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Analysis Of Multi-Drug Resistant Mycobacterium Tuberculosis Using Split Deoxyribozymes, Abryana Fergus Jan 2023

Analysis Of Multi-Drug Resistant Mycobacterium Tuberculosis Using Split Deoxyribozymes, Abryana Fergus

Electronic Theses and Dissertations, 2020-2023

Globally, tuberculosis, a disease caused by the species of Mycobacterium tuberculosis (Mtb) complex, stands as a leading cause of death from a single infectious agent. Even though antituberculous drugs are available, treatment is challenging due to antibiotic resistance associated with point mutations in the bacterial genome. Resistance to the first-line antibiotics – rifampin and isoniazid – results in multidrug-resistant tuberculosis (MDR) requiring a more complicated treatment regimen. Timely and accurate identification of drug-resistant TB cases can help prescribe the most effective treatment and prevent the spread of infection. This research aims to develop an assay to discern multi-drug resistant forms …

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A Developmental Investigation Of Separation And Analysis Of Molecular Mass 302 Da Polyaromatic Hydrocarbons Using High Performance Liquid Chromatography And Chiral Stationary Phase, James Janesko Jan 2023

A Developmental Investigation Of Separation And Analysis Of Molecular Mass 302 Da Polyaromatic Hydrocarbons Using High Performance Liquid Chromatography And Chiral Stationary Phase, James Janesko

Electronic Theses and Dissertations, 2020-2023

High molecular weight – polycyclic aromatic hydrocarbons (HMW-PAH) are often found where air, water, and soil are subject to higher levels of industrial pollutants. These molecules are environmentally concerning due to their carcinogenic, mutagenic, and tumorigenic propensities. Furthermore, the isomers in this family are challenging to separate due to similar retention parameters, spectroscopic fingerprints, and mass spectral patterns. The primary purpose of this dissertation is to expand on the methodology for separation and analysis of the molecular mass 302 Da six-ring isomers using High Performance Liquid Chromatography. Retention behaviors of 21 commercially available isomers in synthetic mixture were collected via …

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Functionalizing Metal-Organic Super-Containers (Moscs) For Selective Anion Recognition, Hanying Li Jan 2023

Functionalizing Metal-Organic Super-Containers (Moscs) For Selective Anion Recognition, Hanying Li

Dissertations and Theses

Anions are ubiquitous in Nature and play critical roles in both chemistry and biology. Biologically important molecules like enzymes, DNA, and ATP (adenosine triphosphate) are either anionic or contain negatively charged regions. Inorganic anions such as Cl- and HCO3- play essential roles in various physiological, environmental, and technological processes. Compared to cations, anions have larger ionic radii and more diffuse charge distribution, resulting in weaker electrostatic interactions. Developing synthetic receptors for controlled anion recognition is vital but poses significant challenges. Recent decades have shown remarkable progress in anion recognition, yielding diverse synthetic receptors with promising binding abilities. However, traditional approaches …

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Molecular Biofilm Inhibitors On Noble Metal Surfaces, Mahamadu Tiah Mahama Jan 2023

Molecular Biofilm Inhibitors On Noble Metal Surfaces, Mahamadu Tiah Mahama

Dissertations and Theses

Biofilms are the state microorganisms on surfaces which negatively impact many of processes taking place on them. For example, most microbial infections are attributed to biofilm forma- tion, with bacteria in biofilms exhibiting an antibiotic resistance several orders of magnitude than planktonic bacteria. Therefore, developing antibiofilm agents and understanding their mechanism of inhibition is essential. Citrate functionalized gold nanoparticles are well known for their an- tibiofilm properties. Recently, hybrid bisphosphonate polyoxovanadate gold nanoparticles showed a great potential to inhibit both gram-negative and gram-positive bacteria biofilm formation. How- ever, it is unknown how this species interacts with the metal surface, its …

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Structural And Functional Modulation Of Metal-Organic Supercontainers (Moscs) And Their Applications In Supramolecular Catalysis, Shrijana Dc Jan 2023

Structural And Functional Modulation Of Metal-Organic Supercontainers (Moscs) And Their Applications In Supramolecular Catalysis, Shrijana Dc

