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(1 - 11 of 11)
- Title
- Functionalized Polyoxovanadates: Synthesis, Characterization and Properties
- Creator
- Zheng, Yujuan
- Date
- 2012-04-30, 2011-12
- Description
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The compound [NaVIV6O6{(OCH2CH2)2NCH2CH2OH}6]Cl.H20, designated C0 in this report, an Anderson type structure, contains a single nitrogen atom...
Show moreThe compound [NaVIV6O6{(OCH2CH2)2NCH2CH2OH}6]Cl.H20, designated C0 in this report, an Anderson type structure, contains a single nitrogen atom in place of a single oxygen atom in each of the six vanadium-oxygen octahedra. Attached to each nitrogen are two alkoxide arms (-O-C-C-) which terminate on separate oxygen atoms of the octahedra. A third ethoxy group (-CH2-CH2-OH) dangles freely from each nitrogen atom. The functionalized cationic core [NaVIV6O6{(OCH2CH2)2NCH2CH2OH}6]+ is generated in situ and is cationic with a charge of +1. Chloride is the counteranion. Each vanadium addenda atom is the +4 oxidation state, and the six unpaired electrons result in interesting magnetic properties. C0 is obtained by reaction of a vanadium oxide source triethanolamine. The purpose of the research described here was to adapt the synthetic protocol associated with triethanolamine to other similar ligands. Ligand choice was motivated by the broader goal of this research group to form (extended) hybrid electronic and magnetic materials by chemically bonding POM cores to chemically interesting ligands, such as dyes or other POM cores. In this regard, the original triethanolamine derivative has a number of shortcomings; chief among them is the inaccessibility of the alcoholic functional group chemistry---due to its low pH---that otherwise might have been used to form linkages through the dangling alkoxy arms. Additionally, linkages containing paraffinic carbon (-C-C-), which is not a good conduit of electronic interaction, are chemically undesirable where the synthetic goal is hybrid structures with interesting electronic and magnetic properties. The results associated with the three ligands, diethanolamine, N,N'-Bis(2-hydroxyethyl)ethylenediamine, and N,N-Bis(2-hydroxyethy) ethylenediamine, are described herein. Diethanolamine was chosen because---based on a structural comparison to triethanolamine---it was expected to produce a structure having a hydrogen atom in place of the dangling ethoxy arms, which was indeed the result. We considered this structure highly desirable becasue of the potential lability of the hydrogen atom (-N-H), which would allow us to functionalist the core directly. The resulting compounds are characterized by single-crystal X-ray diffraction, elemental analysis, mass spectroscopy, thermogravimetric analysis, FT-IR and UV-Vis spectroscopy, maganometric titration, temperature-dependent magnetic susceptibility measurements, and cyclic voltammetry. The results of the cyclicvoltammetric investigation are consistent with the labile hydrogen atom (-N-H).
M.S. in Chemistry, December 2011
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- Title
- NANOPORE STOCHASTIC DETECTION OF ANTHRAX
- Creator
- Han, Yujing
- Date
- 2014, 2014-05
- Description
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Nanopore stochastic sensor using a biological protein ion channel has emerged as a powerful sensing technique due to its outstanding features...
Show moreNanopore stochastic sensor using a biological protein ion channel has emerged as a powerful sensing technique due to its outstanding features such as label- and amplification-free detection, rapidness, high sensivity and selectivity. Development of a nanopore stochastic sensor for the rapid detection of anthrax can effectively prevent and control the spread of disease infection, and become extremely useful in biodefense. Two sensor design strategies were studied: one is chemistry-based detection of dipicolinic acid; and the other is genetics-based detection of anthrax lethal factor. Both approaches used in this study should find useful application in the development of nanopore sensors for the detection of other biomolecules and pathogens.
M.S. in Chemistry, May 2014
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- Title
- STUDIES TOWARD TOTAL SYNTHESIS OF (-)-DEGUELIN
- Creator
- Li, Bao
- Date
- 2013-05-13, 2013-05
- Description
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Deguelin, as a rotenoid, has emerged as an attractive pharmacophore for chemprevention due to its effectiveness for both in vitro and in vivo...
