Physical Sciences and Mathematics Commons^™

Quantitative Analysis Of The Proteomic Selectivity Of Acidic Reductive Alkylation Of Peptides, Connor Jewell

Honors Scholar Theses

Proteome quantification is a complicated process which takes on many methods, usually involving peptide derivatization and complex mass spectral analysis. Scores of techniques have been utilized to address issues of incomplete quantification. The implementation of IPTL labeling, or isobaric peptide terminal labeling, is a recent addition to the literature, which exploits the supposedly selective labeling of N-termini of tryptic peptides from the C-termini of lysine residues due to differences in basicity. This method has been shown to improve quantitation by reducing spectral complexity and provide more accurate and reproducible results on peptide abundance. Investigations into the selectivity of terminal derivatization …

The Concentration Of Heavy Metals In Lincoln Nebraska's Tap Water, Evan Neuhaus

Honors Theses

Heavy metals are commonplace in nature, and are typically found in scarce quantities in all drinking sources. However, in high enough concentrations, they can have a myriad of negative health effects. This study seeks to find the concentrations of such metals in the Lincoln water supply utilizing the resources of the Water Center at the University of Nebraska at Lincoln. To test for discrete concentrations of trace elements, a method of using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was implemented. ICP-MS uses plasma to ionize and atomize a sample which is then filtered into a series of cones into a …

Is It Useful? Orthophosphate Mapping Of An Excavated Cellar Of A Mid 1700’S Tavern In New London Va, Thomas M. Bender, Randy Lichtenberger

Faculty Publications and Presentations

The partially backfilled cellar of Mead’s Tavern (VDHR # 015-0120) a circa 1760’s building in New London Virginia, was studied by orthophosphate (PO₄³) mapping of the recently exposed, culturally sterile, subsoil floor. Prior studies of the cellar had exposed a hearth along with features that were speculated to be wall partitions for subdivision of the cellar. The full intended purpose for those exposed features is unknown. To further probe that exposed subsoil prior to a major engineering stabilization of the tavern’s foundation, a chemical mapping of surface PO₄^3- levels in the cellar was done. The …

Non-Target Analysis Using High-Resolution Mass Spectrometry To Characterize And Remediate Urban Waters, Brian Ng

FIU Electronic Theses and Dissertations

The first part of this dissertation will focus on the development of a simple, robust online solid phase extraction liquid chromatography high resolution mass spectrometry (SPE LC-HRMS) method followed by the use of computational software workflows for non-target analysis (NTA) of environmental samples (development). The benchmarks to assess reproducibility are not well defined for non-target analysis. Parameters to evaluate analytical performance, such as accuracy, precision and selectivity, are well defined for target analysis, but remain elusive for non-target screening analysis. In this study, quality control (QC) guidelines are proposed to assure reliable data in NTA methodologies using a simple …

Utilizing Headspace Solid-Phase Microextraction For The Characterization Of Volatile Organic Compounds Released From Contraband And Its Implications For Detector Dog Training, Kelvin Joseph Frank Jr

FIU Electronic Theses and Dissertations

Improving the accuracy and reliability of odor detection dogs is of utmost importance particularly for legal reasons. Field testing in conjunction with headspace analysis of volatile organic compounds (VOCs) has in recent times allowed for these improvements, by providing scientifically based recommendations for optimum training protocols. The current project leveraged on these established capabilities to enhance three areas of odor detection: illicit drugs, explosives and mass storage devices.

With hemp being legalized under the 2018 Farm Bill, legal questions have been raised regarding a dog’s ability to ignore hemp if trained to detect marijuana, as both are types of Cannabis …

Structural Characterization Of Biomolecules Using Tandem Non- Linear And Linear Ion Mobility, Action Spectroscopy, Mass Spectrometry And Molecular Dynamics, Jacob Edward Porter

FIU Electronic Theses and Dissertations

The following thesis comprises the use of novel gas-phase spectroscopic and spectrometric techniques complemented with molecular dynamics for the structural characterization of biomolecules: from small model systems to large proteins. In particular, complementary linear and non-linear ion mobility, mass spectrometry and action spectroscopy has been applied to the separation and characterization of native and kinetic intermediate states of biomolecular ions. This suite of tools, comprising ion mobility in tandem with non-ergodic fragmentation and action spectroscopy, provided unique information on the conformational space, folding and binding dynamics of single stranded DNA, peptides, peptide-cofactor and protein systems. Theoretical modeling provided candidate structures …