Dissertations and Theses

Metal-organic supercontainers (MOSCs), a breakthrough development in our laboratory since 2012, have emerged as promising enzyme mimics, showcasing their prowess in encapsulating guest molecules and catalyzing confined chemical reactions. The intrigue surrounding MOSCs stems from their extraordinary traits, encompassing multiple binding domains, high stability, large surface area, tunable pore size, and structural modularity. Primarily comprising sulfonylcalix[4]arenes, divalent metal ions, and carboxylate linkers, MOSCs' quintessential architecture comprises both endo- and exo- nano-cavities, amenable to guest interaction, with geometry and functionality manipulation achievable through precise precursor selection. Nonetheless, early MOSC models exhibit limited reactivity, often necessitating more potent nucleophiles or electrophiles. This …

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Surface-Engineered Mineral Particles For Gated Drug Delivery, Gene Transfer And Sunscreen Formulations, Mahadi Hasan Jan 2023

Surface-Engineered Mineral Particles For Gated Drug Delivery, Gene Transfer And Sunscreen Formulations, Mahadi Hasan

Dissertations and Theses

Surface-engineered nanomaterials have recently garnered wide attention for their huge biomedical applications. The surface functionalization of nanoparticles by desired chemical groups and coatings imparts unique properties to be used in therapeutic applications. Herein, we reported the biological and biomedical applications of three mineral particles: calcium carbonate nanoparticles, hydroxyapatite nanoparticles and mesoporous silica nanoparticles. The ability of pristine and surface-modified calcium carbonate particles to scatter UV-light significantly depends on the particle’s size, its surface chemical composition, and can be close to the SPF values of commercial sunscreens. These nontoxic particles are a promising component of biocompatible sunscreens free of the traditional …

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Identification Of Rickettsia Prowazekii Methionine Aminopeptidase Inhibitors And Development Of Thermal Shift Assays For Burkholderia Pseudomallei Ispf And Sars-Cov-2 3cl Protease, Ishpriya Sharma Jan 2023

Identification Of Rickettsia Prowazekii Methionine Aminopeptidase Inhibitors And Development Of Thermal Shift Assays For Burkholderia Pseudomallei Ispf And Sars-Cov-2 3cl Protease, Ishpriya Sharma

Graduate Research Theses & Dissertations

There is a crucial need for new antibacterial agents to combat the increase in antibiotic resistance. Methionine aminopeptidase (MetAp) is an enzyme that removes the amino-terminal methionine residue from newly synthesized proteins, an important step in the maturation of proteins. As such, MetAp is a target for the development of antibacterial and anticancer agents. One such bacterial target is Rickettsia prowazekii (Rp), the causative agent of epidemic typhus. To discover new inhibitors of RpMetAp1, the MMV Malaria Box, which is a collection of 400 compounds with drug-like and probe-like compounds, was screened using a high throughput fluorescence-based RpMetAp1 enzyme inhibition …

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Homopurine Guanine-Rich Sequences In Complex With N-Methyl Mesoporphyrin Ix Form Parallel G-Quadruplex Dimers And Display A Unique Symmetry Tetrad, Ming Ye , '23, Erin V. Chen , '23, S. H. Pfeil, Kailey N. Martin, Tamanaa Atrafi , '23, Sara Yun , '23, Zahara Martinez , '23, Liliya A. Yatsunyk Jan 2023

Homopurine Guanine-Rich Sequences In Complex With N-Methyl Mesoporphyrin Ix Form Parallel G-Quadruplex Dimers And Display A Unique Symmetry Tetrad, Ming Ye , '23, Erin V. Chen , '23, S. H. Pfeil, Kailey N. Martin, Tamanaa Atrafi , '23, Sara Yun , '23, Zahara Martinez , '23, Liliya A. Yatsunyk

Chemistry & Biochemistry Faculty Works

DNA can fold into G-quadruplexes (GQs), non-canonical secondary structures formed by π-π stacking of G-tetrads. GQs are important in many biological processes, which makes them promising therapeutic targets. We identified a 42-nucleotide long, purine-only G-rich sequence from human genome, which contains eight G-stretches connected by A and AAAA loops. We divided this sequence into five unique segments, four guanine stretches each, named GA1-5. In order to investigate the role of adenines in GQ structure formation, we performed biophysical and X-ray crystallographic studies of GA1-5 and their complexes with a highly selective GQ ligand, N-methyl mesoporphyrin IX (NMM). Our data indicate …

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Slime Lesson Plans, Admin Stem For Success Jan 2023

