Chemistry Commons^™

Developing Techniques For The Identification Of Non-Canonical Rna Pairing And Analysis Of Lc-Ms Datasets, Christopher Jurich

Department of Chemistry: Dissertations, Theses, and Student Research

Non-canonical pairing dynamics in ribonucleic acid (RNA) structureand statistical analysis of metabolomics liquid chromatography mass spectrometry (LC-MS) datasets are two difficult problems that stand as open challenges.

RNA folding algorithms are used across a variety of disciplines to predict structures when experimental elucidation techniques are inconvenient or impractical. Though successful and widely adopted, folding algorithms make simplifying assumptions for loop regions due to their complex interactions and associated difficulty with generating energy parameters for relevant non-canonical pairing interactions. Modeling assumptions and a lack of energy parameters for loops limit accuracy in these functional critical regions of RNA. This work describes …

Amilorides Inhibit Sars-Cov-2 Replication In Vitro By Targeting Rna Structures, Martina Zafferani, Christina Haddad, Le Luo, Jesse Davila-Calderon, Liang-Yuan Chiu, Christian Shema Mugisha, Adeline G. Monaghan, Andrew A. Kennedy, Joseph D. Yesselman, Robert J. Gifford, Andrew W. Tai, Sebla B. Kutluay, Mei-Ling Li, Gary Brewer, Blanton S. Tolbert, Amanda E. Hargrove

Chemistry Department: Faculty Publications

The SARS-CoV-2 pandemic, and the likelihood of future coronavirus pandemics, emphasized the urgent need for development of novel antivirals. Small-molecule chemical probes offer both to reveal aspects of virus replication and to serve as leads for antiviral therapeutic development. Here, we report on the identification of amiloride-based small molecules that potently inhibit OC43 and SARS-CoV-2 replication through targeting of conserved structured elements within the viral 5′-end. Nuclear magnetic resonance–based structural studies revealed specific amiloride interactions with stem loops containing bulge like structures and were predicted to be strongly bound by the lead amilorides in retrospective docking studies. Amilorides represent the …

Nuscon: A Community-Driven Platform For Quantitative Evaluation Of Nonuniform Sampling In Nmr, Yulia Pustovalova, Frank Delaglio, D. Levi Craft, Haribabu Arthanari, Ad Bax, Martin Billeter, Mark J. Bostock, Hesam Dashti, D. Flemming Hansen, Sven G. Hyberts, Bruce A. Johnson, Krzysztof Kazimierczuk, Hengfa Lu, Mark Maciejewski, Tomas M. Miljenović, Mehdi Mobli, Daniel Nietlispach, Vladislav Orekhov, Robert Powers, Xiaobo Qu, Scott Anthony Robson, David Rovnyak, Gerhard Wagner, Jinfa Ying, Matthew Zambrello, Jeffrey C. Hoch, David L. Donoho, Adam D. Schuyler

Chemistry Department: Faculty Publications

Although the concepts of nonuniform sampling (NUS) and non-Fourier spectral reconstruction in multidimensional NMR began to emerge 4 decades ago (Bodenhausen and Ernst, 1981; Barna and Laue, 1987), it is only relatively recently that NUS has become more commonplace. Advantages of NUS include the ability to tailor experiments to reduce data collection time and to improve spectral quality, whether through detection of closely spaced peaks (i.e., “resolution”) or peaks of weak intensity (i.e., “sensitivity”). Wider adoption of these methods is the result of improvements in computational performance, a growing abundance and flexibility of software, support from NMR spectrometer vendors, and …

Issue Of False Amphetamine Field Test Positives Caused By Sugar. Use Of Baeyer Test As A Secondary Test Solution., Reed A. Knutson, Jennah Duncan, Kara Peightal, Samuel Thomas

Department of Chemistry: Dissertations, Theses, and Student Research

The Marquis reagent is a well-established and widely used chemical presumptive test for 3,4-Methylenedioxymethamphetamine (MDMA) and methamphetamine. It is composed of concentrated sulfuric acid and 40% formaldehyde, which act upon alkaloids causing them to complex into larger molecules. This complexation causes a color change that can be visually interpreted as a positive or negative result. Almost any sugar molecule can be complexed in this way as well, due to their many OH groups. Experimentally it was found that the sugar molecules did complex with one another when the Marquis test was administered. The color produced by this reaction was brownish-red. …

Bioadhesives, Mark Alan Helle, Chin Li Cheung

Chemistry Department: Faculty Publications

Materials and methods for preparing reactive lignin and for preparing a bio - based adhesive are described herein.

