Analytical Chemistry Commons^™

Assessment Of Catalytic Function Of Gold Nanorod-Bound Tempo Under Nir Irradiation, Kristi L. St. Clair

Honors College Theses

Gold nanoparticles are of interest to a number of fields due to their size-dependent optical properties, high stability, and large surface area. The combination of these properties allows for a variety of uses including photothermal therapy, drug delivery and catalysis. Gold nanorods (GNR) absorb light of a given wavelength which stimulates the oscillation of electrons on the surface and is known as the surface plasmon resonance effect. The localized heating of rods via irradiation may cause enhanced effectiveness of an attached organic catalyst which allows the oxidation of alcohols to occur at room temperature. Previously, similar catalytic systems required high …

Quantitative Analysis Of Bleomycin In Rat Plasma By Lc-Ms/Ms, Huawen Li

ETD Archive

Bleomycin is the most commonly used compound in its group of antineoplastic drugs. It works on tumor cells by single and double stranded DNA cleavage after its activation, in which it blocks tumor cells’ DNA replication or transcription activities to inhibit tumor cells’ growth. Bleomycin sulfate (Blenoxane) is the most popular preparation used in clinical research, and contains Bleomycin fractions of A2 and B2, which causes difficulties in quantitative analysis. This work uses the metal chelating property of Bleomycin as an advantage to simplify and improve sensitivity of existing quantitative methods. Copper was spiked in excess to plasma samples, followed …

Development Of Bioanalytical Methods For Quantitative Measurement Of Anticancer Agents, Sandeep R. Kunati

ETD Archive

The ever-growing need to develop new anticancer agents due to increased incidence of cancer and its recurrence has led to a broad range of investigational efforts in anticancer research. Drug discovery and development processes involve evaluations of pharmacokinetic and pharmacodynamic parameters of potential drug candidates in order to assess their safety, toxicity, and efficacy profiles. By providing sensitivity, assay precision, reliability, and high-throughput, mass spectrometry has become an indispensable tool in quantitative and qualitative analysis, from early-stage drug discovery and development processes to routine laboratory analysis. Development of bioanalytical methods requires knowledge of separation science with instrumentation, data interpretation and …

Oil Dries: A New Absorbent Material For Collection Of Ignitable Liquids From Semi-Porous Material, Jessica Sosa

Online Theses and Dissertations

Extraction of an ignitable liquid sample from a semi-porous surface such as concrete is especially difficult. For this purpose, two different solid oil dry absorbent materials, Instazorb and MAXXAbsorb, were researched for use of collection of ignitable liquid samples at a fire scene. These oil dries were spiked with different ignitable liquids (Coleman fuel, gasoline, kerosene, and diesel). Isolation of the ignitable liquid from the oil dry absorbent was accomplished by passive headspace isolation. Data was obtained by gas chromatography coupled with flame ionization detection (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS). Chromatograms obtained from both oil dries …

Determination Of The Oxidative Capacity Of Soot Toward Gsh And Characterization Of Soot Physicochemical Properties, Kaylee Troth

All Master's Theses

Fine atmospheric particulate matter (PM_2.5) emitted during the combustion of fossil and biomass fuels is known to adversely affect human health. While the underlying mechanisms are thought to be driven by the generation of reactive oxygen species (ROS), specific particle characteristics responsible for this detrimental effect are not well understood. In this research, the quantitative determination of the biologically relevant antioxidant, glutathione (GSH), was optimized for use as an indicator of oxidative stress to shed light on relevant particle characteristics. This was accomplished via fluorescent spectroscopy for GSH determination by way of reaction with o-phthalaldehyde (OPA), a …

An Electrochemical Characterization Of A Vanadium-Based Deoxydehydration Catalyst, Joel Eric Baker

Graduate Theses and Dissertations

Alternative methods for the conversion of polyols into olefins, be it for carbon storage or hydrocarbon fuel production, have become prevalent in today’s chemical industry. One process in particular, deoxydehydration (DODH) has been proven effective in taking sustainable biomass derivatives and converting them through the utilization of various homogenous metal catalysts. While this process may show productive yields and material conversion, it is hindered by the need of a sacrificial reductant. This makes a novel process economically unviable and relatively unused outside of scientific research. That fact begs the question: Can the process be improved? It is proposed here that …