Slime Lesson Plans, Admin Stem For Success

STEM for Success Showcase

The STEM for success ambassador program will provide high school students the opportunity to participate in STEM activities that challenge them to learn topics covered in most high school chemistry and physics courses in an environment that cultivates leadership, STEM advocacy, and the 21st century skills of creativity and collaboration. High school students will learn tie-dye science and the chemistry and physics of slime and use their learning experiences to create hands-on activities for Pre-K through 8th grade students. High school students will form teams and venture out into their communities to explore the activities they have created in local …

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Literature Search For Extraction And Characterization Of Fragrant Compounds From Ten Flowering Plants, Ember Smith Jan 2023

Literature Search For Extraction And Characterization Of Fragrant Compounds From Ten Flowering Plants, Ember Smith

All Capstone Projects

This capstone literature project conducted a literature search on the extraction of essential oils from the leaves of ten different flowering plants using steam distillation and/or solvent extraction methods. Additionally, the project focused on characterizing and identifying the fragrant compounds present in the essential oils of these ten plants. By conducting a comprehensive literature search, this project provides a summary of the methods employed for extraction and the composition of fragrant compounds in each essential oil. A diverse range of fragrant compounds were found in various plants and flowers, including major and minor compounds such as alcohols, aldehydes, ketones, terpenes, …

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Structure–Activity Relationship Studies On 6-Chloro-1-Phenylbenzazepines Leads To The Identification Of A New Dopamine D1 Receptor Antagonist, Rajan Giri, Hari K. Namballa, Vishwashiv Emogaje, Wayne W. Harding Jan 2023

Structure–Activity Relationship Studies On 6-Chloro-1-Phenylbenzazepines Leads To The Identification Of A New Dopamine D1 Receptor Antagonist, Rajan Giri, Hari K. Namballa, Vishwashiv Emogaje, Wayne W. Harding

Publications and Research

The 1-phenylbenzazepine template has yielded a number of D1R-like ligands, which, though useful as pharmacological tools, have significant drawbacks in terms of selectivity versus D5R as well as pharmacokinetic behavior. A number of 1-phenylbenzazepines contain a 6-chloro functional group, but extensive SAR studies around the 6-chloro-1-phenylbenzazepine framework have not been reported in the literature. To further understand the tolerance of the 6-chloro-1-phenylbenzazepine template for various substituent groups towards affinity and selectivity at D1R, we synthesized two series of analogs with structural variations at the C-7, C-8, N-3, C-3′ and C-4′ positions. The series 2 analogs differed from …

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Spatial And Temporal Varitations In Dissolved Calcium In The Kentucky Lake Watershed In Relation To Zebra Mussel Colonization, Kelsie Meystedt Jan 2023

Spatial And Temporal Varitations In Dissolved Calcium In The Kentucky Lake Watershed In Relation To Zebra Mussel Colonization, Kelsie Meystedt

Murray State Theses and Dissertations

Calcium is the fifth most abundant element on earth’s crust. Plants and animals require calcium for structure and intracellular metabolism. Recent studies have shown that dissolved calcium (Ca2+) freshwater ecosystems is of growing concern as the increasing concentrations of this element are implicated in altering the natural environment and biota. Elevated levels of dissolved calcium and sporadic re-emergence of an invasive species, namely zebra mussels (Dreissena polymorpha) in Kentucky Lake in the recent years served as a motivation for this study. The objective of this study was to determine spatial and temporal variations in dissolved calcium in selected streams, Kentucky …

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Analysis Of Polycyclic Aromatic Hydrocarbons In Tobacco Related Samples Via High Performance Liquid Chromatography And Laser Excited Time Resolved Shpol' Skii Spectroscopy, Ahmed Comas Jan 2023

Analysis Of Polycyclic Aromatic Hydrocarbons In Tobacco Related Samples Via High Performance Liquid Chromatography And Laser Excited Time Resolved Shpol' Skii Spectroscopy, Ahmed Comas

Electronic Theses and Dissertations, 2020-2023

Human exposure to polycyclic aromatic hydrocarbons (PAHs) due to cigarette smoke is well known. It is also known that PAHs are not inherent components of tobacco. Their presence in cigarette smoke results from the curing process of tobacco leaves used for the fabrication of cigarettes and the incomplete combustion of tobacco during the smoking process. The two chromatographic versions of EPA method 610 are popular approaches for the analysis of PAHs in a wide variety of samples. This method, which is based either on High-Performance Liquid-Chromatography (HPLC) or Gas-Chromatography (GC) has shown the presence of Benzo[a]pyrene (B[a]P) in tobacco samples …

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Mechanism Of Pth Ca2+ Sensing On G-Protein Interactions With Pth1r, Difei Jiang Jan 2023

