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Advanced Data Analysis Tools And Multi-Instrument Material Characterization, Bhupinder Singh Dec 2015

Advanced Data Analysis Tools And Multi-Instrument Material Characterization, Bhupinder Singh

Theses and Dissertations

My dissertation focuses on (i) the development of new analysis tools and methodologies for analyzing X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) data, and (ii) the comprehensive characterization of materials (nanodiamonds) using a multi-instrument approach. Chapter 1 contains (i) a discussion of the two techniques I focused on most in my work: XPS and ToF-SIMS, (ii) a discussion of the common chemometrics techniques used to analyze data from these methods, and (iii) the advantages/rationale behind the multi-instrument characterization of materials. Chapter 2 describes various good practices for obtaining reasonable peak fits in XPS, which can also …


Hand-Portable Capillary Liquid Chromatography Instrumentation, Sonika Sharma Dec 2015

Hand-Portable Capillary Liquid Chromatography Instrumentation, Sonika Sharma

Theses and Dissertations

This dissertation focuses on the development of hand-portable capillary liquid chromatography (LC) instrumentation. In this work, battery-operable nano-flow pumping systems (isocratic and gradient) were developed and integrated with portable UV-absorption detectors for capillary LC. The systems were reduced in size to acceptable weights and power usage for field operation. A major advantage of the pumps is that they do not employ a splitter, since they were specifically designed for capillary column use, thereby greatly reducing solvent consumption and waste generation. UV-absorption detectors were specifically designed and optimized for on-column detection to minimize extra-column band broadening. Initially, an isocratic nano-flow pumping …


High Flow Air Sampler For Rapid Analysis Of Volatile And Semi-Volatile Organic Compounds, Xiaofeng Xie Dec 2015

High Flow Air Sampler For Rapid Analysis Of Volatile And Semi-Volatile Organic Compounds, Xiaofeng Xie

Theses and Dissertations

Volatile and semi-volatile organic compounds are ubiquitous, and some of them are hazardous. The ability to rapidly detect and identify trace levels of them in air has become increasingly important. The conventional device used today for sampling and concentrating them in air is thermal desorption tubes filled with specific sorbents, which can only collect air samples at flow rates of 100-200 mL/min. In order to detect low concentration (ppt level) VOC compounds, long sampling time (>2 h) and sensitive detection are required. At the same time, portable instrumentation for on-site analysis has been developing rapidly. The somewhat lower performance …


Image-Charge Detection €“ Novel Instrumentation And Applications, Brandon Lee Barney Oct 2015

Image-Charge Detection €“ Novel Instrumentation And Applications, Brandon Lee Barney

Theses and Dissertations

Image-charge detection is an analytical technique in which a highly-charged particle is detected by the magnitude of the image current that it generates in a detecting electrode. This current is represented as a voltage between the charged particle and the sensing electrode. It is a single particle detection method, ideal for the analysis of large, variable mass particles such as biological cells. Some of the physical properties of Bacillus subtilis spores were explored using different applications of image-charge detection. B. subtilis is a gram-negative spore-forming bacteria that has been shown to exhibit extremophile behavior. The particular extremophile behavior that was …


