Chemistry Commons^™

Synthesis Of Cerium Oxide Nanorods, Chin Li Cheung, Zane Charles Gernhart

Department of Chemistry: Faculty Publications

Cerium oxide nanorods having a variety of aspect ratios can be produced by providing a first mixture that includes a cerium precursor material, and using microwave to heat the first mixture to a first temperature for a period of time to produce first plurality of cerium oxide nanorods having a first range of aspect ratios. A second mixture that includes a cerium precursor material heated using microwave to a second temperature for a period of time to produce second plurality of cerium oxide nanorods having a second range of aspect ratios. The first plurality of cerium oxide nanorods and the …

Human Serine Racemase Structure/Activity Relationship Studies Provide Mechanistic Insight And Point To Position 84 As A Hot Spot For Β-Elimination Function, David L. Nelson, Greg A. Applegate, Matthew L. Beio, Danielle L. Graham, David B. Berkowitz

Department of Chemistry: Faculty Publications

There is currently great interest in human serine racemase, the enzyme responsible for producing the NMDA co-agonist D-serine. Reported correlation of D-serine levels with disorders including Alzheimer’s disease, ALS, and ischemic brain damage (elevated D-serine) and schizophrenia (reduced D-serine) has further piqued this interest. Reported here is a structure/activity relationship study of position Ser⁸⁴, the putative re-face base. In the most extreme case of functional reprogramming, the S84D mutant displays a dramatic reversal of β-elimination substrate specificity in favor of L-serine over the normally preferred L-serine-O-sulfate (~1200-fold change in k_cat/K_{m …}

Assessment Of Metabolic Changes In Mycobacterium Smegmatis Wild Type And Alr Mutant Strains: Evidence For A New Pathway Of D-Alanine Biosynthesis., Darrell D. Marshall, Steven Halouska, Denise K. Zinniel, Robert J. Fenton, Katie Kenealy, Harpreet K. Chahal, Govardhan Rathnaiah, Raul G. Barletta, Robert Powers

Department of Chemistry: Faculty Publications

In mycobacteria, D-alanine is an essential precursor for peptidoglycan biosynthesis. The only confirmed enzymatic pathway to form D-alanine is through the racemization of L-alanine by alanine racemase (Alr, EC 5.1.1.1). Nevertheless, the essentiality of Alr in Mycobacterium tuberculosis and Mycobacterium smegmatis for cell survivability in the absence of D-alanine has been a point of controversy with contradictory results reported in the literature. To address this issue, we examined the effects of alr inactivation on the cellular metabolism of M. smegmatis. The M. smegmatis alr insertion mutant TAM23 exhibited essentially identical growth to wild type mc²155 in the …

Transcriptional And Antagonistic Responses Of Biocontrol Strain Lysobacter Enzymogenes Oh11 To The Plant Pathogenic Oomycete Pythium Aphanidermatum, Yangyang Zhao, Guoliang Qian, Yuan Chen, Liangcheng Du, Fengquan Liu

Department of Chemistry: Faculty Publications

Lysobacter enzymogenes is a ubiquitous, beneficial, plant-associated bacterium emerging as a novel biological control agent. It has the potential to become a new source of antimicrobial secondary metabolites such as the Heat-Stable Antifungal Factor (HSAF), which is a broad-spectrum antimycotic with a novel mode of action. However, very little information about how L. enzymogenes detects and responds to fungi or oomycetes has been reported. An in vitro confrontation bioassay between the pathogenic oomycete Pythium aphanidermatum and the biocontrol bacterial strain L. enzymogenes OH11 was used to analyze the transcriptional changes in the bacteria that were induced by the oomycetes. Analysis …

Ion Mobility-Resolved Collision-Induced Dissociation And Electron Transfer Dissociation Of N-Glycopeptides: Gathering Orthogonal Connectivity Information From A Single Mass- Selected Precursor Ion Population, Venkata Kolli, Katherine N. Schumacher, Eric Dodds

Department of Chemistry: Faculty Publications

Glycopeptide-level mass spectrometry (MS) and tandem mass spectrometry (MS/MS) analyses are commonly performed to establish site-specific protein glycosylation profiles that are of central importance to gaining structure-function insights on glycoproteins. Confoundingly, the complete characterization of glycopeptide connectivity usually requires the acquisition of multiple MS/MS fragmentation spectra. Complementary ion fragmentation techniques such as collision-induced dissociation (CID) and electron transfer dissociation (ETD) are often applied in concert to address this need. While structurally informative, the requirement for acquisition of two MS/MS spectra per analyte places considerable limitations upon the breadth and depth of large-scale glycoproteomic inquiry. Here, a previously developed method of …