Mechanism Of Pth Ca2+ Sensing On G-Protein Interactions With Pth1r, Difei Jiang

Lawrence University Honors Projects

Parathyroid hormone 1 receptor (PTH1R) is a family-B GPCR that plays a crucial role in bone remodeling. Previous studies show extracellular Ca2+ is a positive allosteric modulator for one PTH1R ligand, parathyroid hormone (PTH), which is approved by US FDA to treat severe osteoporosis. Moreover, PTH residues E19 & E22 have shown to be involved in Ca2+ sensing. However, the effects of PTH Ca2+ sensing on intracellular G-protein binding are unknown. Here, we used FRET-based SPASM sensors to study the interaction between PTH1R and different Ga peptides. SPASM sensors, which are isolated in native HEK293T membranes through optimized protocol, contain …

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Interactions Of Bioactive Trace Metals In Shipboard Southern Ocean Incubation Experiments, Shannon M. Burns, Randelle M. Bundy, William Abbott, Zuzanna Abdala, Alexa R. Sterling, P. Dreux Chappell, Bethany D. Jenkins, Kristen N. Buck Jan 2023

Interactions Of Bioactive Trace Metals In Shipboard Southern Ocean Incubation Experiments, Shannon M. Burns, Randelle M. Bundy, William Abbott, Zuzanna Abdala, Alexa R. Sterling, P. Dreux Chappell, Bethany D. Jenkins, Kristen N. Buck

OES Faculty Publications

In the Southern Ocean, it is well‐known that iron (Fe) limits phytoplankton growth. Yet, other trace metals can also affect phytoplankton physiology. This study investigated feedbacks between phytoplankton growth and dissolved Fe, manganese (Mn), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), and cadmium (Cd) concentrations in Southern Ocean shipboard incubations. Three experiments were conducted in September–October 2016 near the West Antarctic Peninsula: Incubations 1 and 3 offshore in the Antarctic Circumpolar Current, and Incubation 2 inshore in Bransfield Strait. Additions of Fe and/or vitamin B12 to inshore and offshore waters were employed and allowed assessment of metal (M) …

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Potential Interactions Between Diatoms And Bacteria Are Shaped By Trace Element Gradients In The Southern Ocean, Alexa R. Sterling, Laura Z. Holland, Randelle M. Bundy, Shannon M. Burns, Kristen N. Buck, P. Dreux Chappell, Bethany D. Jenkins Jan 2023

Potential Interactions Between Diatoms And Bacteria Are Shaped By Trace Element Gradients In The Southern Ocean, Alexa R. Sterling, Laura Z. Holland, Randelle M. Bundy, Shannon M. Burns, Kristen N. Buck, P. Dreux Chappell, Bethany D. Jenkins

OES Faculty Publications

The growth of diatoms in the Southern Ocean, especially the region surrounding the West Antarctic Peninsula, is frequently constrained by low dissolved iron and other trace metal concentrations. This challenge may be overcome by mutualisms between diatoms and co-occurring associated bacteria, in which diatoms produce organic carbon as a substrate for bacterial growth, and bacteria produce siderophores, metal-binding ligands that can supply diatoms with metals upon uptake as well as other useful secondary compounds for diatom growth like vitamins. To examine the relationships between diatoms and bacteria in the plankton (diatom) size class (> 3 mu m), we sampled both …

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Atmospheric Input And Seasonal Inventory Of Dissolved Iron In The Sargasso Sea: Implications For Iron Dynamics In Surface Waters Of The Subtropical Ocean, Peter N. Sedwick, Bettina M. Sohst, K. N. Buck, S. Caprara, R. J. Johnson, D. C. Ohnemus, L. E. Sofen, A. Tagliabue, B. S. Twining, Tara E. Williams Jan 2023

Atmospheric Input And Seasonal Inventory Of Dissolved Iron In The Sargasso Sea: Implications For Iron Dynamics In Surface Waters Of The Subtropical Ocean, Peter N. Sedwick, Bettina M. Sohst, K. N. Buck, S. Caprara, R. J. Johnson, D. C. Ohnemus, L. E. Sofen, A. Tagliabue, B. S. Twining, Tara E. Williams

