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Legacy Theses & Dissertations (2009 - 2024)

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Articles 181 - 210 of 218

Full-Text Articles in Chemistry

The Analytic Reconciliation Of Classic Mayan Elite Pottery : Squaring Pottery Function With Form, Adornment, And Residual Contents, Jennifer Ann Loughmiller-Newman Jan 2012

The Analytic Reconciliation Of Classic Mayan Elite Pottery : Squaring Pottery Function With Form, Adornment, And Residual Contents, Jennifer Ann Loughmiller-Newman

Legacy Theses & Dissertations (2009 - 2024)

This dissertation presents a multidisciplinary means of determining the actual content (foodstuff, non-foodstuff, or lack of contents) of Classic Mayan (A.D. 250-900) vessels. Based on previous studies that have identified the residues of foodstuffs named in hieroglyphic texts (e.g. cacao), this study is designed to further investigate foodstuff residues in the elite vessels indicated by text or image to contain those residues, and the methods employed for residue characterization. Prior to studies utilizing residue analysis, the content of Classic Maya vessels largely had long been inferred largely by ethnographic analogy, associating specific vessel forms with specific uses based on ethnographic …


Inhibition Of Glutamate Receptors By Constructing Bipartite Rna Aptamers, Jeffrey Hebert Jan 2012

Inhibition Of Glutamate Receptors By Constructing Bipartite Rna Aptamers, Jeffrey Hebert

Legacy Theses & Dissertations (2009 - 2024)

The relationship of excessive activity of AMPA-type glutamate receptors, and cell death, has long provided researchers a means of investigating neurodegenerative disorders, such as Parkinson's Disease (PD) and amyotrophic lateral sclerosis (ALS). Inhibitors of AMPA receptor channels, including chemical and nucleic acid molecules such as RNA aptamers, have served as potential therapeutic agents and treatment of neurodegenerative disorders. In this study, building bipartite aptamers to enhance inhibitory potency, as compared with a monomeric aptamer of AMPA receptor, is described. An enhanced potency is due, at least in part; to the proximity effect in bipartite structures or binding of a monomeric …


A Novel Fabrication Technique For Three-Dimensional Nanostructures, Ravi Kiran Bonam Jan 2012

A Novel Fabrication Technique For Three-Dimensional Nanostructures, Ravi Kiran Bonam

Legacy Theses & Dissertations (2009 - 2024)

Three dimensional micro- and nano-structures are commonly used in the field of Photonics, Optoelectronics, Sensors and Biological applications. Although numerous physical models are developed, a major challenge has been in their fabrication which is commonly limited to conventional layer-by-layer techniques. In this dissertation, a novel method for fabricating three dimensional structures using Electron Beam Lithography (EBL) will be presented.


Statistical Analysis Of Gasoline As An Accelerant Using Principal Component Analysis, Carolyn Frantz Jan 2012

Statistical Analysis Of Gasoline As An Accelerant Using Principal Component Analysis, Carolyn Frantz

Legacy Theses & Dissertations (2009 - 2024)

Arson is one of the most difficult crimes to investigate, as much of the physical evidence is destroyed by the fire. Evidence of an accelerant at a scene is often vital in determining whether a fire was intentional or accidental. Gasoline is one of the most commonly used accelerants, due to its wide availability and low cost. Neat gasoline samples were analyzed by gas chromatography/mass spectrometry (GC/MS) to identify the components present in each gasoline and differentiate between gasoline samples based on their seasonal blend and grade. Advanced distillations were executed to compare regular and premium grade gasolines and determine …


Mechanism Of Inhibition Of The Glua2 Receptors By N-3 Derivatives Of 2,3-Benzodiazepines With C-4 Methyl Group, Congzhou Wang Jan 2012

Mechanism Of Inhibition Of The Glua2 Receptors By N-3 Derivatives Of 2,3-Benzodiazepines With C-4 Methyl Group, Congzhou Wang

Legacy Theses & Dissertations (2009 - 2024)