Identification Of “Kratom” (Mitragyna Speciosa) Alkaloids In Commercially Available Products, Julia Grzymkowski, Michelle R. Peace, Justin Poklis

Undergraduate Research Posters

“Kratom” is the common name for the botanical mitragyna speciosa. It is a tree native to Southeast Asia in which leaves contain the psychoactive alkaloids mitragynine and 7-hydroxymitragynine. Kratom is often ingested as teas, chewed, or smoked. It acts as a stimulant in small doses and as an opioid in large doses. Overdoses can result in vomiting, seizures, and death. Recently the Drug Enforcement Agency (DEA) placed Kratom on Schedule 1, but, due to public outcry, it was almost immediately removed.

Eleven kratom based products were obtained from various tobacco shops, “headshops” and via the internet including: Choice brand …

Measuring And Modeling Nmr And Emission Spectra To Gain New Insight Into Challenging Organic Compounds, Jacob Powell

Electronic Theses and Dissertations

The advancement of theoretical methods in recent years has allowed the calculation of highly accurate spectroscopic parameters. Comparing these values to the corresponding experimental data can allow molecular structures to be elucidated. This dissertation details the use of experimental and theoretical data from nuclear magnetic resonance (NMR) and fluorescence spectroscopy to determine structure. Herein the NMR focus is on measuring & modeling chemical shift anisotropy and one-bond carbon-carbon J-coupling constants (1JCC). The fluorescence analysis models vibrationally resolved fluorescence spectra. Chemical shift anisotropy techniques were used to study two conflicting crystal structures of the n-alkyl fatty acid, lauric acid. These two …

การขจัดสีย้อมในน้ำเสียจากอุตสาหกรรมกระดาษไหว้เจ้าโดยการดูดซับบนคอมพอสิตแร่ดิน-ไคโตซาน, วิศรุต ม่วงรักษ์

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้มีจุดประสงค์เพื่อศึกษาการขจัดสีย้อมรีแอคทีฟเรด 120 ในน้ำ โดยการดูดซับบนตัวดูดซับคอมพอสิตแร่ดิน-ไคโตซาน และเปรียบเทียบกับตัวดูดซับไคโตซาน ซึ่งการทดลองนี้จะศึกษาการดูดซับแบบกะ โดยตัวแปร ที่ศึกษาในการทดลอง คือ ปริมาณตัวดูดซับ ความเข้มข้นเริ่มต้นของสารละลายสีย้อม ค่าความเป็นกรดด่าง โดยเวลาที่ใช้ในการดูดซับ ตั้งแต่ 15 นาทีถึง 420 นาที จากการวิเคราะห์คุณลักษณะของตัวดูดซับโดยใช้ใช้เทคนิคฟูเรียร์ทรานส์ฟอร์มอินฟราเรดสเปกโทรสโกปี (FTIR) พบว่าตัวดูดซับคอมพอสิตแร่ดิน-ไคโตซานจะมีลักษณะสเปกตรัมเฉพาะที่สะท้อนถึงตัวดูดซับไคโตซานและตัวดูดซับแร่ดินอย่างชัดเจน เมื่อพิจารณาพื้นที่ผิวการดูดซับโดยใช้เทคนิคการดูดซับ/การคายซับไนโตรเจน พบว่าแนวโนมของการเพิ่มสัดส่วนของแร่ดินจะช่วยเพิ่มพื้นที่ผิวให้กับตัวดูดซับคอมพอสิตแร่ดิน-ไคโตซาน ส่งผลให้ตัวดูดซับคอมพอสิตแร่ดิน-ไคโตซาน มีพื้นที่ผิวที่สูงกว่าตัวดูดซับไคโตซาน เนื่องจากไคโตซานเข้าไปแทรกในโครงสร้างของแร่ดิน สามารถอธิบายด้วยเทคนิคเอกซเรย์ฟลูออเรสเซนต์ (XRF) ทำให้โครงสร้างของแร่ดินเกิดการขยายขนาดขึ้น สำหรับผลจากการศึกษาตัวแปรต่างๆ พบว่า ตัวดูดซับคอมพอสิตแร่ดิน-ไคโตซาน มีประสิทธิภาพในการกำจัดสีย้อมได้ดีกว่าตัวดูดซับไคโตซานและตัวดูดซับแร่ดิน ถึง 1.17 เท่า และ 1.88 เท่า ตามลำดับ การเพิ่มปริมาณตัวดูดซับจะช่วยลดระยะเวลาในการดูดซับให้เร็วยิ่งขึ้น สำหรับตัวดูดซับคอมพอสิตแร่ดิน-ไคโตซาน พบว่าสามารถกำจัดสีย้อมได้หมดสมบูรณ์ทุกความเข้มข้น และสามารถกำจัดสีย้อมได้ดีสำหรับทุกช่วงของค่าความเป็นกรดด่างที่ได้ศึกษาในงานวิจัย แบบจำลองสมดุลการดูดซับของตัวดูดซับคอมพอสิตแร่ดิน-ไคโตซาน สอดคล้องกับแบบจำลองการดูดซับของโกเบิลคอร์ริแกน จลนพลศาสตร์การดูดซับของตัวดูดซับคอมพอสิตแร่ดิน-ไคโตซาน มีอัตราเร็วของปฏิกิริยาการดูดซับสารละลายสีย้อมเป็นปฏิกิริยาอันดับสองเทียม นอกจากนี้ยังพบว่ากลไกในการควบคุมขั้นตอนการดูดซับคือ ขั้นตอนการของการแพร่ผ่านชั้นฟิล์ม และขั้นตอนของการแพร่ภายในรูพรุน สำหรับการศึกษาอุณหพลศาสตร์ของการดูดซับพบว่าตัวดูดซับคอมพอสิตแร่ดิน-ไคโตซาน สามารถเกิดขึ้นได้เองและเกิดขึ้นได้ดีที่อุณหภูมิสูง

