement in lower division, undergraduate, chemistry …


Increased Thermal Stability And Retained Antibacterial Properties In A Sulbactam And Amantadine Salt: Towards Effective Antibacterial-Antiviral Combination Therapies, Josephine Bicknell, Ivan Bondarenko, Alice Colatrella, Elani J. Cabrera-Vega, Jesus Daniel Loya, Delbert S. Botes, Jay L. Mellies, Gonzalo Campillo-Alvarado Dec 2024

Increased Thermal Stability And Retained Antibacterial Properties In A Sulbactam And Amantadine Salt: Towards Effective Antibacterial-Antiviral Combination Therapies, Josephine Bicknell, Ivan Bondarenko, Alice Colatrella, Elani J. Cabrera-Vega, Jesus Daniel Loya, Delbert S. Botes, Jay L. Mellies, Gonzalo Campillo-Alvarado

Chemistry Faculty Publications and Presentations

A clinically relevant multidrug solid comprising sulbactam (β-lactamase inhibitor) and amantadine (antiviral) displays enhanced thermal stability and sustained antibacterial activity compared to starting materials.

We describe the formation of a multidrug salt comprising sulbactam (SUL, β-lactamase inhibitor) and amantadine (AMNH, antiviral). Physicochemical investigation of the SUL·AMNH salt revealed enhanced thermal stability compared to pristine starting materials. In vitro studies found that salt formation in SUL·AMNH does not disrupt antibacterial activity against model organisms Escherichia coli and Staphylococcus epidermidis. To our knowledge, we show the first β-lactamase inhibitor-antiviral salt where both components have been approved by the U.S. Food and Drug …


Aars Online: A Collaborative Database On The Structure, Function, And Evolution Of The Aminoacyl-Trna Synthetases, Jordan Douglas, Haissi Cui, John J. Perona, Oscar Vargas-Rodriguez, Henna Tyynismaa, Claudia Alvarez Carreno, Jiqiang Ling, Lluis Ribas De Pouplana, Xiang-Lei Yang, Multiple Additional Authors Dec 2024

Aars Online: A Collaborative Database On The Structure, Function, And Evolution Of The Aminoacyl-Trna Synthetases, Jordan Douglas, Haissi Cui, John J. Perona, Oscar Vargas-Rodriguez, Henna Tyynismaa, Claudia Alvarez Carreno, Jiqiang Ling, Lluis Ribas De Pouplana, Xiang-Lei Yang, Multiple Additional Authors

Chemistry Faculty Publications and Presentations

The aminoacyl-tRNA synthetases (aaRS) are a large group of enzymes that implement the genetic code in all known biological systems. They attach amino acids to their cognate tRNAs, moonlight in various translational and non-translational activities beyond aminoacylation, and are linked to many genetic disorders. The aaRS have a subtle ontology characterized by structural and functional idiosyncrasies that vary from organism to organism, and protein to protein. Across the tree of life, the 22 coded amino acids are handled by 16 evolutionary families of Class I aaRS and 21 families of Class II aaRS. We introduce AARS Online, an interactive Wikipedia-like …


Investigating The Learning Goals And Expectations Of Laboratory Coordinators, Graduate Teaching Assistants, And Students In General And Organic Chemistry Laboratory Courses, Elizabeth Blanche Vaughan, A. Montoya-Cowan, Christine Kim, Alexandra Stephens, Osie Hamilton, Jack Barbera Nov 2024

Investigating The Learning Goals And Expectations Of Laboratory Coordinators, Graduate Teaching Assistants, And Students In General And Organic Chemistry Laboratory Courses, Elizabeth Blanche Vaughan, A. Montoya-Cowan, Christine Kim, Alexandra Stephens, Osie Hamilton, Jack Barbera

Chemistry Faculty Publications and Presentations

As chemistry education researchers and practitioners continue to investigate and improve undergraduate laboratory courses, it is necessary to consider the perspectives held by each of the stakeholders who are directly involved in these courses, including laboratory coordinators, graduate teaching assistants, and students. This study sought to qualitatively investigate the learning goals and expectations held by laboratory coordinators, graduate teaching assistants (GTAs), and students for general and organic chemistry laboratory courses at a single institution. This was completed through the collection and analysis of semistructured interview data from laboratory coordinators and GTAs and open-ended written responses from students. Results indicated that …


Polymorphism Control Of Polyethylene Terephthalate (Pet) Degradation Product Via Mechanochemistry Leads To Accelerated Microbial Degradation, Deepika Shingwekar, Nicholas Lutz, Delbert S. Botes, Elani J. Cabrera-Vega, Gonzalo Campillo-Alvarado, Jay L. Mellies, Jesus Daniel Loya Nov 2024

Polymorphism Control Of Polyethylene Terephthalate (Pet) Degradation Product Via Mechanochemistry Leads To Accelerated Microbial Degradation, Deepika Shingwekar, Nicholas Lutz, Delbert S. Botes, Elani J. Cabrera-Vega, Gonzalo Campillo-Alvarado, Jay L. Mellies, Jesus Daniel Loya

Chemistry Faculty Publications and Presentations

Here, we optimized a chemo-microbial degradation of polyethylene terephthalate. Developed a path to mechanochemically interconvert between BHET polymorphs and established that BHET polymorphism influences bacterial biodegradation rate.


Investigating Students' Expectations And Engagement In General And Organic Chemistry Laboratory Courses, Elizabeth B. Vaughan, Saraswathi Tummuru, Jack Barbera Oct 2024

Investigating Students' Expectations And Engagement In General And Organic Chemistry Laboratory Courses, Elizabeth B. Vaughan, Saraswathi Tummuru, Jack Barbera

Chemistry Faculty Publications and Presentations

Students’ expectations for their laboratory coursework are theorized to have an impact on their learning experiences and behaviors, such as engagement. Before students’ expectations and engagement can be explored in different types of undergraduate chemistry laboratory courses, appropriate measures of these constructs must be identified, and evidence of validity and reliability for the data collected with these instruments must be investigated. This study collected evidence related to response process validity, internal structure validity, and single administration reliability for version 2 of the Meaningful Learning in the Laboratory Instrument (MLLIv2) and a measure of student engagement in the undergraduate chemistry laboratory. …


Effects Of Spontaneous Curvature On Interfacial Adsorption And Collapse Of Phospholipid Monolayers, Bret A. Brandner, Shankar B. Rananavare, Stephen B. Hall Oct 2024

Effects Of Spontaneous Curvature On Interfacial Adsorption And Collapse Of Phospholipid Monolayers, Bret A. Brandner, Shankar B. Rananavare, Stephen B. Hall

Chemistry Faculty Publications and Presentations

To function effectively, pulmonary surfactant must adsorb rapidly to the alveolar air/water interface but avoid collapse from the surface when compressed to high interfacial densities. Prior studies show that phospholipids in the cylindrical monolayers of the inverse hexagonal (HII) phase adsorb quickly. The monolayers have negative curvature, defined by the concave shape of the hydrophilic face. Formation of the HII structures, however, involves significant disruption of chain-packing. Samples with significant spontaneous curvature, formed in the absence of applied force, may nonetheless have lamellar structures that optimize chain-packing. The experiments here tested whether planar lamellar bilayers formed by phospholipids with negative …