α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors are one of the three subtypes of ionotropic glutamate receptors. AMPA receptors mediate fast synaptic neurotransmission in the central nervous system (CNS). Over-activation of calcium permeable AMPA receptors causes intracellular calcium overload, which leads to neurodegeneration and cell death. As such, AMPA receptors have been implicated in a number of neurological disorders and diseases, such as epilepsy, amyotrophic lateral sclerosis (ALS), and Parkinson's disease. 2,3-Benzodiazepine derivatives (or GYKI compounds) are a group of structurally similar compounds synthesized as inhibitors of AMPA receptors, and they have been used as potential drug candidates for the treatment of various …


Structural And Thermodynamic Anaylsis Of Self-Assembled Dna Cross-Tiles, Lauren Hakker Jan 2012

Structural And Thermodynamic Anaylsis Of Self-Assembled Dna Cross-Tiles, Lauren Hakker

Legacy Theses & Dissertations (2009 - 2024)

A thermodynamic and structural analysis of DNA nanostructures was performed, following the replacement of the unpaired thymine bases within a central loop to determine their effect on the self-assembly process. Specifically this study focused on DNA cross-tile nanostructures. Self-assembly of DNA cross-tiles occurs by means of Watson-crick base-pairing interactions between designed single-stranded DNAs from which lattice structures assemble through sticky-end cohesion. These cross-tile structures were constructed from nine single-stranded DNAs and consisted of a central loop containing 16 unpaired thymine bases, four shell strands, and four arms. Modifications were introduced to replace the central unpaired thymine base loop. The modifications …


Interactions Of The Human Immunodeficiency Virus Type 1 Nucleocapsid Protein With Non-Hiv-Derived Nucleic Acids : Implications For The Viral Replication Cycle, Abhijit Padmakar Jadhav Jan 2012

Interactions Of The Human Immunodeficiency Virus Type 1 Nucleocapsid Protein With Non-Hiv-Derived Nucleic Acids : Implications For The Viral Replication Cycle, Abhijit Padmakar Jadhav

Legacy Theses & Dissertations (2009 - 2024)

During attempts to develop aptamers that bind to the nucleocapsid protein of HIV-1 (i.e. NCp7) with high affinity, a heretofore unreported property of the protein--the ability to mediate degradation of nucleic acids, was discovered. Using λ DNA as a model nucleic acid system, it was shown that NCp7-mediated degradation of nucleic acids is non-specific, depends on incubation time, the concentration of NCp7, and the presence of divalent and monovalent cations. It was further demonstrated that degradation can be abrogated if NCp7 is pre-incubated with NCp7-inhibitors. Lyophilization of NCp7 can induce irreversible changes in its secondary structure that result in loss …


Fractional Comparison Of Arson Accelerants Using Advanced Distillation, Sarah Clickner Jan 2012

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.


The Application Of Raman Spectroscopy As A Confirmatory Blood Test In The Presence Of Sodium Hypochlorite Cleaners In In Comparison With Presumptive Blood Tests, Aliea Anoshaa Afnan Jan 2012

The Application Of Raman Spectroscopy As A Confirmatory Blood Test In The Presence Of Sodium Hypochlorite Cleaners In In Comparison With Presumptive Blood Tests, Aliea Anoshaa Afnan

Legacy Theses & Dissertations (2009 - 2024)

Popular presumptive tests for blood include: Luminol, tetramethylbenzidine (TMB), leucomalachite green (LMG), phenolphthalein, and Hemastix® [3]. These presumptive tests have been reviewed with respect to their sensitivity, specificity, and DNA degradation. In this study, the aforementioned presumptive tests were subjected to bloodstains deposited on cotton contaminated with all-purpose bleach and compared with Raman spectroscopy as an application of a confirmatory blood test. Samples were tested for interference with the all-purpose bleach to determine the selectivity of the presumptive tests. Tetramethylbenzidine, leucomalachite green, and phenolphthalein all yielded inconclusive results when applied to a contaminated sample. Luminol and Hemastix® yielded a positive …


Amyloid Fibril Polymorphism : Structure, Supramolecular Chiraliy And Spontaneous Interconversion, Dzmitry Kurouski Jan 2012