การใช้สารดูดซับรังสียูวีและสารต้านอนุมูลอิสระสำหรับการปรับปรุงความคงทนต่อแสงของสีธรรมชาติบนเส้นด้ายฝ้ายและไหม, สุรพันธ์ เปล่งเจริญศิริชัย

Chulalongkorn University Theses and Dissertations (Chula ETD)

ปัจจุบันผลิตภัณฑ์สิ่งทอที่ย้อมด้วยสีย้อมธรรมชาติเป็นที่นิยมมากทั้งในและต่างประเทศ อย่างไรก็ตาม ผลิตภัณฑ์ที่ใช้สีจากธรรมชาติยังคงมีปัญหาด้านความคนทนของสีต่อแสงซึ่งเป็นปัจจัยอย่างหนึ่งที่สำคัญในการใช้งานในชีวิตประจำวัน งานวิจัยนี้แสดงการศึกษาสมบัติด้านความคงทนต่อแสงของสีย้อมธรรมชาติบนเส้นด้ายฝ้ายและไหมจากแหล่งให้สี 4 ชนิด ได้แก่ ครั่ง (สีแดงอมม่วง) เปลือกของต้นมะพูด (สีเหลือง) ดอกดาวเรือง (สีเหลือง) และเมล็ดคำแสด (สีส้ม) โดยศึกษาตั้งแต่การสกัดสีย้อมธรรมชาติ กระบวนการย้อมสีบนเส้นด้ายฝ้ายและไหม การมอร์แดนต์ วิธีการมอร์แดนต์ (พร้อม/หลังการย้อม) และทดสอบความคงทนของสีต่อแสงเพื่อคัดเลือกสีบนเส้นด้ายที่มีความคงทนต่อแสงน้อยที่สุดมาปรับปรุงให้เส้นด้ายย้อมสีมีความคงทนต่อแสงมากขึ้นหรือเกิดการเปลี่ยนแปลงของสีน้อยลง จากผลการวิจัยพบว่าการย้อมสีธรรมชาติจำเป็นต้องมีการมอร์แดนต์ โดยที่การย้อมสีจากครั่งและเปลือกของต้นมะพูดใช้การมอร์แดนต์พร้อมการย้อม การย้อมสีจากดอกดาวเรืองและเมล็ดคำแสดใช้การมอร์แดนต์หลังการย้อม จากการศึกษาความคงทนของสีต่อแสงของเส้นด้ายฝ้ายและไหมย้อมสีธรรมชาติทั้ง 4 ชนิด พบว่าสีย้อมจากเมล็ดคำแสดมีความคงทนของสีต่อแสงน้อยที่สุด ดังนั้นงานวิจัยนี้จึงทำการปรับปรุงความคงทนของสีย้อมจากเมล็ดคำแสดต่อแสงบนเส้นด้ายฝ้ายและไหมโดยวิธีการตกแต่งสำเร็จต่างๆ (ตกแต่งสำเร็จก่อน/พร้อม/หลังการย้อม) ด้วยสารดูดซับรังสียูวีทางการค้า Rayosan®C Paste และสารต้านอนุมูลอิสระชนิดไวตามินซี (กรดแอสคอร์บิก) ผลการวิจัยชี้ให้เห็นว่า การตกแต่งสำเร็จหลังการย้อมบนเส้นด้ายฝ้ายและไหมด้วยสารต้านอนุมูลอิสระความเข้มข้น 20 กรัมต่อลิตร และ 10 กรัมต่อลิตร ตามลำดับ ทำให้สีบนเส้นด้ายมีการเปลี่ยนแปลงหลังการตกแต่งสำเร็จน้อยที่สุดและช่วยทำให้ความคงทนของสีต่อแสงเพิ่มขึ้นมากที่สุด การทดสอบสมบัติด้านอื่นๆ ของเส้นด้าย พบว่าการตกแต่งสำเร็จทำให้สมบัติด้านความคงทนต่อการซักของสีบนเส้นด้ายดีมากขึ้น แต่ไม่ส่งผลกระทบต่อความแข็งแรงและร้อยละการยืดตัวของเส้นด้าย