Further Development Of Raman Spectroscopy For Body Fluid Investigation : Forensic Identification, Limit Of Detection, And Donor Characterization, Claire K. Muro

Legacy Theses & Dissertations (2009 - 2024)

The challenges to forensic body fluid analysis have placed limitations on the type of information that investigators can acquire and how that information can be collected. In recent years, Raman spectroscopy has proven itself useful for characterizing body fluids. In 2008, a large-scale investigation was undertaken to explore the use of Raman spectroscopy as a means of identifying body fluids. This work resulted in multidimensional Raman spectroscopic signatures for the five main body fluids: semen, peripheral blood, saliva, vaginal fluid, and sweat. These studies were incredibly successful and created the foundation for years of continued research. Accordingly, the studies included …

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 …

Time Travel: Scientists And Their Contributions Towards The Discoveries Of The Atom And Atomic Properties, Austin Wright

GS4 Student Scholars Symposium

The discovery of the atom and its associated components and properties paved the way for laying the foundation of chemistry related knowledge. However, the historical discoveries of each individual component are often forgotten or ignored due to the students‰Ûª innate belief of it ‰Û÷being difficult‰Ûª to remember such specific information. To assist students with grasping the properties of the atom and its components, a timeline-assisted chronology of atomic discoveries was created. Our objective is to present the scientists, with their individual contributions to atomic theory, along with the year it was discovered in an interactive manner. Using this timeline, students …

Profiling Cell Surface Sialylation And Desialylation Dynamics Of Immune Cells, Dan Wang

ETD Archive

Sialic acids (SAs) are a diverse family of naturally occurring 2-keto-3-deoxy-nononic acids that are involved in a wide range of biological processes, including early fetal development, cellular recognition, and utilization by microbes. While it is clear that cell surface SAs are highly involved in the immune system, the sialylation status of individual immune cells and functions are still unknown. In this study, I combined the newly developed LC-MS/MS methods with flow cytometry and confocal microscopy to systematically study the sialylation and desialylation dynamics of macrophages at different conditions.

First, I developed an accurate LC-MS/MS method to quantify free SA in …

Measurement Of Antioxidant Activity Toward Superoxide In Natural Waters, D. Whitney King, Emma Berger, Zachary Helm, Eleanor Irish, Kenneth Mopper

Chemistry & Biochemistry Faculty Publications

Antioxidants are a class of molecules that provide a protective function against reactive oxygen species (ROS) in biological systems by out competing physiologically important molecules for ROS oxidation. In natural waters, the reactivity of antioxidants gives an estimate of oxidative stress, and may determine the reactivity and distribution of reactive oxidants. We present an analytical method to measure antioxidant activity in natural waters through the competition between ascorbic acid, an antioxidant, and MCLA, a chemiluminescent probe for superoxide. A numerical kinetic model of the analytical method has been developed to optimize analytical performance. Measurements of antioxidant concentrations in pure and …

Kinetic Decay Of A Polymer/Ink Complex As An O2 Indicator, Becca Hoene

All Master's Theses

Indicator inks are an important part of the continued consumption of packaged goods. This thesis is focused on understanding the kinetics and reaction mechanism for a unique indicator ink that is based upon the oxidation of indigotetrasulfonate (ITS) encapsulated in the polyelectrolyte poly(diallyldimethylammonium chloride) (polyDADMAC). Sodium bisulfite (NaHSO₃) was used as the initial oxygen scavenger and to drive the reduction of the ITS. Studies were predominantly done in solution phase through the dilution of the ink systems. Fluorescence spectroscopy was the primary method used to determine the kinetic decay rates and interaction between the ITS dye molecules and …

Forensic Chemical Analysis Of Synthetic Cathinones Using Portable Mass Spectrometric Instrumentation, Caitlin N. Cain