Mass Spectrometry Based Proteomics And Lipidomics Studies, Huan Kang Oct 2015

Mass Spectrometry Based Proteomics And Lipidomics Studies, Huan Kang

Theses and Dissertations

Mass spectrometry has emerged as having a vital role in various applications to biochemical fields. In this thesis, we have utilized a variety of mass spectrometry techniques for both bacteriophage proteomics and colostrum and milk lipidomics studies. Our first study was the proteome characterization of Great Salt Lake bacteriophage NS01 with SDS-PAGE GEL to separate the viral proteins and high performance liquid chromatography (HPLC) coupled with an LTQ Orbitrap to identify the proteins after in-gel digestion. In this project, we have successfully identified 11 proteins with high confidence, p-values < 0.01, including coat protein gp88 with a coverage of 91% and tail protein gp86 with a coverage of 40.96%, which facilitated the classification of NS01 as a T7-like phage. Our second study was the discovery of colostrum and milk biomarkers that can be used to predict the likelihood of development of production-related metabolic diseases (PRMDs) in dairy cows through a lipidomics approach. In this study, an electrospray ionization, time-of-flight mass spectrometer was applied to lipid profiling, quantification and significant biomolecule selection. A Q-Star quadrupole, orthogonal time-of-flight mass spectrometer and an Agilent 6530 accurate-mass quadrupole/time-of flight mass spectrometer were both used for lipid biomarker fragmentation and identification. According to linear discriminative statistical modeling, three panels of biomarkers were defined. A combination of 2 milk lipid predictors, including DG18:0/18:0 and TG 18:0/18:0/18:1, provided PRMD predictions with 75.0% sensitivity at 90.0% specificity. A combination of 3 colostrum lipid predictors, including TG16:0/18:1/18:3, DG16:0/16:0 and C40H60NO, provided PRMD prediction with 90.0% sensitivity at …


Design, Fabrication, And Optimization Of Miniaturized Devices For Bioanalytical Applications, Suresh Kumar Aug 2015

Design, Fabrication, And Optimization Of Miniaturized Devices For Bioanalytical Applications, Suresh Kumar

Theses and Dissertations

My dissertation work integrates the techniques of microfabrication, micro/nanofluidics, and bioanalytical chemistry to develop miniaturized devices for healthcare applications. Semiconductor processing techniques including photolithography, physical and chemical vapor deposition, and wet etching are used to build these devices in silicon and polymeric materials. On-chip micro-/nanochannels, pumps, and valves are used to manipulate the flow of fluid in these devices. Analytical techniques such as size-based filtration, solid-phase extraction (SPE), sample enrichment, on-chip labeling, microchip electrophoresis (µCE), and laser induced fluorescence (LIF) are utilized to analyze biomolecules. Such miniaturized devices offer the advantages of rapid analysis, low cost, and lab-on-a-chip scale integration …


Peroxy Radical - Water Complexes: Their Role In The Atmosphere, Sambhav Rajendra Kumbhani Aug 2015

Peroxy Radical - Water Complexes: Their Role In The Atmosphere, Sambhav Rajendra Kumbhani

Theses and Dissertations

The importance of radical-water complexes in the atmosphere is explored in this dissertation. Radicals, although present in small concentrations in the atmosphere, play a significant role in creating and removing atmospheric pollution. As the atmosphere warms and consequently gets wetter, it is essential to understand the effects of water vapor on radical chemistry. This dissertation reports studies on the effects of water vapor on the kinetics of the self-reaction of β-hydroxyethyl peroxy radical (β-HEP), a prominent organic peroxy radical in the atmosphere. Both experimental and computational studies have been performed to examine the effects of water vapor on the kinetics …


Ribosome Component Turnover Kinetics Describes A Two-Pool Kinetic Model In Dietary Restriction That Suggests Rpl10 Is Exchanged During Ribosome Lifespan, Andrew David Mathis Aug 2015

Ribosome Component Turnover Kinetics Describes A Two-Pool Kinetic Model In Dietary Restriction That Suggests Rpl10 Is Exchanged During Ribosome Lifespan, Andrew David Mathis

Theses and Dissertations

The eukaryotic ribosome is a large molecular machine consisting of ~80 ribosomal proteins and 4 rRNAs. The 40S and 60S ribosomal subunits are assembled in the nucleolus by ~200 helper proteins then shipped into the cytoplasm or to the endoplasmic reticulum where protein translation takes place. Eventually ribosomes are removed from the cytoplasm and recycled through ribophagy, however, very is little is known about ribosomal protein exchange after assembly but before ribophagy. Using kinetic turnover measurements of ribosomal proteins and rRNA in vivo we determined ribosomal protein replacement rates are diverse suggesting ribosomal components may be replaced without destruction of …