Amyloid Fibril Polymorphism : Structure, Supramolecular Chiraliy And Spontaneous Interconversion, Dzmitry Kurouski

Legacy Theses & Dissertations (2009 - 2024)

Specific protein aggregation has been linked to more than 25 severe human maladies including prion, Alzheimer's, and Parkinson's diseases. These important malfunctions are often referred to as 'conformational' disorders and result from the conversion of a normal isoform of a protein into a specific b-sheet rich polymeric amyloid form. This work elaborates a comprehensive characterization of amyloids and dedicated to the investigation of the fibril polymorphism using advanced microscopic tools, such as Atomic Force and Scanning Electron microcopies, together with several vibrational spectroscopy techniques, such as Raman, Infrared and Vibrational Circular Dichroism. A new type of protein folding-aggregation phenomenon, spontaneous …


Investigation Of Titanium Nitride As Catalyst Support Material And Development Of Durable Electrocatalysts For Proton Exchange Membrane Fuel Cells, Bharat Avasarala Jan 2011

Investigation Of Titanium Nitride As Catalyst Support Material And Development Of Durable Electrocatalysts For Proton Exchange Membrane Fuel Cells, Bharat Avasarala

Legacy Theses & Dissertations (2009 - 2024)

The impending energy and climatic crisis makes it imperative for human society to seek non-fossil based alternative sources for our energy needs. Although many alternative energy technologies are currently being developed, fuel cell technology provides energy solutions, which satisfy a wide range of applications. But the current fuel cell technology is far from its target of large scale commercialization mainly because of its high cost and poor durability. Considerable work has been done in reducing the cost but its durability still needs significant improvement. Of the various materials in a PEM fuel cell, the degradation of electrocatalyst affects its durability …


Significance Of Hno3 Acid Photolysis On Surfaces In Tropospheric Chemistry, Honglian Gao Jan 2011

Significance Of Hno3 Acid Photolysis On Surfaces In Tropospheric Chemistry, Honglian Gao

Legacy Theses & Dissertations (2009 - 2024)

The reactive nitrogen trace gases (NOy) including nitrogen oxides (NOx) and their secondary products are known to cause ground-level ozone pollution, photochemical smog, acid deposition, and overall air quality degradation. NOx was believed to be permanently removed from the atmospheric by HNO3 formation and deposition. However, our laboratory experimental results show that HNO3 can be remobilized back to photochemically labile HONO and NOx (re-NOx-ification). We have verified and quantified HONO and NOx production from the photolysis of HNO3 on various surfaces, including Pyrex, leaves of plants, and other environmentally relevant …


Distributions And Sources Of Hono In The Rural Troposphere, Ning Zhang Jan 2011

Distributions And Sources Of Hono In The Rural Troposphere, Ning Zhang

Legacy Theses & Dissertations (2009 - 2024)

Nitrous acid (HONO) is an important precursor of hydroxyl radical and plays an important role in the terrestrial boundary layer photochemistry. However, there are still many unknowns regarding HONO chemistry such as formation mechanisms and distributions in the troposphere, especially in rural and remote environments. In this research, we presented the first vertical concentration profiles of HONO in the troposphere, measured on a small aircraft platform. The HONO mixing ratios ranged from 4 to 17 pptv in the free troposphere and from 8 to 74 pptv in the rural boundary layer. The HONO distribution patterns were strongly correlated to the …


Single Cell Analysis For The Characterization Of Cell Populations Using A Live Cell Array, Maureen Ann Walling Jan 2011

Single Cell Analysis For The Characterization Of Cell Populations Using A Live Cell Array, Maureen Ann Walling

Legacy Theses & Dissertations (2009 - 2024)

In the past decade, the shift from whole cell population analyses towards single cell measurement methods and techniques is based on experimental results that reveal significant levels of non-genetic heterogeneity in clonal cell populations. This heterogeneity manifests in multiple aspects of cell activity and is, in part, a result of stochastic noise in processes leading to gene expression, namely transcription and translation. The growing understanding of this occurrence has led to the development of methods to monitor and analyze heterogeneity for a more thorough description of cell populations and overall activity.