OES Faculty Publications

Constraining the role of dust deposition in regulating the concentration of the essential micronutrient iron in surface ocean waters requires knowledge of the flux of seawater-soluble iron in aerosols and the replacement time of dissolved iron (DFe) in the euphotic zone. Here we estimate these quantities using seasonally resolved DFe data from the Bermuda Atlantic Time-series Study region and weekly-scale measurements of iron in aerosols and rain from Bermuda during 2019. In response to seasonal changes in vertical mixing, primary production and dust deposition, surface DFe concentrations vary from ∼0.2 nM in early spring to >1 nM in late summer, …

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Systemic Analyses Of Radiocarbon Ages Of Coexisting Planktonic Foraminifera, Jörg Lippold, Julia Gottschalk, Jean Lynch-Stieglitz, Matthew W. Schmidt, Sönke Szidat, Andre Bahr Jan 2023

Systemic Analyses Of Radiocarbon Ages Of Coexisting Planktonic Foraminifera, Jörg Lippold, Julia Gottschalk, Jean Lynch-Stieglitz, Matthew W. Schmidt, Sönke Szidat, Andre Bahr

OES Faculty Publications

We compare radiocarbon (14C) ages of coexisting planktonic foraminifera species from sediment cores VM12-107 and KNR166-2-26JPC from the Equatorial Atlantic Ocean for three time periods (Holocene, Heinrich Stadial 1, last glacial maximum). We find a maximum inter-species difference of 1200 14C yr. On average, the 14C ages deviate by ∼300 yr between Globigerinoides ruber and other species. In most cases, this exceeds the analytical uncertainty range of the measurements and thus renders the choice of species for generating age models as important as sample weight. While modern stratified water-column profiles imply an increase in 14C …

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Global Oceanic Diazotroph Database Version 2 And Elevated Estimate Of Global N2 Fixation, Zhibo Shao, Yangchun Xu, Hua Wang, Weicheng Luo, Lice Wang, Yuhong Huang, Nona Sheila R. Agawin, Ayaz Ahmed, Mar Benavides, Mikkel Bentzon-Tilia, Ilana Berman-Frank, Hugo Berthelot, Isabelle C. Biegala, Mariana B. Bif, Antonio Bode, Sophie Bonnet, Deborah A. Bronk, Mark V. Brown, Lisa Campbell, Ya-Wei Luo Jan 2023

Global Oceanic Diazotroph Database Version 2 And Elevated Estimate Of Global N2 Fixation, Zhibo Shao, Yangchun Xu, Hua Wang, Weicheng Luo, Lice Wang, Yuhong Huang, Nona Sheila R. Agawin, Ayaz Ahmed, Mar Benavides, Mikkel Bentzon-Tilia, Ilana Berman-Frank, Hugo Berthelot, Isabelle C. Biegala, Mariana B. Bif, Antonio Bode, Sophie Bonnet, Deborah A. Bronk, Mark V. Brown, Lisa Campbell, Ya-Wei Luo

OES Faculty Publications

Marine diazotrophs convert dinitrogen (N2) gas into bioavailable nitrogen (N), supporting life in the global ocean. In 2012, the first version of the global oceanic diazotroph database (version 1) was published. Here, we present an updated version of the database (version 2), significantly increasing the number of in situ diazotrophic measurements from 13 565 to 55 286. Data points for N2 fixation rates, diazotrophic cell abundance, and nifH gene copy abundance have increased by 184 %, 86 %, and 809 %, respectively. Version 2 includes two new data sheets for the nifH gene copy abundance of non-cyanobacterial …

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Isotopic Evidence For Sources Of Dissolved Carbon And The Role Of Organic Matter Respiration In The Fraser River Basin, Canada, Britta M. Voss, Timothy I. Eglinton, Bernhard Peucker-Ehrenbrink, Valier Galy, Susan Q. Lang, Cameron Mcintyre, Robert G.M. Spencer, Ekaterina Bulygina, Zhaohui Aleck Wang, Katherine A. Guay Jan 2023

Isotopic Evidence For Sources Of Dissolved Carbon And The Role Of Organic Matter Respiration In The Fraser River Basin, Canada, Britta M. Voss, Timothy I. Eglinton, Bernhard Peucker-Ehrenbrink, Valier Galy, Susan Q. Lang, Cameron Mcintyre, Robert G.M. Spencer, Ekaterina Bulygina, Zhaohui Aleck Wang, Katherine A. Guay

OES Faculty Publications

Sources of dissolved and particulate carbon to the Fraser River system vary significantly in space and time. Tributaries in the northern interior of the basin consistently deliver higher concentrations of dissolved organic carbon (DOC) to the main stem than other tributaries. Based on samples collected near the Fraser River mouth throughout 2013, the radiocarbon age of DOC exported from the Fraser River does not change significantly across seasons despite a spike in DOC concentration during the freshet, suggesting modulation of heterogeneous upstream chemical and isotopic signals during transit through the river basin. Dissolved inorganic carbon (DIC) concentrations are highest in …