Development Of Poly(Aryleneethynylene)S Synthesis And Application As Fluorescent Sensor, Nopparat Thavornsin

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this research, we focus on preparation and sensor application of poly(aryleneethynylene)s. Our work is divided into two parts. The first study relates to the utilization of salicylaldimine-functionalized poly(m-phenyleneethynylene) as a turn-on chemosensor for ferric ion (Fe3+). The second part is the preparation of highly pure poly(aryleneethtnylene)s using Pd/CaCO3 as a heterogeneous catalyst. In the first part, a new turn-on fluorescent probe for ferric ion based on poly(m-phenyleneethynylene salicylaldimine) (PPE-IM) is developed. The preparation of PPE-IM involves post-polymerization functionalization of corresponding polymeric amine, PPE-AM, via condensation with salicylaldehyde. Degree of polymerization of both PPE-AM and PPE-IM are 17 with polydispersity …

Chemical Constituents From The Roots Of Calophyllum Calaba L., Fuengfa Laopian

Chulalongkorn University Theses and Dissertations (Chula ETD)

Phytochemical investigation of the CH2Cl2 extract from the roots of C. calaba let to the isolation of three new xanthone derivatives, namely calaxanthones A-C (1-3), along with twenty nine known xanthones (4-32). The structures of all isolated compounds were fully characterized using spectroscopic data (1D and 2D NMR) as well as comparison with the previous literature data. Moreover, all isolated compounds were assessed for their in vitro cytotoxicity against the KB, HeLa S-3, HT29, MCF-7 and HepG2 human cancer cell lines. The tested compounds mostly showed moderate to inactive against these five cell lines, except compounds 3 showed potent cytotoxicity …

Formation Of Titan Aerosol From Co And Ch4, Tate Christensen

Honors Program Theses

In 1952 Stanley Miller and Harold Urey conducted an experiment that would simulate the conditions of early earth (Miller, 1953). The purpose was to observe the chemical origins of life, and the conclusion supported an earlier theory that such conditions favor the synthesis of more complex organic compounds from simpler inorganic molecules. The research conducted in Dr. Sebree’s lab is an extension of these early findings. It is believed that early Earth was composed mostly of nitrogen, carbon monoxide, carbon dioxide and methane as opposed to our atmosphere of nitrogen and oxygen today.