New Photoluminescent Copper(I) Complexes : Impact Of Bridging Carboxylates On Solid-State Structures And Photophysical Properties, Oleksandr Hietsoi Jan 2011

New Photoluminescent Copper(I) Complexes : Impact Of Bridging Carboxylates On Solid-State Structures And Photophysical Properties, Oleksandr Hietsoi

Legacy Theses & Dissertations (2009 - 2024)

Polynuclear copper(I) carboxylates exhibiting rich luminescent properties and a remarkable structural diversity have been the main focus of this investigation. In spite of the well-developed methods of copper(I) carboxylates synthesis, only a handful of complexes have been crystallographically characterized prior to our work. Notably, they all demonstrate different structural arrangements in the solid state. This dissertation describes the work that has been carried out towards the synthesis of new copper(I) carboxylates, the study of their molecular and solid-state structures, and their solid-state photoluminescent (PL) properties. In this work, we have prepared a series of new copper(I) carboxylates of the general …


Structural Interactions And Dynamics Of Disease Related Proteins By Using Nmr Spectroscopy, Shadakshara Swamy Puttamadappa Jan 2011

Structural Interactions And Dynamics Of Disease Related Proteins By Using Nmr Spectroscopy, Shadakshara Swamy Puttamadappa

Legacy Theses & Dissertations (2009 - 2024)

Nuclear Magnetic Resonance (NMR) is a powerful spectroscopic technique to study the structure, molecular interactions, and dynamics of proteins. Modern NMR instrumentation, advancements in experimental techniques and revolutionary developments in recombinant DNA technology have made NMR a versatile and very convenient tool for biomolecule characterization.


In-Cell And In Vitro Studies Of Disease Related Protein-Protein Interactions Using Nmr-Spectroscopy, Andres Yudiel Maldonado Jan 2011

In-Cell And In Vitro Studies Of Disease Related Protein-Protein Interactions Using Nmr-Spectroscopy, Andres Yudiel Maldonado

Legacy Theses & Dissertations (2009 - 2024)

The receptor for advanced glycation end products (RAGE) is a multiligand cell surface macromolecule that plays a central role in the etiology of diabetes, inflammation, and neurodegeneration. The cytoplasmic domain of RAGE, ctRAGE, is critical for RAGE-dependent signal transduction. As the most membrane proximal event, mDia1 binds to ctRAGE and is essential for RAGE ligand-stimulated phosphorylation of AKT and cell proliferation/migration. We show that ctRAGE contains an unusual alpha-turn that mediates the mDia1-ctRAGE interaction and is required for RAGE dependent signaling. The results establish a novel mechanism through which an extracellular signal initiated by RAGE ligands regulates RAGE signaling in …


A Biophysical Study Of Small Molecule-Nucleic Acid Interactions, Rajiv Thapa Jan 2011

A Biophysical Study Of Small Molecule-Nucleic Acid Interactions, Rajiv Thapa

Legacy Theses & Dissertations (2009 - 2024)

Nucleic acids are the biomolecules that encodes all the genetic information necessary for cellular metabolism. Binding of small molecules to DNA or RNA can alter their structures; perturb their functions as well as interactions with proteins and other ligands. This thesis focuses on the biophysical study of the interactions of three planar compounds with TAR 32 DNA (32 ntds DNA in HIV-1 LTR, Figure. The purpose for this study is to understand the binding modes of some of the potential drug target compounds, which will be useful for future rational drug design strategies.


Developing Dimetal Paddlewheel Complexes For Catalytic Applications, Margaret E. Napier Jan 2011

Developing Dimetal Paddlewheel Complexes For Catalytic Applications, Margaret E. Napier

Legacy Theses & Dissertations (2009 - 2024)

Although there are countless examples of rhodium-catalyzed organic reactions in the chemical literature, the field continues to develop at a steady pace, as focus shifts taking advantage of economy of resources while maintaining efficiency of the catalytic reactions. The work presented is separated into three chapters, with each describing a specific approach to the development of new materials which can provide either a direct economy of resources and reagents or can be used for heterogenization of catalytic systems.