Undergraduate Research Posters

Forensic laboratories face issues with large backlogs on evidence needing to be analyzed is due to two reasons: budgeting issues and the emergence of designer drugs. Currently, forensic laboratory directors cite that there are a shortage of scientists to deal with the yearly increase in caseloads. Additionally, designer drugs like synthetic cathinones, commonly known as “bath salts,” have increased the backlog due to the changing chemical compositions and misidentification as other compounds. Therefore, the use of a portable mass spectrometer for on-site forensic chemical analysis of synthetic cathinones would reduce the backlog of suspected controlled substances in forensic chemistry laboratories. …

The Importance Of Context: An Exploration Of Factors Influencing The Adoption Of Student-Centered Teaching Among Chemistry, Biology, And Physics Faculty, Travis J. Lund, Marilyne Stains

Department of Chemistry: Faculty Publications

Background: Research at the secondary and postsecondary levels has clearly demonstrated the critical role that individual and contextual characteristics play in instructors’ decision to adopt educational innovations. Although recent research has shed light on factors influencing the teaching practices of science, technology, engineering, and mathematics (STEM) faculty, it is still not well understood how unique departmental environments impact faculty adoption of evidence-based instructional practices (EBIPs) within the context of a single institution. In this study, we sought to characterize the communication channels utilized by STEM faculty, as well as the contextual and individual factors that influence the teaching practices …

Characterization Of Noncovalent Complexes Of Polyelectrolytes By Mass Spectrometry, Anthony J. Marino

Williams Honors College, Honors Research Projects

Various ions of poly-L-lysine and polystyrene sulfonic acid were successfully observed first within a matrix-assisted laser desorption/ionization mass spectrometer and subsequently in an electrospray ionization mass spectrometer. The successful ionization of these polymers allowed for studies to be performed on the noncovalent interactions between the two. Noncovalent interactions were effectively studied on both instruments, but further quantified using tandem mass spectrometry found within the MALDI system and ion-mobility mass spectrometry found within the electrospray ionization system. As a result of employing the use of ion-mobility, various different stoichiometries and charges of polyelectrolyte complexes could be distinguished.

Icp-Oes Analysis Of The Chemical Composition Of Hypergolic Mixtures, Monique Jones

Undergraduate Research Posters

Hypergolic mixtures involve a chemical reaction between an oxidant and a fuel source. These reactions are self-igniting and can be performed using common household materials. The ease of access to the reactants, and delayed ignition have increased the occurrence of hypergolic mixtures in arson-related crimes and incendiary devices. Currently, few chemical signatures exist to link hypergolic residues to a perpetrator. This makes it difficult to obtain forensically relevant information from evidence during an investigation. A hypergolic reaction of interest to forensic laboratories involves combustion between a glycol-based fuel source and potassium permanganate. Past studies have determined that one can distinguish …

Simultaneous Determination Of Multiple Actinide Elements In A Variety Of Soils Utilizing A Standardized Sequential Extraction Protocol, Sherry Alina Faye

UNLV Theses, Dissertations, Professional Papers, and Capstones

To obtain a better understanding of the mobility of actinide element contaminants in the environment, the association of the contaminants with specific host phases of soils and sediments must be investigated. This investigation is most commonly conducted using sequential extraction techniques that employ the selective dissolution of soil phases with increasingly aggressive chemical treatment. Though several sequential extraction studies exist in literature, conclusions cannot be made by direct comparison of data due to the lack of uniformity in the protocols used. This work aims to continue development of a standard sequential extraction protocol and expanding its capabilities to include the …

Science Classics, Mark Masthay

Chemistry Faculty Publications

An essay on the impact of the works in the Imprints and Impressions: Milestones in Human Progress, an exhibition of rare books from the collection of Stuart Rose. Exhibition was held Sept. 29-Nov. 9, 2014, at the University of Dayton.

