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Synthesis Of Pyridinium-Based Ionic Liquids And Their Application To Improve Candida Rugosa Lipase Stability In A Methanol-Water Solvent System, Oktavianus Cipta, Anita Alni, Rukman Hertadi

Turkish Journal of Chemistry

This paper studied the effect of pyridinium-based ionic liquids as cosolvents in a methanol-water solvent system on the hydrolytic activity of Candida rugosa lipase. These ionic liquids were successfully synthesized using imidazolium-based ionic liquid synthesizing methods with a certain adjustment. The hydrolytic activity of Candida rugosa lipase was analyzed using 4-nitrophenol acetate (pNPA) and 4-nitrophenol palmitate (pNPP) as substrates. The addition of ionic liquids had no significant effect on the hydrolytic activity of lipase in a water solvent, and it had a greater effect in methanol. The addition of [C6Py] Br ionic liquid as a methanol cosolvent (methanol: ionic liquid, …

Surfactant Incorporated Preyssler Polyoxoanion: A Transition Metal Substituted Mo-Php Complex And Its Applications, Bharath Samannan, Jothi Selvam, Yi-Li Lin, Praveen Peter, Jeyabalan Thavasikani

Turkish Journal of Chemistry

The complex was prepared with preyssler polyoxoanion and transition metal (Mo), a cationic surfactant as a connector. It has tuneable physical and chemical potential which has been exploited to study novel properties. A new technique of shock wave impulses is also used on the Mo-PHP complex. Extensive use of cationic surfactants could impact accumulation in the environment set off the surfacing of bacterial resistance. Due to the electrostatic binding to bacterial surface, the hydrophobic parts of cationic surfactants tend to penetrate bacterial cell walls and may cause membrane lysis and bacteria death. The surfactant-supported and direct release of metal ions …

Additive-Free Synthesis Of Poly(N-Vinyl Pyrrolidone) And Poly(N-Isopropylacrylamide) Nanogels With Controlled Sizes, Semi̇ha Duygu Süteki̇n, Feyza Kiraç, Olgun Güven

Turkish Journal of Chemistry

An easy method is proposed to prepare poly(vinyl pyrrolidone) (PVP) and poly(N-isopropylacrylamide) (PNiPAAm) nanogels with sizes less than 100 nm. The underlying principle is to prepare dilute polymer solutions in acetone/water mixtures where acetone acts to break tridimensional structure of water hence disrupting the H-bonds bridging polymer coils causing separation and shrinkage in their sizes. Irradiation of these solutions by gamma-rays directly leads to the formation of intramolecular crosslinks within the coils resulting with nanogels with sizes smaller than precursor coils. While the average size of nanogels of PVP irradiated in water only is 236 nm, they were reduced to …

Ultraviolet-Activated Clamshell Hydroxyapatite-Substituted Palladium In The Photoreduction Of Methyl Orange Water Pollutant, Anis Liyana Azhar, Azman Ma'amor, Nurhidayatullaili Muhd Julkapli, Nor Asrina Sairi, Aina Sofea Noraizat

Turkish Journal of Chemistry

This study focuses on the modification of natural hydroxyapatite (HAp) derived from clamshell by impregnation with palladium (Pd) at different pH in wet precipitation method to produce photoactive green materials for the degradation of synthetic dyes. It was found that, at pH 10, Pd has been successfully impregnated into HAp lattice with Ca/P ratio of 1.77 and particle distribution size range of 40?470 nm. The impregnation has resulted in the band gap of Pd/HAp at 3.19 eV, as calculated using Tauc?s plot from the UV-Vis spectroscopy data of the Pd/HAp. Next, the photocatalytic activities of Pd/HAp were carried out with …

Molecular Dynamics Modeling Of Polymers For Aerospace Composites, Swapnil Sambhaji Bamane

Dissertations, Master's Theses and Master's Reports

Polymer matrix composite materials are widely used as structural materials in aerospace and aeronautical vehicles. Resin/reinforcement wetting and the effect of polymerization on the thermo-mechanical properties of the resin are key parameters in the manufacturing of aerospace composite materials. Determining the contact angle between combinations of liquid resin and reinforcement surfaces is a common method for quantifying wettability. It is challenging to determine contact angle values experimentally of high-performance resins on CNT materials such as CNT, graphene, bundles or yarns, and BNNT surfaces. It is also experimentally difficult to determine the effect of polymerization reaction on material properties of a …