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การเตรียมและลักษณะเฉพาะของแวกซ์เอสเทอร์จากกรดปาลมิติก, ณัฐกมล ดีมูลมั่ง Jan 2023

การเตรียมและลักษณะเฉพาะของแวกซ์เอสเทอร์จากกรดปาลมิติก, ณัฐกมล ดีมูลมั่ง

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้มุ่งเน้นการสังเคราะห์แวกซ์ปาลมิติกผ่านปฏิกิริยารีดักชันและปฏิกิริยาเอสเทอริฟิเคชัน ปฏิกิริยารีดักชันเป็นการเปลี่ยนกรดปาลมิติกเป็นปาลมิติกแอลกอฮอล์ ตัวแปรของการศึกษานี้คือปริมาณของตัวเร่งปฏิกิริยาและเวลา ภาวะที่เหมาะสมในการทำปฏิกิริยาคือ ปริมาณของตัวเร่งปฏิกิริยา 2.66%w/w และเวลา 24 ชั่วโมง เนื่องจากผลิตภัณฑ์ที่ได้เป็นของผสมระหว่างผลิตภัณฑ์ปาลมิติกแอลกอฮอล์และกรดปาลมิติกส่วนเกิน จึงมีการสกัดแยกด้วยตัวทำละลาย เช่น เมทานอล เอทานอล ไอโซ-โพรพานอล เมทิลเอทิลคีโตน และไดเมทิลฟอร์มาไมด์ เพื่อแยกกรดปาลมิติกและผลิตภัณฑ์ปาลมิติกแอลกอฮอล์ จากนั้นทำปฏิกิริยาเอสเทอริฟิเคชันเพื่อสังเคราะห์แวกซ์เอสเทอร์ที่ได้จากกรดปาลมิติกและปาลมิติกแอลกอฮอล์ พบว่าแวกซ์ปาลมิติกสังเคราะห์จากปาลมิติกแอลกอฮอล์ได้สำเร็จ (อัตราส่วนระหว่าง CA/ตัวทำละลายเป็น 1:2) คือ W-CA-MeOH2, W-CA-EtOH2 และ W-CA-MEK2 ให้ร้อยละผลได้ของแวกซ์ปาลมิติกเอสเทอร์สูงที่ 48.1, 71.0 และ 56.7% ตามลำดับ สมบัติทางกายภาพและทางเคมีของแวกซ์ปาลมิติกศึกษาด้วยการวิเคราะห์ FTIR, XRD, NMR, DSC และ TGA แวกซ์ปาลมิติก W-CA-EtOH2 ซึ่งเป็นสารเคลือบกระดาษมีค่าความไม่ชอบน้ำยิ่งยวดสูงด้วยค่ามุมสัมผัส 161.4 องศา นอกจากนี้การเคลือบ W-CA-EtOH2 มีความต้านทานน้ำสูงโดยมีการดูดซึมน้ำต่ำที่ 0.43 ผลของการศึกษานี้บ่งบอกกระดาษที่เคลือบด้วยแวกซ์ปาลมิติกมีประสิทธิภาพความทนน้ำเพิ่มขึ้นเมื่อเทียบกับกระดาษที่ไม่คลือบ

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Extracting High-Molecular Weight Dna From Cyanobacteria Using Promega's Wizard® Hmw Dna Extraction Kit With A Modified Protocol, Metis, Megan A. Hept, Lesley H. Greene Jan 2023

Extracting High-Molecular Weight Dna From Cyanobacteria Using Promega's Wizard® Hmw Dna Extraction Kit With A Modified Protocol, Metis, Megan A. Hept, Lesley H. Greene

Chemistry & Biochemistry Faculty Publications

Extraction of high molecular weight (HMW) DNA for long read sequencing with little to no fragmentation and high purity is difficult to acquire from cyanobacterial species. Here we describe a modified method of extraction using Promega's Wizard® HMW DNA Extraction Kit to acquire high molecular weight DNA from cyanobacterial species. The protocol used in the kit is the “3.D. Isolating HMW DNA from Gram-Positive and Gram-Negative Bacteria” protocol. During a key step in the protocol, the lingering remnants of the mucilage layer of the cyanobacterial species is removed, preventing it from sticking to the DNA pellet produced. This customized modification …