Raman Spectroscopy For The Identification Of Body Fluid Traces : Mixtures And Contaminations, Race And Gender Differentation, Aliaksandra Sikirzhytskaya

Legacy Theses & Dissertations (2009 - 2024)

Body fluid traces are an important type of forensic evidence, which play a significant role in the reconstruction of a violent crime and often help to identify a victim or suspect based on DNA analysis. Despite a great need, there is no a single method, which could identify multiple body fluids. In addition, majority of current methods are destructive for the evidence. For about eight years, our laboratory has been working on the development of a new nondestructive method for identification of body fluid traces based on Raman microspectroscopy combined with advanced statistics. High differentiation power of the method has …

Raman Spectroscopic Analysis Of Body Fluids : Species Differentiation And The Effect Of Substrate Interference And Laser Power, Gregory Keith Mclaughlin

Legacy Theses & Dissertations (2009 - 2024)

Several recent discoveries demonstrate that Raman spectroscopy has a unique capability to characterize body fluid traces in a forensic capacity. This approach has thus garnered interest in the forensic community since 2008, when a proof of concept experiment established that blood, semen, vaginal fluid, sweat and saliva are easily differentiable through their Raman spectra. Several possible methods of identification have been described in the literature, one approach uses chemometrical models, and another applies recently formulated multidimensional Raman signatures. The analytical sampling method and the identification procedure provide several desirable traits for the field of forensic science. In particular, Raman spectroscopy …

Analysis Of Biodiesel Quality Using Reversed Phase High-Performance Liquid Chromatography, Kellyann M. Murphy

Pomona Senior Theses

The alternative fuel biodiesel is produced from the transesterification of vegetable oils or animal fat to fatty acid methyl esters. Pomona has a reactor on campus that can be used to run this reaction and produce biodiesel. The use of biodiesel has been found to lower air pollutant and greenhouse gas emissions, but can be potentially harmful to the engines if it contains impurities. This paper proposes a method using high-performance liquid chromatography to test the quality of biodiesel. This method utilizes instrumentation and materials that are available in Pomona College's Chemistry Department, requires very little sample preparation, and is …

Fractional Comparison Of Arson Accelerants Using Advanced Distillation, Sarah Clickner

Legacy Theses & Dissertations (2009 - 2024)

Detection of accelerants is often critical in proving a fire was intentional. Establishing a fire was intentionally set is not an easy task and hinges on the preservation of accelerant present in fire debris. Various accelerants have previously been studied using the advanced distillation method to get fractional composition information. The resulting fractions from advanced distillations were compared to evaporation and burn samples to determine if there were any similarities.

Development And Applications Of Ionic Liquids And Near-Infrared Multispectral Imaging Techniques, Irena Mejac

Dissertations (1934 -)

In this work, we explore novel analytical applications of Ionic Liquids and Near-infrared multispectral imaging microscopy.

Ionic liquids (ILs) belong to a group of organic salts that are liquid at room temperature and can be, due to their unique chemical and physical properties, successfully used for a variety of applications. The main goal of this study was to explore the synergistic use of ILs in chemical separations. Specifically, chiral ILs were used as novel chiral selectors for Capillary Electrophoresis and as solvents for stationary phase in Gas Chromatography. As chiral selectors IL provides baseline-separation as well as enantiomeric separation of …

Advanced Statistical Methods For Biochemical And Forensic Applications Of Raman Spectroscopy, Vitali Sikirzhytski

Legacy Theses & Dissertations (2009 - 2024)

This work is dedicated to the development and application of advanced statistical methods for biochemical and forensic applications of Raman spectroscopy. We developed a new concept of multidimensional Raman signatures for forensic identification of body fluid traces, which was successfully applied to the study of dried blood, semen, saliva, sweat and vaginal fluid stains. Several alternative advanced chemometric techniques were also successfully tested for the problems of pure body fluids discrimination and mixture analysis. Studies of body fluid mixtures with low blood and semen concentrations indicated that the detection limit of a minor contributor was as low as a few …

Optimization Of Solid-Phase Microextraction For The Determination Of Organo-Phosphorus And Organo-Chlorine Pesticide Residues In Natural Water Near Aquaculture Farms., Chan Chun Foong

Student Works (2010-2019)