Show moreDeguelin, as a rotenoid, has emerged as an attractive pharmacophore for chemprevention due to its effectiveness for both in vitro and in vivo models. The biological activity and its structural complexity instigated the development of new synthetic technologies which could satisfy the increasing demand of deguelin, as well as broaden the diversity of the rotenoids. Here, a strategy of asymmetric acid-catalyzed annulations toward the enantioselective total synthesis of (-)-deguelin will be discussed. Several approaches were investigated to connect the chromene and phenolic moieties to create the pentacyclic rotenoid skeleton. Meanwhile, by collaborating with Professor Rajendra Mehta, several derivatives of deguelin were also made to study its bioactivity and interaction modes with specific proteins.
M.S. in Chemistry, May 2013
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- Title
- BIFUNCTIONAL CHELATING AGENTS FOR POSITRON EMISSION TOMOGRAPHY AND RADIOIMMUNOTHERAPY
- Creator
- Sin, In Seok
- Date
- 2013, 2013-12
- Description
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Positron emission tomography (PET) is an important molecular imaging modality. To develop new bifunctional chelators for use in more sensitive...
Show morePositron emission tomography (PET) is an important molecular imaging modality. To develop new bifunctional chelators for use in more sensitive PET imaging, 64Cu-radiolabeled chelators have been investigated as promising PET agents. We synthesized and evaluated a macrocyclic chelator (NOTA)-based new bifunctional ligands with different coordination groups. New bifunctional chelators were evaluated for their radiolabeling efficiency with 64Cu, and in vitro complex stability of 64Cu-labeled chelators in human serum was also studied. 64Cu-labeled chelators was further evaluated for in vitro complex stability by EDTA challenge as a rigorous test of transchelation. As a result, chelator D, E, 3p-C-NE3TA, and 3p-C-NOTA were indicated as best chelators and have a promise for 64Cu-based PET imaging. Radioimmunotherapy (RIT) is a highly selective modality of cancer treatment and uses a radiolabeled chelator conjugated with monoclonal antibody. Our continued research of developing new RIT agents radiolabeled with 177Lu, different types of a macrocyclic based bifunctional chelators (DOTA, NOTA and NE3TA)- with variation of denticity, macrocyclic cavity, and bimodality were synthesized. Radiolabeling efficiency of chelators and in vitro complex stability of 177Lu-radiolabeled complex in human serum were evaluated. The effects of different pH and TLC solvents were investigated to confirm the best radiolabeling condition of new chelators with 177Lu. Furthermore, complex stability of 177Lu-radiolabeled chelators in a solution with excess EDTA and various metals was evaluated for transchelation. Therefore, the results of radiolabeling, serum stability and EDTA and metal challenge studies indicate that cavity size and ligand x denticity in chelators affected binding affinity to Lu(III) . 3p-C-DETA was identified as the best chelator for further research of RIT agent.
M.S. in Chemistry, December 2013
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- Title
- Amorphous Solid Polymer Electrolytes for Lithium-Ion Batteries
- Creator
- Lee, Sooyun
- Date
- 2012-07-05, 2012-07
- Description
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The rechargeable lithium-ion batteries that started in the early 1990’s, are extensively used in lots of electronic devices, including...
Show moreThe rechargeable lithium-ion batteries that started in the early 1990’s, are extensively used in lots of electronic devices, including cellular phones, laptop computers, camcorders, cameras and medical devices. Due to high energy and power density of lithium-ion batteries, they are one of the most useful batteries, and lots of researches and developments are still progressing, especially in electronic vehicle / hybrid electric vehicle (EV/HEV). However, current lithium-ion batteries have many problems, especially those related to its electrolyte system. Because this component contains flammable organic solvents, they have several disadvantages, such as leakage, instability, and difficulty in manufacture of large flat types of batteries. To eliminate these problems, the studies on Solid Polymer Electrolyte (SPE) system are now an active research area. In this thesis work, three different approaches have been executed to improve electrolyte properties of lithium-ion batteries. As a based material tosylate poly(ethylene glycol) was prepared, and a plasticizer was synthesized and incorporated into a conventional poly(ethylene oxide)-based Solid Polymer Electrolyte systems. First, to increase amorphousness in plasticizer, bisphenol-A was introduced, which has free rotating unit and only ionic conductivity was measured to verify. Secondly, hyperbranched poly(p-hydroxy styrene) derivatives were synthesized and used as the base matrix in SPEs. Polymers which have higher order of branching exhibited higher ionic conductivity, and it was assumed that branching structure lowered crystallinity. Finally, we synthesized 3-chloropropanesulfonyl-trifluoromethanesulfonylimide (LiCPSI) and attached to hyperbranched poly(p-hydroxy styrene) to verify that how hyperbranched structure would affect the ionic conductivity. Major characterization techniques include ionic conductivity, cyclic voltammetry (CV) and thermogravimetric analysis (TGA).