Improving Thorium-230 Determination In Marine Sediment, Katherine Mateos

Independent Study Project (ISP) Collection

Our oceans are intimately related to the climate of our planet. Paleoceanographic approaches aim to study oceans through geologic time to improve models of future climate. Radioisotopes provide us with chemical tracers that help us understand change through time. The uraniumseries decay chain contains thorium-230, a decay product of uranium-234. This isotope is useful to paleoceanographers in its disequilibrium to its parent isotope and in determining the flux of sediment falling to the ocean floor. In order to use 230Th to study oceans, we must be able to accurately measure the amount of thorium in sediment samples. Thorium is found …

Determination Of Tobacco Alkaloid Enantiomers Using Reversed Phase Uplc/Ms/Ms, Huihua Ji, Ying Wu, Franklin Fannin, Lowell P. Bush

Kentucky Tobacco Research and Development Center Faculty Publications

Nʹ-Nitrosonornicotine (NNN), a carcinogenic tobacco-specific Nʹ-nitrosamine (TSNA), is on the FDA list of harmful and potentially harmful constituents (HPHCs). Nornicotine, a product of the demethylation of nicotine, is the immediate alkaloid precursor for NNN formation. Nicotine, nornicotine and NNN are optically active. The accumulation of the isomers of nicotine, nornicotine, and NNN impacts their biological activity. In this paper, we report the determination of tobacco alkaloid enantiomers (including nicotine, nornicotine, anabasine, and anatabine) in samples of different tobacco lines using a reversed phase ultra-performance liquid chromatography-tandem mass spectrometer (UPLC/MS/MS) method. Current method demonstates excellent detection capability for all alkaloid enantiomers, …

An Improved Synthesis Of Adefovir And Related Analogues, Timothy P. O'Sullivan, Et Al

Physical Sciences Publications

An improved synthesis of the antiviral drug adefovir is presented. Problems associated with current routes to adefovir include capricious yields and a reliance on problematic reagents and solvents, such as magnesium tert-butoxide and DMF, to achieve high conversions to the target. A systematic study within our laboratory led to the identification of an iodide reagent which affords higher yields than previous approaches and allows for reactions to be conducted up to 10 g in scale under milder conditions. The use of a novel tetrabutylammonium salt of adenine facilitates alkylations in solvents other than DMF. Additionally, we have investigated how …

Extraction Of Ppix From Brown Eggshells For Use In Dye-Sensitized Solar Cells, Ken Overway, Carleigh Studtmann, Taylor Varner

Chemistry Faculty Scholarship

Dye-sensitized solar cells (DSSC) are a possible alternative to traditional solar energy technologies. Organic dyes such as porphyrins seem to be an especially promising option as a sensitizer due to their characteristic Soret band and smaller Q-bands in the visible spectrum. Protoporphyrin IX (PPIX) is a naturally occurring porphyrin found in sources such as hemoglobin, chlorophyll, and brown eggshells. PPIX exhibits a typical porphyrin absorbance spectrum, and the carboxylic acid substituents make it ideal for direct attachment to the TiO₂ of the DSSC. The purpose of the research project is to extract PPIX at a high enough concentration from …

Sugar Analysis Of Mashing Process In Beer Brewing, Ken Overway, Heather Gibson

Chemistry Faculty Scholarship

In beer brewing, the mashing process produces the simple sugars that eventually become ethanol. Two important enzymes, α- and β-amylase, are most active at specific temperatures, and the mashing process tries to maximize the their efficacy. The most common sugars hydrolyzed during this process are maltose, glucose, sucrose, and fructose. Different grains require different mashing temperatures and will produce a unique amount of each sugar. Many studies have focused on the enzymatic activity to observe the mashing profile of common beer grains, such as barley or wheat. The focus of this study has been observing the enzymatic activity of barley. …

Simplifying Sample Preparation Using Fabric Phase Sorptive Extraction: Analysis Of Trace Targeted Pollutant Residues In Environmental, Biological And Food Samples, Rodolfo Mesa

FIU Electronic Theses and Dissertations

Sample preparation is an essential component of analytical methods in chemistry. It is not only necessary but also presents an opportunity to increase the effectiveness of the method significantly. There are various commercially available technologies for sample preparation, including numerous variations of LLE, SPE, and SPME. However, these technologies all present significant deficiencies, including the inability to extract directly from complex samples such as whole milk. Instrumental analysis has been improved greatly in the last two decades but still is not applicable to complex samples without sample preparation.