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Design, Synthesis, And Enzyme Inhibition Evaluation Of Some Novel Mono- And Di-O-Ss-D-Glycopyranosyl Chalcone Analogues With Molecular Docking Studies, Gonca Çeli̇k, Gi̇zem Tatar Yilmaz, Hüseyi̇n Şahi̇n, Burak Barut, Nuretti̇n Yayli Jan 2023

Design, Synthesis, And Enzyme Inhibition Evaluation Of Some Novel Mono- And Di-O-Ss-D-Glycopyranosyl Chalcone Analogues With Molecular Docking Studies, Gonca Çeli̇k, Gi̇zem Tatar Yilmaz, Hüseyi̇n Şahi̇n, Burak Barut, Nuretti̇n Yayli

Turkish Journal of Chemistry

In this study, some novel mono- and di-O-β-D-glycopyranosyl chalcone analogs were designed, synthesized, and characterized. The chalcone derivatives were synthesized with good yields by base-catalyzed Claisen-Schmidt condensation in EtOH solution. Then these chalcones were reacted with TAGBr (2,3,4,6-tetra-O-acetyl-μ-D-glucopyranosylbromide) in dry acetone under the anhydrous condition at 0-5 °C. Deacylated was carried out by the Zemplen's method with NaOCH3 in dry methanol results in substituted chalcone-O-glycosides (mono- and di-O-β-D-glycopyranosyl chalcone analogs). The chemical structures of all synthesized compounds were elucidated based on IR, NMR spectral data, and mass spectrometry. Further, the compounds (7a-c, 8a-c, 12a-c, 16a-c, and 17a-c) …

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Effect Of Microfluidic Channel Integration Onto Gold Microelectrode On Its Redox Electrochemistry, Ahmet Uçar, Zahraa Ali Hajool, Hamed Ghorbanpoor, Reza Didarian, Fatma Doğan Güzel Jan 2023

Effect Of Microfluidic Channel Integration Onto Gold Microelectrode On Its Redox Electrochemistry, Ahmet Uçar, Zahraa Ali Hajool, Hamed Ghorbanpoor, Reza Didarian, Fatma Doğan Güzel

Turkish Journal of Chemistry

Microfluidic systems have attracted significant interest in recent years as they are extensively employed in lab-on-chip and organ-on-chip research. Their combination with electrochemical platforms offers many advantages, promising a high potential for sensing applications, still the microfluidic-channel integration onto electrodes might induce challenges related to changes in signal-tonoise ratios and mass transport conditions. In this study, we investigated the effect of microfluidic channel integration in redox behavior of thermally deposited gold thin film microelectrodes by voltammetric (CV and SWV) electrochemical measurements. Using different dimensions of PDMS microfluidic channels (i.e. widths of 50, 100, 250, and 500 μm) and a constant …

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Privileged Fragment-Based Design, Synthesis And In Vitro Antitumor Activity Of Imatinib Analogues, Hongyu Jiang, Yuankun Wang, Maokai Jiang, Lei Yao Jan 2023

Privileged Fragment-Based Design, Synthesis And In Vitro Antitumor Activity Of Imatinib Analogues, Hongyu Jiang, Yuankun Wang, Maokai Jiang, Lei Yao

Turkish Journal of Chemistry

Based on the privileged fragment-based drug design strategy, a series of imatinib analogues bearing the moiety of 3-(2-amino- 2-oxoacetyl)-1H-indole were designed and synthesized, and the in vitro antitumor activity of these compounds was detected by MTT method using K562 (human myeloid leukemia) and K562R (imatinib-resistant chronic myeloid leukemia) cell lines. Molecular docking was used to preliminarily explain the possible binding modes. The most potent compound I2 exhibited better antitumor activity than those of imatinib against K562 and K562R cancer cells with IC50 values of 0.8 ?M and 0.7 ?M.