Saturn’s largest moon, Titan, has qualities relatively …

Phage Display To Identify Functional Resistance Mutations To Rigosertib, Nedim Filipovic

CMC Senior Theses

In vitro protein selection has had major impacts in the field of protein engineering. Traditional screens assay individual proteins for specific function. Selection, however, analyzes a pool of mutants and yields the best variants. Phage display, a successful selection technique, also provides a reliable link between variant phenotype and genotype. It can also be coupled with high throughput sequencing to map protein mutations; potentially highlighting vital mutations in variants. We propose to apply this technique to cancer therapy. RAF, a serine/threonine kinase, is critical for cell regulation in mammals. RAF can be activated by oncogenic RAS, found in over 30% …

Detection Of Inorganic Phosphate In Environmental Water Samples Using A Terbium And Gold Nanoparticle-Based Fret Chemosensor, Madeleine Johnson

Electronic Theses and Dissertations

A novel chemosensor for the detection of inorganic phosphate (Pi) in environmental water samples is outlined. The sensing solution is comprised of a luminescent lanthanide, terbium (Tb3+), chelated to ethylenediaminetetraacetic acid (EDTA) acid in solution with cetyltrimethylammonium bromide (CTAB)- capped gold nanoparticles (AuNPs). The Tb-EDTA and AuNPs undergo a Fluorescence resonance energy transfer (FRET) mechanism in which the Tb3+ luminescence is quenched. Upon the addition of inorganic phosphate (Pi), the AuNPs begin to aggregate and precipitate out of solution. The aggregation of AuNPs results in the restoration of the Tb-EDTA signal which can then be correlated to Pi concentration in …

Assessment Of Short-Term Toxicity Of Titanium Dioxide Nano Fiber (Tdnf) In Sprague Dawley Rats, Daniel A. Hunter

College of Graduate Studies: Theses & Dissertations

Nanotechnology is easily becoming one of the fastest growing markets around the globe. Synthetic nanomaterials have many unique chemical and physical properties, mainly due to their huge specific surface area and chemical makeup. Specifically, titanium dioxide (TiO₂) nanomaterials have high stability, anticorrosive and photocatalytic properties. These nanomaterials have applications for semiconductor photocatalysis, treatment of water, as a photoactive material in nanocrystalline solar cells, and medicine. However, not much is known about the toxicity of TiO₂ in the nanofiber form. The objective of the present study is to investigate the adverse effects associated with acute ingestion of TiO …

Α-Eleostearic Acid Extraction By Saponification Of Tung Oil And Its Subsequent Polymerization, Amanda Murawski

College of Graduate Studies: Theses & Dissertations

The goal of environmentally sound research is to provide alternatives that are more sustainable and renewable, such as vegetable oil-based polymers, than the current petroleum-based products. Vegetable oil-based polymers have received a lot of attention recently due their multifaceted properties, which are simply achieved by adjusting the monomer or resin composition. The carbon-carbon double bonds in unsaturated oils are ideal reactive sites for the free radical or cationic polymerizations. Most vegetable oils must be modified before polymerization due to the low reactivity of their non-conjugated fatty acid chains. Tung oil (TO) contains ~83% of a triply conjugated fatty acid ( …

Manifestations Of Classical Physics In The Quantum Evolution Of Correlated Spin States In Pulsed Nmr Experiments, Martin K. Ligare

Faculty Journal Articles

Multiple-pulse NMR experiments are a powerful tool for the investigation of mole- cules with coupled nuclear spins. The product operator formalism provides a way to understand the quantum evolution of an ensemble of weakly coupled spins in such experiments using some of the more intuitive concepts of classical physics and semi- classical vector representations. In this paper I present a new way in which to inter- pret the quantum evolution of an ensemble of spins. I recast the quantum problem in terms of mixtures of pure states of two spins whose expectation values evolve identi- cally to those of classical …

Relationship Of The Fractal And Chemical Characteristics Of Self-Assembled Natural Organic Matter, Dennis K. Gibson

Electronic Theses and Dissertations

Natural Organic Matter (NOM) is a heterogeneous mixture formed by the degradation of organic substances during early diagenesis in surficial environments. It has been shown that the interaction of the components that comprise this mixture has a significant impact on its microbial mineralization to CO₂. The extent of NOM selfassembly is emerging as an important factor in understanding its role in the global geochemical carbon cycle, and it is beginning to appear that it may be more important than the chemical composition of a sample. The overall goal of this research is to establish NOM’s self-assembled “architecture” and …

Cadmium Disruption Of Calcium-Dependent Dimerization Of Neural Cadherin, Dylan Ritter

Honors Theses

Cadherins are a family of transmembrane proteins that dimerize to form junctions between cells in the presence of calcium. Due to the necessity for proper cell adhesion during cell differentiation in development, we are examining whether binding of other metallic divalent cations would disrupt calcium-sensitive dimerization of neural cadherin in vitro. Specifically, we are studying the effect of cadmium(II) on the linkage between calcium binding, dimerization, and dimer disassembly. Cadmium toxicity became recognized during the Industrial Revolution, with particular attention gained during the Itai-Itai disease outbreak in China during the 1910s. This toxicity, partnered with the role of cadherin in …