Multilevel Computational Investigation Into The Catalytic Mechanisms Of Matrix Metalloproteinase-1 And Fat Mass And Obesity-Associated Enzyme, Ann Varghese

Dissertations, Master's Theses and Master's Reports

Enzymes are biological macromolecules, typically proteins, that efficiently accelerate the rate of chemical reactions. Their remarkable catalytic power plays a vital role in essential processes across all kingdoms of life. Nowadays, computational chemistry methods provide valuable insights into enzymatic functions aiding our understanding of biological processes and providing advancements in fields such as biomedical sciences, biomimetic catalysis, drug design and biotechnology. This dissertation employs multilevel computational chemistry methods to investigate the structure-function relationships and the catalytic mechanisms of two metalloenzymes -Zn(II)-dependent matrix metalloproteinase-1 (MMP-1) and non-heme Fe(II)/2-oxoglutarate (2OG) dependent fat-mass and obesity-associated (FTO) enzyme. Chapter 2 explores the role of …

Multiscale Molecular Modeling Studies Of The Dynamics And Catalytic Mechanisms Of Iron(Ii)- And Zinc(Ii)-Dependent Metalloenzymes, Sodiq O. Waheed

Dissertations, Master's Theses and Master's Reports

Enzymes are biological systems that aid in specific biochemical reactions. They lower the reaction barrier, thus speeding up the reaction rate. A detailed knowledge of enzymes will not be achievable without computational modeling as it offers insight into atomistic details and catalytic species, which are crucial to designing enzyme-specific inhibitors and impossible to gain experimentally. This dissertation employs advanced multiscale computational approaches to study the dynamics and reaction mechanisms of non-heme Fe(II) and 2-oxoglutarate (2OG) dependent oxygenases, including AlkB, AlkBH2, TET2, and KDM4E, involved in DNA and histone demethylation. It also focuses on Zn(II) dependent matrix metalloproteinase-1 (MMP-1), which helps …

Chemical Decomposition Of Flexible Polyurethane Foam To Generate A Media For Microbial Upcycling, Kaushik Baruah

Dissertations, Master's Theses and Master's Reports

Polyurethane waste is becoming a global concern as a large amount is being disposed of in landfills every year, and only a fraction is being recycled. Several polyurethane recycling techniques exist, of which ammonolysis and base-catalyzed hydrolysis is the least explored. Flexible polyurethane foam (FPUF) decomposition can generate amines that can act as a carbon source for the growth of microbial consortia. This study aims to generate a novel media capable of microbial upcycling via ammonolysis and base-catalyzed hydrolysis of flexible polyurethane foams (FPUFs) using ammonium hydroxide and subsequently determine the reaction conditions for maximum solubilization of polyurethane foam in …

Investigation Of Unexpected Purple Substance Extracted From Newsprint Paper, Raquel Wilhelm

Honors Program Theses

In an attempt to extract a green dye from newsprint advertisements, it was serendipitously discovered that a purple substance can be extracted from newsprint paper using methanol or acetic acid.1 Further investigations involving blank newsprint paper showed that the purple substance was a part of the paper itself rather than a component of the ink in the advertisements. Soxhlet extraction was used on the blank newspaper print to obtain the compound. Using different analytical instruments, characteristics of the compound were determined such as potential structures, functional groups, and percent composition. The ultimate goal was to determine the compound and its …

Triplet Sensitization Enables Bidirectional Isomerization Of Diazocine With 130 Nm Redshift In Excitation Wavelengths, Jussi Isokuortti, Thomas Griebenow, Jan-Simon Von Glasenapp, Tim Raeker, Timo Laaksonen, Rainer Herges, Nikita A. Durandin