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Ultrasound-Assisted Synthesis Of Rgo/Sio2-Based Nanosheets And Their Electrochemical Performances In Li-Ion Batteries, Ersu Lökçü, Süleyman Can, Mustafa Anik Jan 2023

Ultrasound-Assisted Synthesis Of Rgo/Sio2-Based Nanosheets And Their Electrochemical Performances In Li-Ion Batteries, Ersu Lökçü, Süleyman Can, Mustafa Anik

Turkish Journal of Chemistry

In this study, a facile approach has been developed to fabricate GO/SiO2 nanosheets by the hydrolysis of tetraethyl orthosilicate (TEOS) in the graphene oxide (GO) solution with the assistance of the ultrasonication. The morphology and structure of the SiO2/GO nanosheets were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) and Raman spectroscopy. The results showed that the covalently bonded SiO2 nanoparticles onto the GO sheets were dense and uniform. The agglomeration of the nanosheets was prevented by the ultrasonication and the layer sizes decreased throughout the synthesis process. The size and thickness of the SiO2 …

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Carbon Nanotube/Waterborne Polyurethane Nanocomposites With Light-To-Heat Conversion Properties, Hayri̇ye Ünal Jan 2023

Carbon Nanotube/Waterborne Polyurethane Nanocomposites With Light-To-Heat Conversion Properties, Hayri̇ye Ünal

Turkish Journal of Chemistry

Photothermal materials and coatings which can create temperature elevations under light irradiation can be utilized in various applications requiring remote heating. Here, multiwalled carbon nanotubes (MWNT) were incorporated into waterborne polyurethane (PU) to obtain photothermal coatings with light-to-heat conversion properties. Resulting PU-MWNT coatings were demonstrated to heat up to 80 °C under sunlight irradiation at 2 sunlight density for 18 min. Pseudomonas aeruginosa (P. aeruginosa) cells attached to surfaces coated with PU-MWNT nanocomposites were killed upon near infrared (NIR) light irradiation at 808 nm for 15 min, whereas the same cells attached to control neat PU-coated surfaces remained alive under …

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Spectrophotometric Quantification Of Paracetamol And Tramadol Hydrochloride By Chemometric Calibration Methods, Faysal Seli̇moğlu, Nermi̇n Pinarcik Jan 2023

Spectrophotometric Quantification Of Paracetamol And Tramadol Hydrochloride By Chemometric Calibration Methods, Faysal Seli̇moğlu, Nermi̇n Pinarcik

Turkish Journal of Chemistry

The results of UV spectrophotometric analysis were analysed using partial least squares (PLS) and principal component regression (PCR) techniques to allow simultaneous evaluation of tramadol hydrochloride (TRA) and p-acetaminophen (PAR) in tablets. A calibration set of 16 mixtures, each containing PAR and TRA in various amounts, was created using a 24-full fractional design. The absorbance data set for the calibration set were obtained between 215?280 nm (?? = 0.1 nm). Subsequently, the concentration and absorbance sets were used to generate PCR and PLS calibrations. The ratio spectra- first derivative method was devised as a solution to the same problem to …

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Development And Biological Evaluation Of Selective Small-Molecule Inhibitors Of The Human Cytochrome P450 1b1, Austin Hachey Jan 2023

Development And Biological Evaluation Of Selective Small-Molecule Inhibitors Of The Human Cytochrome P450 1b1, Austin Hachey

Theses and Dissertations--Chemistry

The human cytochrome P450 1B1 (CYP1B1) is an emerging target for small- molecule therapeutics. Several solid tumors overexpress CYP1B1 to the degree that it has been referred to as a universal tumor antigen. Conversely, its expression is low in healthy tissues. CYP1B1 may drive tumorigenesis through promoting the formation of reactive toxins from environmental pollutants or from endogenous hormone substrates. Additionally, the expression of CYP1B1 in tumors is associated with resistance to several common chemotherapies and with poor prognoses in cancer patients. However, inhibiting CYP1B1 with small molecules has been demonstrated in cellular and murine model systems to reverse this …

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Advances In Bioelectrode Design For Developing Electrochemical Biosensors, Nabajyoti Kalita, Sudarshan Gogoi, Shelley D. Minteer, Pranab Goswami Jan 2023

Advances In Bioelectrode Design For Developing Electrochemical Biosensors, Nabajyoti Kalita, Sudarshan Gogoi, Shelley D. Minteer, Pranab Goswami

Chemistry Faculty Research & Creative Works

The critical performance factors such as selectivity, sensitivity, operational and storage stability, and response time of electrochemical biosensors are governed mainly by the function of their key component, the bioelectrode. Suitable design and fabrication strategies of the bioelectrode interface are essential for realizing the requisite performance of the biosensors for their practical utility. A multifaceted attempt to achieve this goal is visible from the vast literature exploring effective strategies for preparing, immobilizing, and stabilizing biorecognition elements on the electrode surface and efficient transduction of biochemical signals into electrical ones (i.e., current, voltage, and impedance) through the bioelectrode interface with the …

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