Lateral Growth Of Xenon Hydrate Films On Mica, Avinash Kumar Both, Chin Li Cheung

Chemistry Department: Faculty Publications

In this paper, we report an in situ optical microscopy study of lateral growth of xenon (Xe) hydrate thin films on mica at sub-zero temperatures. The interactions between a solid surface and water molecules can strongly affect the alignment of water molecules and induce ice-like ordered structures within the water layer at the water-surface interface. Mica was chosen as a model surface to study the surface effect of hydrophilic sheet silicates on the lateral growth of Xe hydrate films. Under the experimental conditions, the lateral growth of Xe hydrate films was measured to be at an average rapid rate of …

Effects Of Fluoride On Submandibular Glands Of Mice: Changes In Oxidative Biochemistry, Proteomic Profile, And Genotoxicity, Leidiane Alencar De Oliveira Lima, Giza Hellen Nonato Miranda, Walessa Alana Bragança Aragão, Leonardo Oliveira Bittencourt, Sávio Monteiro Dos Santos, Michel Platini Caldas De Souza, Lygia S. Nogueira, Edivaldo Herculano Corrêa De Oliveira, Marta Chagas Monteiro, Aline Dionizio, Aline Lima Leite, Juliano Pelim Pessan, Marília Afonso Rabelo Buzalaf, Rafael Rodrigues Lima

Chemistry Department: Faculty Publications

Although fluoride (F) is well-known to prevent dental caries, changes in cell processes in different tissues have been associated with its excessive exposure. Thus, this study aimed to evaluate the effects of F exposure on biochemical, proteomic, and genotoxic parameters of submandibular glands. Twenty one old rats (n = 30) were allocated into three groups: 60 days administration of drinking water containing 10 mgF/L, 50 mgF/L, or only deionized water (control). The submandibular glands were collected for oxidative biochemistry, protein expression profile, and genotoxic potential analyses. The results showed that both F concentrations increased the levels of thiobarbituric acid–reactive …

Two-Dimensional Monolayer Salt Nanostructures Can Spontaneously Aggregate Rather Than Dissolve In Dilute Aqueous Solutions, Wenhui Zhao, Yunxiang Sun, Weiduo Zhu, Jian Jiang, Xiaorong Zhao, Dongdong Lin, Wenwu Xu, Xiangmei Duan, Joseph S. Francisco, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

It is well known that NaCl salt crystals can easily dissolve in dilute aqueous solutions at room temperature. Herein, we reported the first computational evidence of a novel salt nucleation behavior at room temperature, i.e., the spontaneous formation of two-dimensional (2D) alkali chloride crystalline/non-crystalline nanostructures in dilute aqueous solution under nanoscale confinement. Microsecond-scale classical molecular dynamics (MD) simulations showed that NaCl or LiCl, initially fully dissolved in confined water, can spontaneously nucleate into 2D monolayer nanostructures with either ordered or disordered morphologies. Notably, the NaCl nanostructures exhibited a 2D crystalline square-unit pattern, whereas the LiCl nanostructures adopted non-crystalline 2D hexagonal …

Biomaterials With Structural Hierarchy And Controlled 3d Nanotopography Guide Endogenous Bone Regeneration, Shixuan Chen, Hongjun Wang, Valerio Luca Mainardi, Giuseppe Talò, Alec Mccarthy, Johnson V. John, Matthew J. Teusink, Liu Hong, Jingwei Xie

Chemistry Department: Faculty Publications

Biomaterials without exogenous cells or therapeutic agents often fail to achieve rapid endogenous bone regeneration with high quality. Here, we reported a class of three-dimensional (3D) nanofiber scaffolds with hierarchical structure and controlled alignment for effective endogenous cranial bone regeneration. 3D scaffolds consisting of radially aligned nanofibers guided and promoted the migration of bone marrow stem cells from the surrounding region to the center in vitro. These scaffolds showed the highest new bone volume, surface coverage, and mineral density among the tested groups in vivo. The regenerated bone exhibited a radially aligned fashion, closely recapitulating the scaffold’s architecture. The organic …

Aromatic Substitution: Another View, Charles A. Kingsbury

Chemistry Department: Faculty Publications

Electrophilic substitution on substituted benzenes is reviewed in terms of molecular orbitals. The HOMO falls into two classes. For all meta director C-X groups, a node passes through the ring and through the substituent C-X bond. With ortho/para director C-X groups, a node perpendicular to the one described above, passes through the ortho-meta bonds.