Articles

Diazocines are bridged azobenzenes with phenyl rings connected by a CH2–CH2 group. Despite this rather small structural difference, diazocine exhibits improved properties over azobenzene as a photoswitch and most importantly, its Z configuration is more stable than the E isomer. Herein, we reveal yet another unique feature of this emerging class of photoswitches. In striking contrast to azobenzenes and other photochromes, diazocine can be selectively switched in E / Z direction and most intriguingly from its thermodynamically stable Z to metastable E isomer upon successive excitation of two different triplet sensitizers present in solution at the same time. This approach …

The Biological Responses Of Vitamin K2: A Comprehensive Review, Quanxiang Yan, Tao Zhang, Christine O'Connor, James W. Barlow, John Walsh, Gaia Scalabrino, Feng Xu, Helan Sheridan

Articles

Vitamin K1 (VitK1) and Vitamin K2 (VitK2), two important naturally occurring micronutrients in the VitK family, found, respectively, in green leafy plants and algae (VitK1) and animal and fermented foods (VitK2). The present review explores the multiple biological functions of VitK2 from recently published in vitro and in vivo studies, including promotion of osteogenesis, prevention of calcification, relief of menopausal symptoms, enhancement of mitochondrial energy release, hepato-and neuro-protective effects, and possible use in treatment of coronavirus disease. The mechanisms of action associated with these biological effects are also explored. Overall, the findings presented here suggest that VitK, especially VitK2, is …

Synthesis, Molecular Simulation Studies, In Vitro Biological Assessment Of 2-Substituted Benzoxazole Derivatives As Promising Antimicrobial Agents, Gajanan S. Shanbhan, Amit Bhargava, Giridhar Pal Singh, Shrinivas D. Joshi, Narendra Chundawat

Turkish Journal of Chemistry

The 2-substituted benzoxazole derivatives are known to exhibit a wide spectrum of biological potential. Two series of novel benzoxazole derivatives containing 2-phenyl and 2-N-phenyl groups were synthesized, by following the green chemistry approach. All the newly synthesized derivatives were screened against gram-positive bacteria (Streptococcus pyogenes, Staphylococcus aureus), gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli) and the fungus (Aspergillus clavatus and Candida albicans). Most of these compounds have demonstrated potent antibacterial activities, especially against E. coli at 25 μg/mL, along with moderate antifungal activity. Among these, two compounds, 21 and 18, showed interesting antibacterial profile. Molecular …

Investigating Visinin-Like Protein 1 And Ubiquitinated Visinin-Like Protein 1 As Mild Traumatic Brain Injury Biomarkers, Yueming Wu

Theses and Dissertations--Chemistry

Traumatic brain injury (TBI) continues to be a significant cause of morbidity and mortality worldwide. Despite significant progress in understanding the complex pathophysiology of TBI, the underlying mechanisms remain poorly understood. The primary brain damage is acute and irreversible. However, secondary brain injuries often develop gradually over months to years, creating an opportunity for critical therapeutic interventions. In the past decade, research on TBI biomarkers has seen significant progress. This progress has been driven by the diverse nature of TBI pathologies and the challenges they present for evaluation, management, and prognosis. TBI biomarker proteins resulting from axonal, neuronal, or glial …

College Of Natural Sciences 2022 Year-End Publication, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

This is the 2022 issue of the annual College of Natural Sciences year-end publication.

Contents:
[Page] 2 Dean's message
[Page] 3 Department highlights
[Page] 4 Overview of Bold & Blue Campaign
[Page] 5 Dr. Edward Hogan recognition & endowment
[Page] 6 Career milestones
[Page] 7 Student travel and research
[Page] 8 $11 million COBRE grant
[Page] 9 Professional Science Masters & Research highlights
[Page]10 Outreach highlights throughout the state
[Page] 11 2022 events recap – join us in 2023!
[Page] 12 Updates on our VR initiative
[Page] 14 Overview of awards and recognitions from 2022

One-Pot Enol Silane Formation-Allylation Of Ketones Promoted By Trimethylsilyl Trifluoromethanesulfonate, Elizabeth D. Heafner, Xuechun Lin, Alexa Connors, Hanyu Zhong, R. J. Coyle, Yiqi Liu, C. Wade Downey

Chemistry Faculty Publications

Ketones and related substrate classes undergo enol silane formation in the presence of trimethylsilyl trifluoromethanesulfonate (TMSOTf) and triethylamine, reaction conditions that also promote the in situ ionization of allyl propionates. When these two processes are performed in one pot, allylation of the ketone is observed in high yields. Aldehydes, esters, and thioesters also serve as enol silane precursors under these conditions. When unsymmetrical allyl cations are employed, regioselectivity depends upon the electronic and steric properties of the substituents.

