Analytical Chemistry Commons^™

Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry Analysis Of Lower Pecos Rock Paints And Possible Pigment Sources, Jon Russ, Kaixuan Bu, Jeff Hamrick, James V. Cizdziel

Master of Science in Analytics (MSAN) Faculty Research

Chemical analyses of prehistoric rock paints from the Lower Pecos Region of southwestern Texas were undertaken using laser ablation-inductively coupled plasma-mass spectrometry. This technique allowed us to measure the chemical composition of the paint pigments with minimal interference from a natural rock coating that completely covers the ancient paints. We also analyzed samples representing potential sources of paint pigments, including iron-rich sandstones and quartzite from the study area and ten ochre samples from Arizona. Cluster analysis, principle component analysis and bivariate plots were used to compare the chemical compositions of the paint and pigment sources. The results indicate that limonite …

Integrated Approach For Low-Cost And Sensitive Multiplex Pathogen Detection On 3d Paper-Based Microfluidic Devices, Alejandra Valadez, Huan Hu, Xiujun James Li

COURI Symposium Abstracts, Summer 2012

Recently, pathogenic microorganisms have aroused wide public concern for their potential to cause serious diseases in humans, animals and agricultural crops. Although DNA microarrays are commonly used for pathogen detection, the approach is sophisticated, time-consuming and requires expensive equipment, limiting its application in resource-poor settings. Herein we present a novel, low-cost, paper-based microfluidic approach for multiplexed DNA detection of Giardia Lamblia, S. aureus, and Entamoeba, by “on-chip” isothermal DNA amplification and hybridization. Paper-based microfluidics offers a novel, sensitive and low-cost alternative for Point-of-Care Diagnostics for the Developing Countries. The project described utilizes Loop-mediated Isothermal Amplification (LAMP), a novel isothermal DNA …

Characterization Of Polymeric Phthalocyanine Nanoparticles Using Dynamic Light Scattering Laser, Satish Kumar Murarishetty

All Capstone Projects

The objective of this study is to use DLS (Dynamic Light Scattering) to analyze polymeric copper phthalocyanine nanoparticles (CuPcNPs). CuPcNPs are synthesized in order to facilitate drug penetration of bacterial biofilms for the treatment of chronic wounds. Microorganisms that reside inside the biofilms of chronic wounds are very resistant to any kind of treatment, even to the host’s own immune system. Therefore we have proposed an alternative method to destroy the microorganisms existing within the biofilms. Photodynamic anti-bacterial chemotherapy (PACT) has received much attention for the past decade due to the multi-drug resistant strands. PACT uses photons, a photosensitizer, and …

Nanoencapsulated Copper Pthalocyanine As Photodynamic Antimicrobial Chemotherapy, Prathima Arrabelly

All Capstone Projects

The growing resistance developed by microbes towards antimicrobial agents has driven our focus on developing alternative treatment modalities such as Photodynamic antimicrobial chemotherapy (PACT). It would be difficult for the microbes to develop resistance towards singlet oxygen generated during the PACT process. Photosensitizers are the vehicles of the transfer and translation of light energy into a type II chemical reaction (singlet oxygen generation) in photodynamic antimicrobial chemotherapy. PACT is proposed as a potential, low cost approach to treatment of locally occurring infection.

Photodynamic inactivation (PDI) of Escherichia coli and Staphylococcus aureus has been studied in cultures treated with photoactivated copper …

Nano Encapsulated Drug Delivery For Biofilms, Arunakanth Chavala

All Capstone Projects

Biofilms are now considered ubiquitous in the natural world. Bacterial biofilms have been observed to be extremely heterogeneous, both structurally and with regard to the physiology of the bacterial cells within them. The prevailing conceptual model depicts bacterial biofilms as being made up of microcolonies, which serve as the basic unit of the greater biofilm structure. A major concern with this approach is the frequently observed development of resistance to antimicrobial compounds. A number of elements in the process of biofilm formation have been studied as targets for novel drug delivery technologies. The present study aimed to penetrate biofilm by …

Analysis Of Barbiturates By Gc/Ms, Hplc And Chemical Ionization, Deepthi Ravipati

All Capstone Projects

Barbiturates are derivatives of barbituric acid. They act as central nervous depressants. These drugs are frequently used as sedatives or anesthetics. It is a simple and reproducible method for the analysis of barbiturates.