Gate-Tunable Optical Extinction Of Graphene Nanoribbon Nanoclusters, Erin Sheridan, Gang Li, Mamun Sarker, Shan Hao, Ki-Tae Eom, Chang-Beom Eom, Alexander Sinitskii, Patrick Irvin, Jeremy Levy

Chemistry Department: Faculty Publications

We investigate the optical response of graphene nanoribbons (GNRs) using the broadband nonlinear generation and detection capabilities of nanoscale junctions created at the LaAlO₃/SrTiO₃ interface. GNR nanoclusters measured to be as small as 1–2 GNRs in size are deposited on the LaAlO₃ surface with an atomic force microscope tip. Time-resolved nonlinear optical probes of GNR nanoclusters reveal a strong, gate-tunable second and third harmonic response, as well as strong extinction of visible to near-infrared light at distinct wavelengths, similar to previous reports with graphene.

Stem Afterschool Club - Lava Lamps, Dylan Hiser

Honors Expanded Learning Clubs

Afterschool Club that builds upon what students already know about science with fun and interactive experiments.

Harnessing Surface Chemistry And Instabilities In Silicone Elastomers To Synthesize Adaptive Systems With Mechanically Tunable Surface Properties And Functionality, Ali Jamal Mazaltarim

Department of Chemistry: Dissertations, Theses, and Student Research

Material interfaces are of critical importance to numerous fields, including nanomaterials, electronics, microfluidics, synthesis, bioanalysis, pharmaceuticals, and catalysis, and they have been extensively researched. The materials used in these fields are often rigid/hard (such as silicon wafers) resulting in static surface properties. Consequently, the chemical/morphological properties of a surface may be modified using synthetic or mechanical means to tailor the interfacial properties of a material (i.e., surface energy, adhesion, topography, and reactivity). Recently, emphasis has been placed on designing dynamic materials with adaptive interfacial properties that respond to a variety of environmental stimuli. To this end, the surface chemistry and …

Multiple Wetting−Dewetting States Of A Water Droplet On Dual- Scale Hierarchical Structured Surfaces, Yurui Gao, Yuan Liu, Jian Jiang, Chongqin Zhu, Craig Zuhlke, Dennis Alexander, Joseph S. Francisco, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

Surfaces with microscale roughness can entail dualscale hierarchical structures such as the recently reported nano/ microstructured surfaces produced in the laboratory (Wang et al. Nature 2020, 582, 55−57). However, how the dual-scale hierarchical structured surface affects the apparent wetting/ dewetting states of a water droplet, and the transitions between the states are still largely unexplored. Here, we report a systematic large-scale molecular dynamics (MD) simulation study on the wetting/dewetting states of water droplets on various dual-scale nano/near-submicrometer structured surfaces. To this end, we devise slab-water/slab-substrate model systems with a variety of dual-scale surface structures and with different degrees of intrinsic …

Structure Formation And Coupling Reactions Of Hexaphenylbenzene And Its Brominated Analog, Jacob D. Teeter, Paulo S. Costa, Christoph Dobner, Mamun Sarker, Alexander Sinitskii, A Enders

Chemistry Department: Faculty Publications

The on-surface coupling of the prototypical precursor molecule for graphene nanoribbon synthesis, 6,11-dibromo-1,2,3,4-tetraphenyltriphenylene (C₄₂Br₂H₂₆, TPTP), and its non-brominated analog hexaphenylbenzene (C₄₂H₃₀, HPB), was investigated on coinage metal substrates as a function of thermal treatment. For HPB, which forms non-covalent 2D monolayers at room temperature, a thermally induced transition of the monolayer’s structure could be achieved by moderate annealing, which is likely driven by π-bond formation. It is found that the dibrominated carbon positions of TPTP do not guide the coupling if the growth occurs on a substrate at temperatures that …

Surface Functionalization Of Elastomers For Tunable Crystal Growth And Smart Adhesives, John Kapitan

Department of Chemistry: Dissertations, Theses, and Student Research

Silicone rubbers have seen extensive work on modulation of their surface environments for use in microfluidics, cell adhesion, and sensing. Most surface procedures utilize a common initial step of oxidation of the surface to increase the number of active surface functional groups. Following oxidation more permanent functionalities can be imparted on the surface using silanization, grafting polymer brushes, or creating ionic bonds to the surface. Of these three, silanization proves to be the most pervasive due to the range of procedures available and how easy the procedures prove to be. However, the mechanism by which silanization is performed heavily involves …

Bibliometric Analysis Of Named Entity Recognition For Chemoinformatics And Biomedical Information Extraction Of Ovarian Cancer, Vijayshri Khedkar, Charlotte Fernandes, Devshi Desai, Mansi R, Gurunath Chavan Dr, Sonali Tidke Dr., M. Karthikeyan Dr.