Organic Chemistry Ii, Layne Morsch, Steven Farmer, Krista Cunningham, Zachery Sharrett, Kevin M. Shea

Open Educational Resources: Textbooks

This text has many contributors. It was adapted for use in CHM 223 at Smith College by Kevin Shea with the assistance of a Smith College Library OER Incentive Grant.

Exogenous Factors That Impact Huntingtin Aggregation, Adam Skeens

Graduate Theses, Dissertations, and Problem Reports (ETD)

While expansion of a polyglutamine (polyQ) domain is the immediate cause of huntingtin (htt) aggregation associated with Huntington’s Disease (HD), other cellular factors modify aggregation. These include interactions with cellular membranes, protein biding partners, molecular crowding, and proteinaceous seeds. Here, two important factors are biophysically characterized: 1) the interaction of htt with endomembranes and 2) proteinaceous seeds obtained from a variety of htt-derived peptides. In the first project, the aggregation of htt at bilayer interfaces and in the presence of divalent cations was investigated. A major cellular factor implicated in altered htt aggregation is the binding of lipids. Furthermore, the …

3d Printed Microfluidic Devices For Advanced Fluid Manipulation In Biomedical Applications, Kathrine Curtin

Graduate Theses, Dissertations, and Problem Reports (ETD)

Microfluidics are valuable devices in the biomedical field because of their remarkable ability to manipulate small volumes of fluid and facilitate reactions. Microfluidics have several significant advantages, including their portability, low cost, fast reaction times, and high surface area-to-volume ratios. Microfluidics be used for a multitude of applications, including bioanalysis, cellular assays, organ-on-a-chip, and separations. Microfluidics have great potential to overcome many challenges in conventional chemical and biological applications. However, complex fabrication procedures in silicon, glass, thermoplastics, and (polydimethylsiloxane) PDMS devices make rapidly optimizing and prototyping devices challenging. Microfluidic fabrication techniques have been a long-standing challenge in successfully translating these …

Developing New Ionization Strategies For Characterizing Structural Flexibility, Heterogeneity, And Transformation Of Biopolymers, Daud Sharif

Graduate Theses, Dissertations, and Problem Reports (ETD)

Biopolymers, such as proteins and nucleic acids, serve important functions dictated by their structural folding. Information excavated from the intricate structural arrangements of biopolymers have been proved to be vital in diagnosing diseases, unveiling disease mechanisms, and developing new drugs. A continuous effort has been put to improve the characterization techniques of these biomolecules so that more precision can be achieved in terms of detailing their structure-function relationship. Mass spectrometry (MS) is one such technique that has become very relevant for structural biology with the emergence of soft ionization techniques such as electrospray ionization (ESI). A prerequisite to the application …

Analysis Of ‘Touch’ Dna Recovered From Metal Substrates: An Investigation Into Cfdna-Metal Interactions And The Efficacy Of Different Collection Techniques On Dna Yield, Jessica E. Thornton

Graduate Theses, Dissertations, and Problem Reports (ETD)

While several improvements have been made in recent years to optimize the recovery of ‘touch’ DNA, relatively little research has been conducted to understand the relationship between ‘touch’ DNA and the binding affinity of that DNA to metal surfaces, specifically those with a significant copper presence. Furthermore, characterization of cell-free DNA (cfDNA) and its contribution to ‘touch’ samples and those cfDNA-metal interactions from objects commonly identified at crime scenes (cartridge casings, knives, doorknobs) have been lacking. Research has identified the tendency of copper ions to intercalate with DNA helices, resulting in sample degradation among other damaging conformational changes; however, while …

Noncovalent Chalcogen And Tetrel Bonding Interactions: Spectroscopic Study Of Halide-Carbonyl Sulfide Complexes, Christian T. Haakansson, Peter D. Watson, Timothy R. Corkish, Hayden T. Robinson, Allan J. Mckinley, Duncan A. Wild