The global shrimp farming industry had a rapid growth in the 1980s due to the high demand for shrimp. Apart from the destruction of mangroves and wetlands, the intensive operation of shrimp aquaculture deteriorated the water quality in the region. Variety of chemicals and biological products were used to prevent the outbreaks of diseases in the intensively managed shrimp ponds. Pesticides were used as disinfectands to kill unwanted organisms in the pond. SPME-GC-ECD method was developed for the determination of azinphos-ethyl, chlorphyrifos-methyl, diazinon, dichlorvos, endosulfan-I, endosulfan-II, endosulfan sulfate and malathion from water samples of shrimp aquaculture area in Manjung district, …

Raman Spectroscopy Of Body Fluids : A Nondestructive Identification Technique For Forensic Applications, Kelly Virkler

Legacy Theses & Dissertations (2009 - 2024)

The analysis of body fluid evidence during forensic investigations is a complicated process, yet it is a critical step in determining the key facts of a crime. There is no doubt that DNA analysis is an extremely useful tool that can identify a suspect or victim, but crime scene investigators must first locate and identify potential body fluid stains that can be collected for DNA analysis. Current screening tests are destructive to the sample and can give false positive results, so a nondestructive technique such as Raman spectroscopy, that can possibly confirm the presence of a particular fluid, could lend …

Development Of Electrochemical Sensors For Monitoring Glucose, Michael Nesbitt

Theses

The thesis focuses on evaluating calcium alginate as an immobilisation matrix for the oxidase enzyme glucose oxidase for the amperometric determination of glucose. The basic principles of enzymology and enzyme immobilisation is discussed followed by a review of a variety of first, second and third generation type enzyme electrodes. Amperometry as governed by the Cottrell equation and mass transfer models relating to amperometric electrodes are also considered.

Bovine serum albumin (BSA / GOx) enzyme electrode system was employed as a model to evaluate a calcium alginate immobilisation technique for glucose oxidase. The principal methods employed for enzyme immobilisation were:

• …

The Activity Of Silicon Carbide Particles In Al-Based Metal Matrix Composites Revealed By Scanning Electrochemical Microscopy, David O. Wipf, L. Díaz-Ballote, L. Veleva, M. A. Pech-Canul, M. I. Pech-Canul

CAS Publications

Scanning electrochemical microscopy (SECM) is used to image variations in electrochemical activity over the surface of an aluminum-based metal matrix composite (MMC) in contact with buffered or unbuffered neutral solutions. The composite consists of an Al - 13.5% Si - 9% Mg alloy matrix and reinforcing silicon carbide particles (SiC_p). Feedback mode SECM imaging using ferrocenemethanol as a redox mediator in 0.1 M NaCl solution and in buffer solution (pH 6.8) revealed that the SiC particles are electrochemically active. The data suggest that the electronic conductivity at these sites is higher than that of the Al₂O …

A Kinetic Analysis Of The Iodination Of Pyruvic Acid And Pyruvate Esters, Mohamed M. Fahmi Hegazi

All Master's Theses

In the present work the relative rates of iodination of pyruvic acid and ethyl and methyl pyruvate have been compared at 25.0° C. These studies allow the determination of the respective free energies of activation for these processes. Measurements have also been carried out at various temperatures to determine the enthalpies and entropies of activation for the spontaneous and base catalysed iodinations of these pyruvate systems. The present thesis also includes a comparison of the solvent deuterium isotope effects associated with the spontaneous rate of iodination of pyruvic acid and the alkyl pyruvates. Also, the catalytic rate coefficients associated with …

Acid-Base Catalysis Of The Enolization Of Acetone, Janet Louise Larson

Undergraduate Honors Theses

Measurements are reported on the rate of iodination of acetone at 25°c in arsenate, phosphate, and diethylmalonic acid buffers at a constant ionic strength of 0.2. Unlike earlier results which indicate that in acetic acid buffer the expression for the reaction velocity contains an appreciable kinetic term involving the product of the concentrations of acid and anion, it has been found from the present work that such a term is experimentally immeasurable for the above mentioned buffers. This finding coupled with the relatively powerful catalysis by the phosphate and arsenate dianions could imply the simultaneous participation of these species in …