Infusion Of Essentail Oils In Agarose Gels To Create Antimicrobial Surfaces, Simran Guron

Honors College Theses

The current use of antibiotics is very excessive in multiple settings, from treating patients to being present in cleaning products. This overuse of antibiotics is resulting in multiple consequences, ranging from having a negative impact on human health to breeding antibiotic-resistant strains of microorganisms. Antimicrobial surfaces are useful today to aid in sterilization, especially in the medical setting. This would help prevent the spread of infection of microorganisms in these settings. In our research, agarose acts as the antimicrobial surface and essential oils would act as the solution incorporated into the surface that has the antimicrobial properties. Agarose is a …

Comparative Proteomic Analyses Of The Parietal Lobe From Rhesus Monkeys Fed A High-Fat/Sugar Diet With And Without Resveratrol Supplementation, Relative To A Healthy Diet: Insights Into The Roles Of Unhealthy Diets And Resveratrol On Function, Aaron M. Swomley, Judy C. Triplett, Jeriel T. Keeney, Govind Warrier, Kevin J. Pearson, Julie A. Mattison, Rafael De Cabo, Jian Cai, Jon B. Klein, D. Allan Butterfield

Chemistry Faculty Publications

A diet consisting of a high intake of saturated fat and refined sugars is characteristic of a Western-diet and has been shown to have a substantial negative effect on human health. Expression proteomics were used to investigate changes to the parietal lobe proteome of rhesus monkeys consuming either a high fat and sugar (HFS) diet, a HFS diet supplemented with resveratrol (HFS+RSV), or a healthy control diet for 2 years. Here we discuss the modifications in the levels of 12 specific proteins involved in various cellular systems including metabolism, neurotransmission, structural integrity, and general cellular signaling following a nutritional intervention. …

Correlation Between The Structure And The Anticorrosion Barrier Properties Of Hybrid Sol–Gel Coatings: Application To The Protection Of Aa2024-T3 Alloys, Maikki Cullen, Muhammad Morshed, Mary O'Sullivan, Emma Mchugh, Brendan Duffy, Mohamed Oubaha

Articles

Hybrid sol–gel materials have been extensively studied as viable alternatives to toxic chromate (VI)-based coatings for the corrosion protection of AA2024-T3 in the aerospace industry, due to the wide range of available chemistries they offer and the tremendous development potential of innovative functional coatings. However, so far, little work has been performed in identifying the effect of the employed chemistries on the structure and anticorrosion properties of the coatings. This work proposes to contribute to a better understanding of the relationship existing between the structure, morphology and anticorrosion properties of hybrid sol–gel coatings deposited on AA2024- T3 aluminium surfaces, the …

Synthesis Of Ag10 Analogs And Optimization Of Ttr Ligands For Half-Life Enhancement (Tlhe) Of Peptides, Raghavendra Jampala

University of the Pacific Theses and Dissertations

The misassembly of soluble proteins into toxic aggregates, including amyloid fibrils, underlies a large number of human degenerative diseases. Cardiac amyloidosis, which is most commonly, caused by aggregation of Immunoglobulin (Ig) light chains or transthyretin (TTR) in the cardiac muscle, represent an important and often underdiagnosed cause of heart failure. TTR-mediated amyloid cardiomyopathies are chronic and progressive conditions that lead to arrhythmias, biventricular heart failure, and death. As no Food and Drug Administration-approved drugs are currently available for treatment of these diseases, the development of therapeutic agents that prevent TTR-mediated cardiotoxicity is desired. AG10 is a potent and selective kinetic …

Investigating Stress Response Across Integrated Biological Systems, Alice A. Han

Graduate Theses, Dissertations, and Problem Reports (ETD)

The impact that a stressor has on a living system, whether it is on a cellular, organ, or even a whole organism level, can affect the overall health of the system. Monitoring the biochemical response resulting from a stressful experience offers insight into the numerous potential outcomes ranging on the spectrum of survival and death. Accessing this information not only provides a heightened understanding of the biochemical adaptions that occur, but also allows for the development of prediction models (to assess prospective influences of the stressor) or potential therapeutic treatments (to alleviate adverse effects) using measurable, quantifiable, and comparable metrics. …