Usage of these drugs is increased in recent days and the analysis of barbiturates by GC/MS is very fast. As they are used as sedatives their usage has been increased to relieve the stress. But the over usage of these drugs may lead to death. Different barbiturates like phenobarbital, pentobarbital can be analyzed by their molecular weights. Because of the over usage of the drugs the interest …

Nanoparticlated Drug Delivery System For Vitreous Humor, Kartheek K. Suragoni

All Capstone Projects

The purpose of this study is to develop a unique nanoparticulated system that has the capability of providing sustained drug delivery into the eyes. In ophthalmic preparations, poor ocular drug delivery of ocular dosage form is due to the production of tears and impermeability through corneal epithelium. The usage of liposomes in ophthalmic disorders shows promising results in ocular drug delivery. Liposomes are bilayered, microscopic vesicles surrounded by the aqueous compartments. Liposomes have the ability to encapsulate both hydrophilic and hydrophobic drugs. This unique property of liposomes helps in delivering the drug at specific site. This invention involves three major …

Spectroscopic Characterization Of Dissolved Organic Matter: Insights Into Composition, Photochemical Transformation And Carbon Cycling, John Robert Helms

Chemistry & Biochemistry Theses & Dissertations

This dissertation explores processes affecting the composition of dissolved organic matter (DOM) and how DOM composition changes in sunlit surface waters and in the dark interior ocean. Simulated solar irradiations were used to investigate the impact of photochemistry on terrestrial waters and deep ocean DOM. The photochemically mediated processes observed in Dismal Swamp samples included (i) light induced flocculation of up to 12% of the organic matter and 84% of the dissolved iron originally present; (ii) 74-88% mineralization of dissolved organic carbon (DOC) and 95-99% bleaching of chromophoric DOM (CDOM) during 110 days of irradiation; and (iii) nearly complete loss …

Nih Shift Literature Search, Nicole Owens

All Capstone Projects

The NIH shift is a chemical shift of substituents in aromatic hydroxylation reactions. The substituents that undergo this shift are hydrogen, halogens, acyl and alkyl groups. It is an important aspect that is a requirement in the hydroxylation of aromatic compounds by monooxygenase enzymes.

The NIH shift or the National Institute of health shift gets its name from the founders of this mechanism. The National Institute of Health was the first to observe this phenomenon in there studies and are the first to report this chemical shift.

Simple Analysis And Possible Solutions Of The Unusual Interfacial Reactions In Li-S Batteries, Xin-Ping Ai, Yu-Liang Cao, Han-Xi Yang

Journal of Electrochemistry

Rechargeable Li-S batteries are a promising power source with realizable energy densities several times higher than current Li-ion batteries. However, the capacity utilization and cycling stability of the existing Li-S technologies are still insufficient for battery applications. The causes for the electrochemical instability of this redox system arise probably from the changes in the surface structures and electrochemical microenvironments of the Li anode and sulfur cathode during charge-discharge reactions, which includes the frustrated electron transfer in the sulfur-carbon interface, the dissoluble diffusion of the polysulfide intermediates, and the shuttle reaction inbetween the sulfur and Li electrodes. To deal with these …

Detection Of Pml/Rarî± Fusion Gene Using Gold Nanopaticles Modified Electrode By Chronocoulometry, Li-Man Wang, Li-Qing Lin, Shao-Huang Weng, Xin-Hua Lin, Yuan-Zhong Chen

Journal of Electrochemistry

A gold nanoparticles modified electrode was prepared by electrodeposition at constant potential. The sulfydryl modified probe was immobilized onto surface of gold nanoparticles via Au-S covalent bond and hybridized with complementary target DNA sequences, then the DNA sensor was fabricated for the detection of PML/RARα fusion gene by chronocoulometry in acute promyelocytic leukemia (APL). Scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS) were used to characterize the surface morphology of gold nanoparticles and the constructing process of sensor. With hexaammineruthenium(Ⅲ) chloride (RuHex) as a novel electrochemical indicator, the chronocoulometric DNA biosensor was employed to monitor artificial APL PML/RARα fusion …

Concentration Effects And Ion Properties Controlling The Fractionation Of Halides During Aerosol Formation, Marcelo I. Guzman, Richa R. Athalye, Jose M. Rodriguez

Chemistry Faculty Publications

During the aerosolization process at the sea surface, halides are incorporated into aerosol droplets, where they may play an important role in tropospheric ozone chemistry. Although this process may significantly contribute to the formation of reactive gas phase molecular halogens, little is known about the environmental factors that control how halides selectively accumulate at the air-water interface. In this study, the production of sea spray aerosol is simulated using electrospray ionization (ESI) of 100 nM equimolar solutions of NaCl, NaBr, NaI, NaNO(2), NaNO(3), NaClO(4), and NaIO(4). The microdroplets generated are analyzed by mass spectrometry to study the comparative enrichment of …