Histone Deacetylase 6 (Hdac6) Is Critical For Tumor Cell Survival And Promotes The Pro-Survival Activity Of 14-3-3Ζ Viadeacetylation Of Lysines Within The14-3-3Ζ Binding Pocket, Jeffrey Benjamin Mortenson Jul 2015

Histone Deacetylase 6 (Hdac6) Is Critical For Tumor Cell Survival And Promotes The Pro-Survival Activity Of 14-3-3Ζ Viadeacetylation Of Lysines Within The14-3-3Ζ Binding Pocket, Jeffrey Benjamin Mortenson

Theses and Dissertations

Our understanding of non-histone acetylation as a means of cellular regulation is in its infancy. Using a mass spectrometry approach we identified acetylated lysine residues and monitored acetylation changes across the proteome as a consequence of metabolic stress (hypoxia). We observed changes in acetylation status of non-histone lysines in tumor cells. Through the use of small molecule inhibitors of histone deacetylase enzymes (HDACs) and siRNA screening identified HDAC6 as a pro-survival regulator of lysine acetylation during hypoxia. The phospho-binding protein 14-3-3ζ acts as a signaling hub controlling a network of interacting partners and oncogenic pathways. We show here that lysines …


The Synthesis And Characterization Of Ferritin Bio Minerals For Photovoltaic, Nanobattery, And Bio-Nano Propellant Applications, Trevor Jamison Smith Jul 2015

The Synthesis And Characterization Of Ferritin Bio Minerals For Photovoltaic, Nanobattery, And Bio-Nano Propellant Applications, Trevor Jamison Smith

Theses and Dissertations

Material science is an interdisciplinary area of research, which in part, designs and characterizes new materials. Research is concerned with synthesis, structure, properties, and performance of materials. Discoveries in materials science have significant impact on future technologies, especially in nano-scale applications where the physical properties of nanomaterials are significantly different than their bulk counterparts. The work presented here discusses the use of ferritin, a hollow sphere-like biomolecule, which forms metal oxo-hydride nanoparticles inside its protein shell for uses as a bio-inorganic material.Ferritin is capable of forming and sequestering 8 nm metal-oxide nanoparticles within its 2 nm thick protein shell. A …


Analytical Approaches In Investigating The Kinetics Of Water-Molecule Complexes In Tropospheric Reactions, William J. Keeton Jul 2015

Analytical Approaches In Investigating The Kinetics Of Water-Molecule Complexes In Tropospheric Reactions, William J. Keeton

Theses and Dissertations

Ozone is a heavily monitored pollutant. Ozone is not directly emitted into the atmosphere, but rather the product of chemical reactions. Ground level ozone occurs when nitrogen oxides (NOx) and volatile organic compounds (VOCs) react with each other in the presence of sunlight. The primary precursors of ozone are anthropogenically emitted, and as a result, tropospheric ozone has cost millions of dollars in damages and has hurt the health of countless people. This dissertation is a collection of work that aims to provide insight into atmospheric reactions that result in tropospheric ozone and the instrumentation to study such reactions. While …


Dna Origami Stabilized And Seeded With 4'-Aminomethyltrioxsalen For Improved Dna Nanowire Fabrication, Matthew Paul Mcdowell Jul 2015

Dna Origami Stabilized And Seeded With 4'-Aminomethyltrioxsalen For Improved Dna Nanowire Fabrication, Matthew Paul Mcdowell

Theses and Dissertations

A fast emerging technology in the microelectronics field is bottom-up self-assembly of computer circuitry. A promising method to develop nanoelectronic devices through bottom-up self-assembly is the implementation of DNA-based technologies. Using DNA to create nanoelectronic devices is advantageous because of its already well understood base-paring and annealing qualities. These base-pairing and annealing qualities can be used to design and construct DNA nanostructures called DNA origami. DNA origami are specially designed structures made from single stranded DNA. Short single stranded DNA oligonucleotides called staple strands attach to a large single stranded DNA called a DNA scaffold. DNA staple strands and DNA …