Cloud Point Extraction In Conjunction With Tangential Flow Filtration (Cpe-Tff) For The Enhanced Separation Of Silver Nanoparticles And Silver Ions From Aqueous Colloids And Biological Matrices, Md Ali Akbar

Browse all Theses and Dissertations

The extensive use of silver nanoparticles (AgNPs) in consumer products and research is accompanied by their inevitable release into the environment. While the environmental fate of AgNPs is still under investigation, most in vitro and in vivo studies agree that the main toxicity of AgNPs is directly related to the release of Ag+ ions from AgNPs. In this study, cloud point extraction (CPE) was combined with tangential flow filtration (TFF) for the enhanced separation of AgNPs and Ag+ from aqueous colloids and biological matrices. The feasibility of the CPE-TFF method was demonstrated on four colloidal (borohydride-, PVP-, citrate-capped and uncapped …

Behavior Of Different Sizes Of Strontium Titanate Substrates In Electrochemical Modifications, Shuxin Luo

Masters Theses

In our previous atomic force microscopy (AFM) studies of 5 mm x 5 mm single crystal SrTiO₃ (STO(100)) substrates, rutile TiO₂ crystals were found on the substrates surfaces after electrochemical modification. These crystals were found mainly in the area of contact between the substrate and the gold-coated alligator clip that was not supposed to be immersed into the electrolyte and that served as a connection between the STO working electrode and the potentiostat circuit. The size and density of the crystals were found to depend on electrochemical potential, its polarity, the length of modifying time, and the total …

Functionalized Bodipy Dyes For Near-Infrared Emission Of Lanthanide Complexes, Rukshani Wickrama Arachchi

Masters Theses

For many decades, fluorophores have been used to investigate natural systems, but autofluorescence and photobleaching diminish the detection capacity. Recently, BODIPY based lanthanide complexes have been synthesized and their photophysical properties have been investigated. These complexes exhibit higher emission efficiencies at NIR region with longer NIR lifetimes upon exciting at longer wavelength.

In this study, two BODIPY based lanthanide complexes were synthesized and their photophysical properties were evaluated. BODIPY based ligands were synthesized with phenanthroline as the ligand binding group. These ligands exhibit strong absorption at 527 nm and 532 nm, fluorescence at 540 nm and 548 nm with 0.55 …

Bodipy-Based Red Sensitizers For Near-Infrared Emission Of Lanthanide Complexes, Priyangika Prasadini Senevirathne

Masters Theses

During the past 20 years there has been a remarkable growth in the use of the fluorescence technique in biological studies. Fluorescence and time-resolved fluorescence spectroscopy are considered primary research tools in the field of biochemistry. Currently, fluorescence spectroscopy is a dominant methodology and used widely in biotechnology and medical diagnosis process. One impediment in using fluorescent probes is the fluorescence of biological substrates and fluorescence of diagnostic probes are significantly overlapped, and it decreases the detection sensitivity. Also, commercially available probes require UV or near-UV light excitation, causing severe degradation of biological substrates. Near-infrared emitting lanthanide complexes can overcome …

Molecular Recognition Profiles Of Molecular Cocrystals, Ian C. Tinsley

Masters Theses

The manner in which molecules recognize each other holds critical importance to nearly every area of science. This significance stems from the key underpinning of molecular assembly to our most basic understanding of chemical processes. Whether these interactions relate to small-molecule catalytic transformations or complex physiological processes, the structural features responsible for molecular association play into the well-known adage that form follows function where material property arises from the collective structural features of the molecular components. Because the form of chemical systems is derived from a complex blend of covalent and non-bonded contacts, codifying each contributor has become essential for …

Time-Resolved Phosphorescence Spectroscopy At Cryogenic Temperatures For The Environmental Analysis Of Polycyclic Aromatic Sulfur Heterocycles In Oil Contaminated Sites., Maha Al-Tameemi

Electronic Theses and Dissertations

The large volume of crude oil released into the Gulf of Mexico by the Deepwater Horizon (DWH) accident has raised considerable concerns over potential ecosystem impacts. The dispersion of harmful oil components into the ocean waters could pose long term risks to flora and fauna. Due to the complexity of oil contaminated sites, the unambiguous identification and quantitation of environmental pollutants often requires the sequence of high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS). A classic example is the analysis of the sixteen polycyclic aromatic hydrocarbons included in the priority pollutants list of the U.S. Environmental Protection Agency (EPA-PAHs). …