Cloning And Characterization Of Sas0754, A Hypothetical Protein From Community Associated Staphylococcus Aureus, Unknown Unknown

Symposium 2012

Community associated Staphylococcus aureus (strain MSSA476) is a gram positive cocci capable of infecting many different parts of the body and known to cause serious infections that can be fatal, such as bacterial arthritis and acute endocarditis. To find effective ways of fighting against CA-MRSA strains we must learn more about their ability to infect. The focus of this study was cloning and characterization of a protein referred to as SAS0754. The size of SAS0754 is 340 amino acids and the gene sequence is 1023 nucleotides. The hypothetical function of this protein is that it is an extracellular matrix binding …

A Convenient Synthesis Of 2,6-Dichlorohomonicotinic Acid, Chase Buchanan, Richard W. Fitch

Symposium 2012

In our synthetic efforts toward the alkaloid phantasmidine, we required a convenient source of the title compound. Herein, we describe a short synthesis of 2,6-dichlorohomonicotinic acid by direct allylation of 2,6-dichloropyridine with LDA/allyl chloride, followed by permanganate oxidation of the side chain [figure1]. Yields for the allylation are high, while permanganate oxidation required more adjustment. Successful conditions require the modest acidification of the mixture with acetic acid and cleanup by acid base workup. No chromatography is needed.

Convenient Parallel Synthesis Of Alkyl- And Aryl-S-Tert-Butyl Thiothers, Rebecca Norcross, Jessica Stanfield, Richard W. Fitch

Symposium 2012

While preparing novel cysteine derivatives as oxidation catalysts, we needed S-tert-butylcysteine. We also examined acid-promoted tert-butylation of thiols using tert-butanol as reagent and solvent. While cysteine and aminoethanethiol work well using tBuOH in 4M HCl, other thiols fail in the aqueous environment and aerobic conditions. We examined a variety of aliphatic and aromatic thiols in tBuOH with H2SO4 catalysis and found that argon sparging and the use of 1 eq of acid led to good yields in a parallel format.

Enhancement In Degradation Of Environmental Pollutants: Fenton Degradation Of 2,4,6-Trinitrotoluene And Photodegradation Of Deepwater Horizon Crude Oil, Sarah M. King

LSU New Orleans Theses and Dissertations

Pollution poses serious threats to both the environmental and the organisms that depend on their environment for survival. Due to the toxicity of most contaminants, there is a dire need for remediation of polluted sites. Remediation studies were conducted on two high priority pollutants: 2,4,6-trinitrotoluene (TNT) and crude oil.

TNT was the most common explosive used in the 20^th century. Continuous contamination has resulted in an urgent need for remediation. Fenton reagent provides an advanced oxidation process that is capable of remediating recalcitrant explosives, such as TNT. One drawback of Fenton chemistry is that the reaction requires acidic pH …

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 …

The Analysis Of Protein-Bound Thiocyanate In Plasma Of Smokers And Non-Smokers As A Marker Of Cyanide Exposure, Stephanie L. Youso, Gary A. Rockwood, Brian A. Logue

Chemistry and Biochemistry Faculty Publications

When cyanide is introduced into the body, it quickly transforms through a variety of chemical reactions, normally involving sulfur donors, to form more stable chemical species. Depending on the nature of the sulfur donor, cyanide may be transformed into free thiocyanate, the major metabolite of cyanide transformation, 2-amino-2-thiazoline-4-carboxylic acid or protein-bound thiocyanate (PB-SCN) adducts. Because protein adducts are generally stable in biological systems, it has been suggested that PB-SCN may have distinct advantages as a marker of cyanide exposure. In this study, plasma was analyzed from 25 smokers (chronic low-level cyanide exposure group) and 25 non-smokers for PB-SCN. The amount …

Synthesis, Modification, And Characterization Of Spherical Sba-15 Ordered Mesoporous Silica And Evaluation In High Performance Liquid Chromatography, Alexander P. Giaquinto

Seton Hall University Dissertations and Theses (ETDs)

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Analysis Of Street Drugs Using Comprehensive Two Dimensional Gas Chromatography Coupled With Time Of Flight Mass-Spectrometry, Brian B. Barnes

Seton Hall University Dissertations and Theses (ETDs)

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