Library Philosophy and Practice (e-journal)

With the massive amount of data that has been generated in the form of unstructured text documents, Biomedical Named Entity Recognition (BioNER) is becoming increasingly important in the field of biomedical research. Since currently there does not exist any automatic archiving of the obtained results, a lot of this information remains hidden in the textual details and is not easily accessible for further analysis. Hence, text mining methods and natural language processing techniques are used for the extraction of information from such publications.Named entity recognition, is a subtask that comes under information extraction that focuses on finding and categorizing specific …

Molecular Design Of Three-Dimensional Metal-Free A(Nh4)X3 Perovskites For Photovoltaic Applications, Jie Bie, Dai-Bei Yang, Ming-Gang Ju, Qiang Pan, Yu-Meng You, Wei Fa, Xiao Cheng Zeng, Shuang Chen

Xiao Cheng Zeng Publications

The intense research activities on the hybrid organic−inorganic perovskites (HOIPs) have led to the greatly improved light absorbers for solar cells with high power conversion efficiency (PCE). However, it is still challenging to find an alternative lead-free perovskite to replace the organohalide lead perovskites to achieve high PCE. This is because both previous experimental and theoretical investigations have shown that the Pb²⁺ cations play a dominating role in contributing the desirable frontier electronic bands of the HOIPs for light absorbing. Recent advances in the chemical synthesis of three-dimensional (3D) metal-free perovskites, by replacing Pb²⁺ with NH₄^{+ …}

Effective Microwave-Assisted Approach To 1,2,3-Triazolobenzodiazepinones Via Tandem Ugi Reaction/Catalyst-Free Intramolecular Azide–Alkyne Cycloaddition, Maryna O. Mazur, Oleksii S. Zhelavskyi, Eugene M. Zviagin, Svitlana V. Shishkina, Vladimir I. Musatov, Maksim A. Kolosov, Elena H. Shvets, Anna Yu. Andryushchenko, Valentyn A. Chebanov

Chemistry Department: Faculty Publications

A novel catalyst-free synthetic approach to 1,2,3-triazolobenzodiazepinones has been developed and optimized. The Ugi reaction of 2-azidobenzaldehyde, various amines, isocyanides, and acids followed by microwave-assisted intramolecular azide–alkyne cycloaddition (IAAC) gave a series of target heterocyclic compounds in moderate to excellent yields. Surprisingly, the normally required ruthenium-based catalysts were found to not affect the IAAC, only making isolation of the target compounds harder while the microwave-assisted catalyst-free conditions were effective for both terminal and non-terminal alkynes

Sulfur Anions: Comments Upon Structure, Charles A. Kingsbury

Chemistry Department: Faculty Publications

This work emphasizes the need for solvent simulation as well as a counterion in calculations concerning anions, although optimization may be difficult. Solvent and counterion both play a large role in conformation of the ion. Part of the reason for the success of sulfur anions in chemical reactions may be the ability of sulfone oxygen(s) to coordinate with the counterion (usually lithium). The “solvent” partially dissociates lithium from the carbanion center.

Oxygen Binding Thermodynamics Of Human Hemoglobin In The Red Blood Cell, Kyle K. Hill

Department of Chemistry: Dissertations, Theses, and Student Research

We report for the first time the binding constants and Hill numbers for oxygen in the red blood cell under physiological conditions. When compared to our results for hemoglobin in solution, our results show conclusively that hemoglobin binds oxygen more tightly and with lower co-operativity when packed in the red blood cell. At 18°C, these differences are striking: the respective half-saturation values are 15.57 µM (in red blood cells) and 18.83 µM (in solution), with corresponding Hill numbers of 2.475 (in red blood cells) and 2.949 (in solution). The optical complications that arise from high turbidity of red blood cell …

Identifying Receptors For Neuropeptides And Peptide Hormones: Challenges And Recent Progress, Md Shadman Ridwan Abid, Somayeh Mousavi, James W. Checco

Chemistry Department: Faculty Publications

Intercellular signaling events mediated by neuropeptides and peptide hormones represent important targets for both basic science and drug discovery. For many bioactive peptides, the protein receptors that transmit information across the receiving cell membrane are not known, severely limiting these signaling pathways as potential therapeutic targets. Identifying the receptor(s) for a given peptide of interest is complicated by several factors. Most notably, cell-cell signaling peptides are generated through dynamic biosynthetic pathways, can act on many different families of receptor proteins, and can participate in complex ligand-receptor interactions that extend beyond a simple one-to-one archetype. Here, we discuss recent methodological advances …