Progress Towards The Total Synthesis Of Yaku'amide A, Zhiwei Ma Jul 2015

Progress Towards The Total Synthesis Of Yaku'amide A, Zhiwei Ma

Theses and Dissertations

The synthetic progress towards yaku'amide A is described. The study leads to development of new synthetic methodologies. Base-free regioselective aminohydroxylation is convenient to deliver β-tert-hydroxyamino acids. A sequence consisting of alkylative esterification, Martin sulfurane mediated anti dehydration, a tandem azide reduction-O→N acyl transfer allows the rapid access of E- and Z-dehydroisoleucine-containing peptides from β-tert-hydroxyisoleucine derivatives. Those methods are effective in constructing complicated peptides and advanced subunits of yaku'amide A.


A Study Of Allylic Aminations As Catalyzed By Heterobimetallic Pd-Ti Complexes, Diana Lauren Ellis Jun 2015

A Study Of Allylic Aminations As Catalyzed By Heterobimetallic Pd-Ti Complexes, Diana Lauren Ellis

Theses and Dissertations

Heterobimetallic complexes present a unique approach to catalyzing challenging reactions. By having two metals in close proximity to each other, the metals are able to interact and alter their electronics in a way that simple organic ligands (carbon, nitrogen, sulfur etc.) cannot. Our studies of heterobimetallic complexes focus on a Pd–Ti complex. The complex features a dative interaction between the palladium and the titanium held together by a phosphonamide scaffold. This interaction increases the electrophilicity of the palladium and makes it a very suitable catalyst for allylic amination reactions. We have conducted extensive studies of this catalyst in allylic aminations, …


Synthesis, Rna Binding And Antibacterial Studies Of 2-Dos Mimetics And Development Of Polymer Supported Nanoparticle Catalysts For Nitroarene And Azide Reduction, Venkata Reddy Udumula Jun 2015

Synthesis, Rna Binding And Antibacterial Studies Of 2-Dos Mimetics And Development Of Polymer Supported Nanoparticle Catalysts For Nitroarene And Azide Reduction, Venkata Reddy Udumula

Theses and Dissertations

Project I 2-Deoxystreptamine (2-DOS), the most conserved central scaffold of aminoglycosides, is known to specifically recognize the 5'-GU-'3 sequence step through highly conserved hydrogen bonds and electrostatic interactions within and without the context of aminoglycosides (Figure 1a). We proposed that a novel monomeric unnatural amino acid building block using 2-DOS as a template would allow us to develop RNA binding molecules with higher affinity and selectivity than those currently available. Conjugating two or more of the monomeric building blocks by an amide bond would introduce extra hydrogen bonding donors and acceptors that are absent in natural aminoglycosides and increase specificity …


Studies On The Roles Of Translationally Recoded Proteins From Cyclooxygenase-1 And Nucleobindin Genes In Autophagy, Jonathan J. Lee Jun 2015

Studies On The Roles Of Translationally Recoded Proteins From Cyclooxygenase-1 And Nucleobindin Genes In Autophagy, Jonathan J. Lee

Theses and Dissertations

Advances in next-generation sequencing and ribosomal profiling methods highlight that the proteome is likely orders of magnitude larger than previously thought. This expansion potentially occurs through translational recoding, a process that results in the expression of multiple variations of a protein from a single messenger RNA. Our laboratory demonstrated that cyclooxygenase-3/1b (COX-3/1b), a frameshifted, intron-1-retaining, alternative splice variant from the COX-1 gene, is multiply recoded, which results in the translation of at least seven different COX-3 proteins. Two of the recoded COX-3 proteins that we identified are active prostaglandin synthases and are inhibited by non-steroidal anti-inflammatory drugs (NSAIDs). Here we …