This work presents the theory of FPSE, including the synthesis of sol-gel …

Acid Rain Kinetics On Calcareous And Silicate Soils, Ken Overway, John Oates

Chemistry Faculty Scholarship

Calcareous, silicate, and aluminosilicate minerals are common constituents of inorganic soil. These minerals act as buffers against acid attack, either through carbonate neutralization or cation exchange. Previous studies focusing on potassium observed that cations occur in four separate phases: the solution phase, exchangeable phase, non–exchangeable phase, and the mineral phase. Each phase represents a different kinetic mechanism that is incrementally slower for cations deposited deeper in the mineral.

We have observed that when soil is exposed to acid, the pH of the soil slurry drops drastically, followed by a recovery curve on the order of seconds

to minutes. These recovery …

Extraction Of Protoporphyrin Ix For Use In Dye-Sensitized Solar Cells, Ken Overway, Carleigh Studtmann

Chemistry Faculty Scholarship

Dye-sensitized solar cells (DSSC) are a possible alternative to traditional solar energy technologies. Metal-free organic dyes such as porphyrins seem to be an especially promising option as a sensitizer due to their characteristic Soret band and smaller Q-bands in the visible spectrum. Protoporphyrin IX (PPIX) is a naturally occurring porphyrin found in sources hemoglobin, chlorophyll, and brown egg shells. PPIX exhibits typical porphyrin absorbance spectrum, and the carboxylic acid substituents make it ideal for direct attachment to the TiO2 of the DSSC. The purpose of this research is to extract PPIX at a high enough concentration from brown eggshells that …

Solid Phase Extraction Of Herbicides From Groundwater And Soils, Ken Overway, Garrett George

Chemistry Faculty Scholarship

The purpose for this experiment was to compare relative concentrations of the herbicide atrazine in soil and ground water samples. Atrazine is commonly found in groundwater and is known to be toxic to aquatic life with long lasting effects. This experiment aims to identify whether or not atrazine is present in the groundwater as well as to examine how long atrazine can persist in soil. Previous studies have shown atrazine and other related herbicides persisting with little to no degradation for up to 16 weeks. Soil and groundwater samples were obtained from a farm where atrazine is used seasonally to …

The Effects Of Rain On Elemental Transport In Soils, Laura Schoenfeld

STAR Program Research Presentations

Mini Landscape Evolution Observatory (miniLEO) is a model landscape slope composed of granular basalt used to conduct small scale experiments to more clearly understand how elemental transport occurs during simulated rain events. For this experiment, rain events occurred three times a day in two hour increments at a rate of 30 mm/hr for 14 days to determine if exchangeable ions and target elements dissolve over time. An auto sampler collected the waterseepage every half hour at the bottom of the slope of miniLEO. Each seepage sample was tested or the amount of elements present in solution using ion chromatography and …

The Creation And Evaluation Of Novel Canine Training Aids For Cocaine Using Molecularly Encapsulated Sol-Gel Polymers And An Investigation Of Canine Field Accuracy, Michelle Cerreta

FIU Electronic Theses and Dissertations

Biological detectors, such as canines, are valuable tools used for the rapid identification of illicit materials. However, recent increased scrutiny over the reliability, field accuracy, and the capabilities of each detection canine is currently being evaluated in the legal system. For example, the Supreme Court case, State of Florida v. Harris, discussed the need for continuous monitoring of canine abilities, thresholds, and search capabilities. As a result, the fallibility of canines for detection was brought to light, as well as a need for further research and understanding of canine detection. This study is two-fold, as it looks to not only …

Quantitative Analysis Of Heavy Metals In Children’S Toys And Jewelry: A Multi-Instrument, Multi-Technique Exercise In Analytical Chemistry And Public Health, Lauren E. Finch, Margot M. Hillyer, Michael C. Leopold

Chemistry Faculty Publications

For most chemistry curricula, laboratory-based activities in quantitative and instrumental analysis continue to be an important aspect of student development/training, one that can be more effective if conceptual understanding is delivered through an inquiry-based process relating the material to relevant issues of public interest and student career trajectories. Laboratory experiences that actively engage students in this manner can be difficult to identify and execute. A special topics, project-based laboratory module is presented here that utilizes multiple techniques and instruments to investigate toxic metal content (lead, cadmium, and arsenic) in children’s toys and toy jewelry. The module effectively illustrates a considerable …