Single-Source Precursors For Heterometallic Materials, Lan Ngoc Huynh Jan 2011

Single-Source Precursors For Heterometallic Materials, Lan Ngoc Huynh

Legacy Theses & Dissertations (2009 - 2024)

ABSTRACT


Advanced Statistical Methods For Biochemical And Forensic Applications Of Raman Spectroscopy, Vitali Sikirzhytski Jan 2011

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 …


Synthesis And Characterization Of Diallylic Polysulfanes And Study Toward The Synthesis Of Thiarubrine E, Kai Wang Jan 2011

Synthesis And Characterization Of Diallylic Polysulfanes And Study Toward The Synthesis Of Thiarubrine E, Kai Wang

Legacy Theses & Dissertations (2009 - 2024)

Garlic oil contains diallyl polysulfanes as major components, which have been used as environmentally benign bird repellants and nematicides. While previous studies found that the biological activity of polysulfanes increases with numbers of sulfur atoms, higher diallyl polysulfanes are currently unavailable. A simple approach was developed, using liquid sulfur as a reagent, to the synthesis of diallyl polysulfanes containing chains of more than 20 sulfur atoms. This method was successfully applied to other diallylic disulfides and to garlic oil to give new families of polysulfanes. Some diallyl polysulfanes were isolated in a pure form by preparative high performance liquid chromatography …


Interactions Of Hydrogen Peroxide And Oxalic Acid On Ice Films, Hui Yan Jan 2011

Interactions Of Hydrogen Peroxide And Oxalic Acid On Ice Films, Hui Yan

Legacy Theses & Dissertations (2009 - 2024)

The heterogeneous halogen chemistry plays a critical role in the ozone depletion events in the polar boundary layers. Pathways involving the conversion from photochemically active halogens to photochemically inactive halogens are necessary to understand the nature of ozone depletion, but the processes are not fully understood. The study of the effects of hydrogen peroxide (H2O2) and oxalic acid (C2H2


Homologous And Heterologous Crystallin Protein Interactions As The Molecular Basis Of Inherited Cataract, Priya Ranjan Banerjee Jan 2011

Homologous And Heterologous Crystallin Protein Interactions As The Molecular Basis Of Inherited Cataract, Priya Ranjan Banerjee

Legacy Theses & Dissertations (2009 - 2024)

Age-related cataract is the most common cause of blindness worldwide. Nearly fifty percent of Americans above the age of 75 are diagnosed with this disease (http://www.nei.nih.gov/eyedata/pbd_tables.asp), and surgical intervention is the sole method of treatment at present (http://www.nei.nih.gov/healthyvision/objective/cataracts.asp). In the developing world, even this treatment is not readily available. These are compelling reasons to search for better treatments to delay, prevent or arrest cataract formation. Recent evidence suggests that age-related cataracts also have a genetic component. Therefore, determining the mechanisms underlying genetic cataracts with a known association to a protein-mutation is one important strategy towards understanding the molecular basis for …


Band Structures Of Layered Carbon/Boron Nitride Materials With Commensurate Lattices, Christopher C. Wells Jan 2011

Band Structures Of Layered Carbon/Boron Nitride Materials With Commensurate Lattices, Christopher C. Wells

Legacy Theses & Dissertations (2009 - 2024)

The electronic structures of systems consisting of hexagonal boron nitride layers and graphite sheets have been investigated in detail using density functional theory methods with two exchange correlation functions (local density approximation and generalized gradient approximation). The experimental data of graphene, graphite, monolayer hexagonal BN, and hexagonal BN were reproduced well with computational models. The commensurate models used in the investigation were generated by taking the averages of the lattice constants for graphite and h-BN.