M.S. in Chemistry, July 2012
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- Title
- HYDROGEN BOND CATALYZED EPOXIDATION AND DIHYDROXYLATION OF UNACTIVATED ALKENES
- Creator
- Kang, Lili
- Date
- 2011-12, 2011-12
- Description
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Asymmetric epoxidation and dihydroxylation have been studied over decades using transition metals and chiral ligands. This research focused on...
Show moreAsymmetric epoxidation and dihydroxylation have been studied over decades using transition metals and chiral ligands. This research focused on metal free, hydrogen-bonding activation of the oxidant, such as hydrogen peroxide. In order to activate hydrogen peroxide, different types of catalysts, including BINOLs, calixarenes and carboxylic acids were synthesized, characterized and tested. The activity tests showed that carboxylic acids were able to activate hydrogen peroxide and alkyl hydroperoxides to give epoxides and diols as products. Various carboxylic acids, such as commercial available achiral and chiral carboxylic acids, dicarboxylic acids, as well as synthesized trans- and cis-dicarboxylic acid, were tested with different substrates to maximize the yield and enantioselectivity. A current reaction system uses 10 mol % catalyst, no solvent and provides the epoxide with 70% yield and 60% ee over 24 hours.
M.S. in Chemisty, December 2011
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- Title
- SYNTHESIS OF TETRAZINE-BASED COVALENT ORGANIC NETWORKS
- Creator
- Han, Songyang
- Date
- 2015, 2015-05
- Description
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After comparison of inorganic, hybrid and organic porous materials, tetrazine based organic porous material was chosen as a target material...
Show moreAfter comparison of inorganic, hybrid and organic porous materials, tetrazine based organic porous material was chosen as a target material since it was rigid material providing micro- to mesoscale pores and could do post-synthetic modifications through inverse electron demand Diels-Alder Reaction with different dienophiles. Such networks own the potential as catalysts after modifying with different metal chelation sites. Here, three strategies were provided to synthesize such materials. During of construction of building blocks through double Diels-Alder Reaction, reactivities of tetrazines and dienophiles were studied. The coupling study provided the information of which type of coupling reaction could be used as well as how it was proceeded. The Direct synthesis of tetrazine-based network through formation of tetrazines then broadened the variety materials that could be synthesized.
M.S. in Chemistry, May 2015
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- Title
- BLOCK COPOLYMER BASED MICELLE FOR EFFICIENT IMMUNOSENSING
- Creator
- Li, Ying
- Date
- 2012-11-26, 2012-12
- Description
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This thesis demonstrates the formation of micelles from a block copolymer and the application in establishing the micelle based immunosensing...
Show moreThis thesis demonstrates the formation of micelles from a block copolymer and the application in establishing the micelle based immunosensing system. The utilization of polymeric micelle as probe container and antibody carrier increases the probe to antibody ratio, which is expected to leads to better detection efficiency. The substrate used in the immunosensing is a porous 0.45 μm PVDF membrane which allows the stable immobilization of proteins. Tetraphenylporphyrin, a hydrophobic fluorescent dye, was chosen as the probe encapsulated in micelles. The block copolymer is a self synthesized α-carboxyl-ω-hydroxyl terminated Poly(ethylene oxide)-Polycaprolactone with carboxyl group on the hydrophilic end, permitting the conjugation of antibody to the micelle surface. We choose mouse IgG and its antibody anti-IgG as the pair of protein conjugates to demonstrate the immunoassay. So far, the detection limit of mouse IgG is 1.5 μg/ml (10-8 M) in this immunosensing system, which is expected to improve by modifying the system.
M.S. in Chemistry, December 2012
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- Title
- MAGNETIC RESONANCE IMAGING (MRI) OF CALIBRATION PHANTOMS AND MRI CONTRAST TRENDS IN POLYNUCLEAR CHROMIUM COMPOUNDS
- Creator
- Sun, Wanlin
- Date
- 2012-04-25, 2012-05
- Description
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This thesis is composed of two projects. The first project involves the investigation of a series of Cr+++ compounds as potential magnetic...