Synthesis And Characterization Of Carbonized Poly (Divinylbenzene) Microspheres For Carbon/Nanodiamond/Polymer-Based Core-Shell Materials And Applications Of This Mixed-Mode Phase To High-Performance Liquid Chromatography, Chuan-Hsi Hung May 2015

Synthesis And Characterization Of Carbonized Poly (Divinylbenzene) Microspheres For Carbon/Nanodiamond/Polymer-Based Core-Shell Materials And Applications Of This Mixed-Mode Phase To High-Performance Liquid Chromatography, Chuan-Hsi Hung

Theses and Dissertations

This work focuses on improving the quality of carbon-based core-shell materials for high performance liquid chromatography (HPLC) via the characterization of the core materials, and also the development of chromatographic methods (separations) for them. In the early part of this work, I applied organic synthesis to make uniform, spherical poly(divinylbenzene) (PDVB) microspheres, and then carbonized them to prepare carbon core materials for core-shell particle synthesis. Here, I studied in detail the surface and material properties of these particles with multiple instruments, which allowed me to describe the physical and chemical changes that took place during each treatment. The uniform, spherical …


Immunoassays Of Potential Cancer Biomarkers In Microfluidic Devices, Jayson Virola Pagaduan Mar 2015

Immunoassays Of Potential Cancer Biomarkers In Microfluidic Devices, Jayson Virola Pagaduan

Theses and Dissertations

Laboratory test results are important in making decisions regarding a patient's diagnosis and response to treatment. These tests often measure the biomarkers found in biological fluids such blood, urine, and saliva. Immunoassay is one type of laboratory test used to measure the level of biomarkers using specific antibodies. Microfluidics offer several advantages such as speed, small sample volume requirement, portability, integration, and automation. These advantages are motivating to develop microfluidic platforms of conventional laboratory tests. I have fabricated polymer microfluidic devices and developed immunoassays on-chip for potential cancer markers. Silicon template devices were fabricated using standard photolithographic techniques. The template …


Optimization Of Nonadsorptive Polymerized Polyethylene Glycol Diacrylate As A Material For Microfluidics And Sensor Integration, Chad Rogers Mar 2015

Optimization Of Nonadsorptive Polymerized Polyethylene Glycol Diacrylate As A Material For Microfluidics And Sensor Integration, Chad Rogers

Theses and Dissertations

Microfluidics is a continually growing field covering a wide range of applications, such as cellular analysis, biomarker quantification, and drug discovery; but in spite of this, the field of microfluidics remains predominately academic. New materials are pivotal in providing tailored properties to improve device integration and decrease prototype turnaround times. In biosensing, nonspecific adsorption in microfluidic systems can deplete target molecules in solution and prevent analytes, especially those at low concentrations, from reaching the detector. Polyethylene glycol diacrylate (PEGDA) mixed with photoinitiator forms, on exposure to ultraviolet (UV) radiation, a polymer with inherent resistance to nonspecific adsorption. Optimization of the …


Fluorescence Imaging Of Analyte Profiles In An Inductively Coupled Plasma With Laser Ablation As A Sample Introduction Source, Lance Moses Jan 2015

Fluorescence Imaging Of Analyte Profiles In An Inductively Coupled Plasma With Laser Ablation As A Sample Introduction Source, Lance Moses

Theses and Dissertations

Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has risen to among the top tier techniques for the direct analysis of solid samples. However, significant problems remain that must be solved to achieve the full analytical potential of LA-ICP-MS. Inefficient conversion of aerosol to ions within the ICP or transmission through the MS interface may decrease precision, sensitivity, and/or accuracy. Although fundamental mechanisms that govern ion production and transmission have been studied extensively in solution-nebulization (SN) ICP-MS instruments, significant gaps in our understanding remain. Furthermore, it is unclear to what extent differences between the aerosols generated during SN and LA …