Research outputs 2022 to 2026

Chalcogen and tetrel intermolecular bonding interactions formed between carbonyl sulfide and halide anions have been studied utilizing a combined experimental and theoretical approach. In particular, high-level CCSD(T) energetics and experimental anion photoelectron spectroscopy have been used in order to assign the dominant binding motif exhibited in these complexes. Halide anions solvated by multiple carbonyl sulfide molecules have also been investigated in order to ascertain the effect that additional binding partners has on the strength of the noncovalent interactions. The experimental and computational results support the main binding motif of carbonyl sulfide molecules with halide anions being chalcogen bonding, both in …

Development And Praxis Of Ph Drug Delivery System Contra Zika, Julissa Rodriguez

College of Graduate Studies: Theses & Dissertations

As the effects of global warming continue to spread throughout the world, another critical issue is slowly gaining attention in many urban tropical countries. The Emerging Infectious Diseases/ Pathogens list from the National Institutes of Health (NIH) listed the Zika virus as a potential pandemic threat. In 2015, an outbreak of Zika was noted in several South American countries until the spread reached an all-time high of 87 countries in 2017. During the outbreaks, adults affected were noted to have joint and muscle pains, fevers, and rashes. The worst cases reported would ultimately lead to Guillain-Barre symptoms. Still, pregnant women …

A Comparison Of Tung Oil Resin Reinforcements Using Fibrous Proteins And Peptides For Biological And Materials Applications, Parker L. Williams

College of Graduate Studies: Theses & Dissertations

In this study a tung oil based thermoset was reinforced with collagen and fibroin, and the resulting composites were analyzed for their physical properties. Tung tree seed oil is a great candidate for biobased polymer production because its triglycerides are primarily made of alpha eleostearic acid, a fatty acid with three conjugated carbon-carbon double bonds. These double bonds allow for mechanically strong crosslinking in the polymer. It has been observed that polymerized tung oil forms a gel. This issue has been addressed using divinylbenzene (DVB) and n-butyl methacrylate (BMA) as co-monomers. Similar bio-based polymers have been studied and tend to …

Deposited Cigarette Smoke As A Driver Of Oxidation And Partitioning Processes On Indoor Surfaces, April Hurlock

Honors Theses

Despite the large amount of time that individuals spend indoors during their lives, very little attention was paid to the chemistry that occurs on indoor surfaces until recently. Although not visible to the naked eye, physical and chemical processes, such as partitioning and oxidation, are occurring on virtually every indoor surface in a typical household. Indoor pollutants, ranging from skin oils to environmental cigarette smoke, drive a lot of these processes. The transformation of indoor surfaces by indoor pollutants can increase chemical exposure risks as new irritants or carcinogens can be introduced to the surfaces. In this thesis, I describe …

Polymeric Nanoparticle-Based Electrochemical Sensor For The Detection Of Ca 125, Ceren Türkcan, Si̇nan Akgöl

Turkish Journal of Chemistry

In this paper, Cys-graft-p(HEMA) nanomaterials and a new electrochemical method were developed for determination of CA 125. Cys-graft-p(HEMA) nanomaterials were synthesized with emulsion polymerization method and modified with grafting procedure. It was determined that Cys-graft-p(HEMA) nanomaterials had 50 nm dimension and spherical morphology, and per gram polymeric material contained 0.011 mmol L-cysteine. Electrode surface was prepared step by step for electrochemical analysis with optimization process. Linear determination range was determined as 5-400 U/mL (R= 0.9935). Detection limit (LOD) was calculated as 1.87 U/mL, and quantification limit (LOQ) was determined as 5.62 U/mL. The fabricated sensor system showed good repeatability, accuracy, …

Carbon Quantum Dots And Chitosan-Based Heterogeneous Silver Catalyst For Reduction Of Nitroaromatic Compounds, Farah Sami̇r Sali̇m, İdri̇s Sargin, Gülşi̇n Arslan