Structure Formation And Coupling Reactions Of Hexaphenylbenzene And Its Brominated Analog, Jacob D Teeter, Paulo S. Costa, Christoph Dobner, Mamun Sarker, Alexander Sinitskii, Axel Enders

Chemistry Department: Faculty Publications

The on-surface coupling of the prototypical precursor molecule for graphene nanoribbon synthesis, 6,11-dibromo-1,2,3,4-tetraphenyltriphenylene (C₄₂Br₂H₂₆, TPTP), and its non-brominated analog hexaphenylbenzene (C₄₂H₃₀, HPB), was investigated on coinage metal substrates as a function of thermal treatment. For HPB, which forms non-covalent 2D monolayers at room temperature, a thermally induced transition of the monolayer’s structure could be achieved by moderate annealing, which is likely driven by π-bond formation. It is found that the dibrominated carbon positions of TPTP do not guide the coupling if the growth occurs on a substrate at temperatures that …

Peroxo Species Formed In The Bulk Of Silicate Cathodes, Zhenlian Chen, Bjoern Schwartz, Xianhui Zhang, Wenqiang Du, Lirong Zheng, Ailing Tian, Ying Zhang, Zhiyong Zhang, Xiao Cheng Zeng, Zhifeng Zhang, Liyuan Huai, Jinlei Wu, Helmut Ehrenberg, Deyu Wang, Jun Li

Chemistry Department: Faculty Publications

Oxygen redox in Li-rich oxides may boost the energy density of lithium-ion batteries by incorporating oxygen chemistry in solid cathodes. However, oxygen redox in the bulk usually entangles with voltage hysteresis and oxygen release, resulting in a prolonged controversy in literature on oxygen transformation. Here, we report spectroscopic evidence of peroxo species formed and confined in silicate cathodes amid oxygen redox at high voltage, accompanied by Co2+/Co3+ redox dominant at low voltage. First-principles calculations reveal that localized electrons on dangling oxygen drive the OO dimerization. The covalence between the binding cation and the O-O dimer determines the degree of electron …

Recent Advances In Supramolecular Affinity Separations: Affinity Chromatography And Related Methods, Ashley G. Woolfork, Sazia Iftekhar, Susan Ovbude, Kyungah Suh, Sadia Sharmeen, Isaac Kyei, Jacob Jones, David S. Hage

David Hage Publications

Contents

1 Introduction

2 Supports for Affinity Chromatography

 2.1 Natural Supports and Related Materials

 2.2 Inorganic Supports

 2.3 Synthetic Supports

 2.4 Magnetic Beads and Particles

 2.5 Smart Materials

 2.6 Nanomaterials

 2.7 Support Formats

3 Immobilization Methods

 3.1 Non-Covalent Immobilization

 3.2 Covalent Immobilization

4 Binding Agents Used in Affinity Chromatography

 4.1 Biological Agents as Affinity Ligands

4.1.1 Immunoaffinity Chromatography

4.1.2 Immunoglobulin-Binding Proteins

4.1.3 Lectins

4.1.4 Enzymes

4.1.5 Serum Proteins

4.1.6 Biotin, Avidin, and Streptavidin

4.1.7 Carbohydrates

4.1.8 Lipids

4.1.9 Nucleic Acids

 4.2 Non-Biological Agents as Affinity Ligands

4.2.1 Boronates and Related Mixed Ligands

4.2.2 Dye-Ligands

4.2.3 Immobilized Metal-Ion Chelates

4.2.4 Molecularly …

Dynamic Manipulation Of Droplets Using Mechanically Tunable Microtextured Chemical Gradients, Ali J. Mazaltarim, John J. Bowen, Jay M. Taylor, Stephen Morin

Chemistry Department: Faculty Publications

Materials and strategies applicable to the dynamic transport of microdroplets are relevant to surface fluidics, self-cleaning materials, thermal management systems, and analytical devices. Techniques based on electrowetting, topographic micropatterns, and thermal/chemical gradients have advanced considerably, but dynamic microdroplet transport remains a challenge. This manuscript reports the fabrication of mechano-tunable, microtextured chemical gradients on elastomer films and their use in controlled microdroplet transport. Specifically, discreet mechanical deformations of these films enabled dynamic tuning of the microtextures and thus transport along surface-chemical gradients. The interplay between the driving force of the chemical gradient and the microtopography was characterized, facilitating accurate prediction of …