Biophysical Investigations Of The Molecular Basis Of Cataract Associated With The R76s Mutation In Human Gammad-Crystallin, Vurghun Ahmadov Jan 2011

Biophysical Investigations Of The Molecular Basis Of Cataract Associated With The R76s Mutation In Human Gammad-Crystallin, Vurghun Ahmadov

Legacy Theses & Dissertations (2009 - 2024)

Cataract disease results when the eye lens becomes opaque and scatters a significant part of the incoming light into the eye. The lens contains very high concentrations of the lens proteins, called crystallins, which are present at concentrations comparable to those found in protein crystals (about 400-600 mg/mL). Chemical modifications of the crystallins, such as oxidation and deamidation, or genetic mutations are known to result in increased light-scattering in vitro, and are implicated in cataract formation in vivo. Here we present the in vitro work on a mutant protein of human gammaD crystallin (HGD), namely R76S (i.e. Arg 76 to …


Heterometallic Beta-Diketonates And Oxo-Diketonates As Single Source Precursors For The Synthesis Of Oxide Materials, Haitao Zhang Jan 2010

Heterometallic Beta-Diketonates And Oxo-Diketonates As Single Source Precursors For The Synthesis Of Oxide Materials, Haitao Zhang

Legacy Theses & Dissertations (2009 - 2024)

The focus of this investigation was to develop a simple, high-yield synthetic approach to heterometallic diketonates using the same construction principles as for their polynuclear homometallic analogs. Several low-temperature solid-state synthetic routes were suggested that appear to be general for the preparation of heterometallic diketonates incorporating a wide range of s-, p-, d-, and f-metals. Using this investigative approach, two families of bimetallic homoleptic diketonates that contain heavy main group (BiIII, PbII) and the first row divalent transition metals (Mn, Fe, Co, Ni, Cu, and Zn) have been obtained. The heterometallic molecules that are held together by strong Lewis acid-base …


Elucidating The Structure Of Protein Aggregates By Raman Spectroscopy, Ludmila A. Popova Jan 2010

Elucidating The Structure Of Protein Aggregates By Raman Spectroscopy, Ludmila A. Popova

Legacy Theses & Dissertations (2009 - 2024)

The structures and properties of amyloid fibrils are of considerable interest due to their associations with numerous neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease and transmissible spongiform encephalopaties (prion diseases). Understanding fibrillogenesis at a molecular level requires detailed structural characterization of amyloid fibrils. However amyloid fibrils are difficult objects to study due to their non-crystalline and insoluble nature. These properties make the application of classical tools of structural biology, such as X-Ray crystallography and solution Nuclear Magnetic Resonance spectroscopy, impractical for structural characterization of protein fibrils.


Design And Development Of Highly Active, Nanoengineered, Platinum Based Core-Shell Electrodes For Proton Exchange Membrane Fuel Cells, Seth Louis Knupp Jan 2010

Design And Development Of Highly Active, Nanoengineered, Platinum Based Core-Shell Electrodes For Proton Exchange Membrane Fuel Cells, Seth Louis Knupp

Legacy Theses & Dissertations (2009 - 2024)

Highly active nanoengineered core-shell electrocatalyst have a great potential to be used as fuel cell electrodes. They can alleviate problems related with commercial carbon supported platinum by simultaneously lowering cost while enhancing reaction kinetics and overall performance. More recently, use of nanoengineered core-shell electrode structures have showed their ability to enhance the stability and overall lifetime of the catalyst without sacrificing the electrode's performance. We studied the potential of using highly active core-shell nanoparticles supported on carbon nanomaterials as fuel cell electrodes.


Arsenic Speciation Analysis Of Biological Fluids : A Study Of Liquid Chromatography Coupled To Analytical Atomic Spectrometric Instrumentation, Kanna Ito Jan 2010

Arsenic Speciation Analysis Of Biological Fluids : A Study Of Liquid Chromatography Coupled To Analytical Atomic Spectrometric Instrumentation, Kanna Ito

Legacy Theses & Dissertations (2009 - 2024)

Arsenic exists as many different chemical forms including inorganic, methylated and dietary species. The toxicity of these species varies: some are highly toxic and can cause adverse health effects in many parts of the body; others are considered relatively non-toxic. Monitoring arsenic exposure is usually accomplished by its direct measurement in biological fluids. Urine is the specimen of choice for assessing arsenic exposure, because of its short biological half-life in blood. There have been very few studies of arsenic species in blood, yet such research can provide valuable information on arsenic distribution and its metabolism in the body.