Turkish Journal of Chemistry

Chitosan plays a crucial role in catalysis, environmental remediation, and sustainable chemistry as a renewable and cationic polysaccharide. Chitosan-based metal catalysts are used in a broad range of chemical transformations. In the study, carbon quantum dots (CQDs) were derived from Momordica charantia fruits by microwave irradiation following a green chemistry approach. Three catalysts were designed: Ag(0)-chitosan, Ag(0)-chitosan-M. charantia fruit powder, and Ag(0)-chitosan-CQDs. The catalyst supports were prepared by stabilizing CQDs or M. charantia powder within the polymeric matrix of chitosan beads. Metallic silver particles were anchored onto glutaraldehyde cross-linked chitosan beads from the aqueous solution of silver nitrate. The …

Synthesis Optimization Of Zro2 Nanostructures For Photocatalytic Applications, Fi̇li̇z Boran, Merve Okutan

Turkish Journal of Chemistry

This study aims to optimize the synthesis of semiconductor zirconia (ZrO2) nanoparticles for future photocatalytic applications in degradation of pollutants in wastewater under ultraviolet (UV) light. The synthesis procedure of ZrO2 nanoparticles was optimized by examining the effects of synthesis methods (ultrasound-assisted, hydrothermal method in an autoclave and conventional precipitation), reaction time (2, 6, 10, and 18 h), ambient pH (3, 7, 10, 13), and surfactant type (anionic, cationic, and non-ionic), on the particle size and crystal phase of the nanomaterial. The characterization of the synthesized samples was performed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray …

In Vitro Tyrosinase Inhibitory, Dna Interaction Studies, And Lc?Hrms Analysis Of Ficus Carica Leaves, Güli̇n Renda, Burak Barut, Rümeysa Ceren, Enes Aydin

Turkish Journal of Chemistry

Turkey is the world?s leading producer of figs, a typical Mediterranean fruit. The fig, Ficus carica L. (Moraceae), has been widely cultivated since ancient times due to the nutritional value of its fruits. It was aimed to investigate the phytochemical characterization and biological properties of F. carica leaf extracts in order to determine their potential for use in the treatment of various diseases. F. carica leaves were extracted in 70% methanol at 40 °C under reflux. To obtain extracts of different polarities, the crude extract was fractionated with n-hexane, dichloromethane, and n-butanol. Phenolic content was determined using liquid chromatography?high resolution …

New Pyrimidine-N-Ss-D-Glucosides: Synthesis, Biological Evaluation, And Molecular Docking Investigations, Nuran Kahri̇man, Kivanç Peker, Vi̇ldan Serdaroğlu, Ali̇ Aydin, Burçi̇n Türkmenoğlu, Asu Usta, Nuretti̇n Yayli

Turkish Journal of Chemistry

In this study, syntheses of new pyrimidine-coupled N-ß-glucosides and tetra-O-acetyl derivatives were carried out. All glycoconjugates were investigated in comparison with known chemotherapeutic agents in terms of their antimicrobial and anticancer functions and DNA/protein binding affinities. Spectral data showed that all glycoside derivatives were obtained by diastereoselectivity as ß-anomers. Both tested groups exhibited strong antiproliferative activity (2.29?66.84 ?g/mL), but some of them had sufficiently ideal % cytotoxicity values (10.01%?16.78%). And also all synthetic compounds exhibited remarkable antibacterial activity against human pathogenic bacteria. Binding of these compounds to CT-DNA resulted in significant changes in spectral properties, consistent with groove binding. Molecular …

Theoretical Investigation Of Steric Effects On The S1 Potential Energy Surface Of O-Carborane-Anthracene Derivatives, Fahri̇ Alkan

Turkish Journal of Chemistry

TDDFT scan calculations were performed for s-carborane-anthracene derivatives (o-CB-X-Ant where X=-H, -CH3, -C2H5 and tert-butyl or -tBu) in order to understand the interplay between the steric effects, S1 potential energy surface (PES) and photophysical properties. The results show that all systems exhibit three local minima on the S1 PES, which correspond to the emissive LE and TICT state, along with the nonemissive CT state respectively. In the case of the unsubstituted system (o-CB-H-Ant), and -CH3 and -C2H5 substituted cases, S1 PES is predicted to be quite flat for certain conformations indicating that it is possible for these systems to reach …