Show moreThis thesis is composed of two projects. The first project involves the investigation of a series of Cr+++ compounds as potential magnetic resonance imaging (MRI) contrast agents. The second part of the thesis involves collaborative work with the National Institute of Standards and Technology (NIST) in the development of an MRI calibration phantom designed to correlate data from different MRI institutions for long term studies of diseases such as Alzheimer’s. Data from the Cr+++ project indicated that these compounds show some promise for enhancement of MRI images. The second project resulted in a NIST phantom being built based partly upon data obtained here at IIT.
M.S. in Chemistry, May 2012
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- Title
- ENGINEERING 2D PHOTO-REACTING COF FOR PATTERNING AND DRUG DELIVERY
- Creator
- Chen, Kuo Hao
- Date
- 2017, 2017-07
- Description
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Covalent Organic Frameworks (COFs) are 2-dimensional polymers that exhibit rigid and large surface area as well as porous architectures....
Show moreCovalent Organic Frameworks (COFs) are 2-dimensional polymers that exhibit rigid and large surface area as well as porous architectures. Currently, COFs are tailored for gas storage applications, drug delivery, catalysis and they are used as filtering membranes for water treatment. It is well documented that at the nano/micro scale, COFs can form multi-layered architecture with respect to the basic molecular building blocks. In this picture, it is possible that the 2D intra-layer and 3D inter-layer interactions of the basic molecular units COFs may dictate the overall efficiency of the aforementioned applications. To understand the dimensionality-function relationship of COFs, we are engineering hybrid 1D-2D organic polymers. This hybrid architecture will allow us to study the propagation of energy/exciton transfer within the resulting materials among other applications such as drug delivery and light-induced nano/micro-patterning. To achieve our objectives, I exploited the photo-reacting properties of two molecular systems: The first system is used to prepare the 2D COF of interest and the other system is used to engineer a 1D crystalline solid. Although I have not tested the energy/exciton propagation with the desired material, I have successfully engineered a 1D crystalline solid and synthesized the expected 2D COFs. Using a combination of synthetic strategies, I prepared and characterized photoreacting tetra-phenyl ketone building block that was used to form the desired polymer. I have also engineered 1D needle-like crystals of bisphenyl cyclopropenone compound. Moreover, the two materials were characterized by optical and electron microscopy methods. This thesis will detail the synthesis and characterization of all precursors of the basic molecular units that were used to engineer the 1D crystalline solid and 2D COF materials. Condignly, the optical and scanning electron microscopy images highlight the microscale features of the materials of interest. I am certain that this preliminary investigation will pave the way to study the dimensionality of energy/exciton transfer and reaction propagation in the many organic materials.
M.S. in Chemistry, July 2017
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- Title
- BIOREMEDIATION VIA SILICA ENCAPSULATION
- Creator
- Li, Xiaohui
- Date
- 2011-04-25, 2011-05
- Description
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In this thesis, a new bioremediation concept is designed and implemented. Using copper (II) as a model pollutant, the concept involves the use...
Show moreIn this thesis, a new bioremediation concept is designed and implemented. Using copper (II) as a model pollutant, the concept involves the use of green algae Chlamydomonas reinhardtii to efficiently collect copper ions from the environment, followed by encapsulating copper loaded algae with silica, thus reducing the bioavailability of copper ions in the environment. A proof-of-concept was established for this concept. In Chapter 1, a brief overview of bioremediation, current state-of–the-art bioremediation methods, and the mechanisms and applications of biosorption is introduced. In Chapter 2, the potential of Chlamydomonas reinhardtii as a copper (II) absorbent is demonstrated by quantifying the copper toxicity, copper uptake rate, copper uptake capacity, copper uptake conditions and effect factors, as well as copper release process from Chlamydomonas reinhardtii. In Chapter 3, a method of encapsulating Chlamydomonas reinhardtii with silica shell using the biomimetic silicification process is described. The silica shell formation is confirmed by both scanning electron microscope (SEM) images and the fluorescence images. Finally in Chapter 4, the work in this thesis is summarized and the future research direction is discussed.
M.S. in Chemistry, May 2011
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