Modification Of A Gas Chromatograph For Use At An Undergraduate Laboratory, Ken Overway, Andrew Veenis

Chemistry Faculty Scholarship

Gas chromatography provides chemists with a powerful method of separating and quantitating chemicals in the gas phase. Our lab recently received two PerkinElmer Arnel AutoSystem XL Gas Chromatographs from MillerCoors Brewing Company, which were designed to sample gas directly from a pressurized source. One of the gas chromatographs (GC) uses a photoionization detector (PID), a flame ionization detector (FID) and an external sulfur chemiluminescence detector (SCD). This GC was modified so that samples could be introduced by means of a syringe and a split/split-less injector. The original gas lines were entirely reconfigured to enable dual detection using the PID and …

Interactive Whiteboards And Computerized Assistance In Chemistry, Rita K. Upmacis, Elmer-Rico E. Mojico, Canan Karaalioglu

Cornerstone 3 Reports : Interdisciplinary Informatics

No abstract provided.

Soil Buffering Mechanisms, Ken Overway, Hillary Rees

Chemistry Faculty Scholarship

The effect acid rain has on soil is dependent on the mineral content. This effect varies based on the mineral systems which can buffer the pH of the soil once exposed to the acid rain. Calcareous minerals (reaction 1), silicate clays (reaction 2), and aluminosilicate clays (reaction 3) are the three mineral systems that provide soil the capacity to withstand acid attack before a major pH drop occurs. One way to differentiate between these systems could be to observe the reaction orders of the underlying mechanisms.

CaCO₃(s) 2 H⁺(aq) ⇌ Ca2+(aq) + H₂O(l) + …

Indirect Gravimetric Determination Of Waters Of Hydration, Marina C. Koether

Faculty and Research Publications

An alternate gravimetric experiment is described that can be employed in the general chemistry or the quantitative analysis laboratory course. The procedure takes less time than conventional methods and introduces students to waters of hydration and indirect determinations.

Chemistry Of Zirconia And Its Bioanalytical Applications, Oge Anazia

Masters Theses & Specialist Projects

This research studies the chemical nature of zirconia and the complex surface chemistry of zirconia in order to better comprehend its behavior under chromatographic conditions. This research shows how the physical and chemical properties of zirconia depend strongly on the thermal treatment during synthesis. The morphology of the samples was also studied. The absorption capability of Adenosine Triphosphate (ATP) on zirconia was also monitored and spectrally characterized.

The results of this research showed how the properties of zirconia vary with thermal treatment. It was observed that the zirconia prepared at a higher temperature had lower surface area, lower pore size …

A Series Of Vertically Integrated Nanotechnology Experiments For The Undergraduate Curriculum, Kevin W. Kittredge, Lesley E. Russell, Michael C. Leopold

Chemistry Faculty Publications

We have designed three nanotechnology experiments that are vertically integrated for an undergraduate chemistry curriculum. They are an evolving set of experiments for sequential courses in an undergraduate chemistry program. These experiments are designed to match the student's level of understanding for each particular course. The participating student is involved in a "research" project that progresses in both theory and experimental technique. Students benefit from these vertically integrated experiments by being involved in multiple facets of a simulated research project. This mimics a traditional research project under an advisor's supervision without the undesired drawback of an unknown outcome.

Education And Training Of Analytical Chemists: What Is Industry Looking For In A B.S. Chemist?, Julian Tyson

Chemistry Department Faculty Publication Series

No abstract provided.

Atomic Spectrometric Detectors For Flow-Injection Analysis, Julian Tyson

Chemistry Department Faculty Publication Series

The distinction between liquid chromatography and flow injection analysis is discussed in terms of the underlying concepts, the performance characteristics and the hardware involved. For the last aspect, attention is focused on the role of the detector and the development of spectroscopic detectors for these techniques is discussed. The limitations of atomic spectrometric detectors are discussed for the three most widely used techniques, flame atomic absorption spectrometry, plasma spectrometry and electrothermal atomisation atomic absorption spectrometry, and the recent literature concerned with the use of these techniques for chromatographic detectors is summarized. The use of flow-injecti�n methods to extend the capabilities …