Other Chemistry Commons^™

Mapping Gadolinium Contrast In A Complex Ionic And Photosynthesis Environment Of Pineapple By Near-Infrared And X-Ray Imaging, Subhendra Sarkar, Zoya Vinokur, Chen Xu, Tetiana Soloviova, Amina Shahbaz, Aldona Gjoni

Publications and Research

This work explores the diffusivity of a lanthanide complex, Eovist (Gadolinium-Ethoxy Benzyl Diethylenetriamine pentaacetate) that is stable in neutral media but is not in acidic environment. In the current work an acidic fruit model like pineapple that is rich in transition metals was used and a possible transmetallation reaction among Eovist and transition metal complexes was tested using X-ray imaging. Another goal of this work was to perturb the usual and the unusual photosynthesis systems that pineapple has maintained for millions of years during the evolution of circadian genes for efficient water conservation by dark photosynthesis. To detect such photosynthesis …

Allosteric Regulation At The Crossroads Of New Technologies: Multiscale Modeling, Networks, And Machine Learning, Gennady M. Verkhivker, Steve Agajanian, Guang Hu, Peng Tao

Mathematics, Physics, and Computer Science Faculty Articles and Research

Allosteric regulation is a common mechanism employed by complex biomolecular systems for regulation of activity and adaptability in the cellular environment, serving as an effective molecular tool for cellular communication. As an intrinsic but elusive property, allostery is a ubiquitous phenomenon where binding or disturbing of a distal site in a protein can functionally control its activity and is considered as the “second secret of life.” The fundamental biological importance and complexity of these processes require a multi-faceted platform of synergistically integrated approaches for prediction and characterization of allosteric functional states, atomistic reconstruction of allosteric regulatory mechanisms and discovery of …

Analytic Gradients For State-Averaged Multiconfiguration Pair-Density Functional Theory, Thais R. Scott, Matthew R. Hermes, Andrew M. Sand, Meagan S. Oakley, Donald G. Truhlar, Laura Gagliardi

Scholarship and Professional Work - LAS

Analytic gradients are important for efficient calculations of stationary points on potential energy surfaces, for interpreting spectroscopic observations, and for efficient direct dynamics simulations. For excited electronic states, as are involved in UV–Vis spectroscopy and photochemistry, analytic gradients are readily available and often affordable for calculations using a state-averaged complete active space self-consistent-field (SA-CASSCF) wave function. However, in most cases, a post-SA-CASSCF step is necessary for quantitative accuracy, and such calculations are often too expensive if carried out by perturbation theory or configuration interaction. In this work, we present the analytic gradients for multiconfiguration pair-density functional theory based on SA-CASSCF …

The Development Of A Surface Enhanced Raman Spectroscopy Method For The Detection Of Synthetic Cannabinoids In Urine, Thaddeus Mostowtt

FIU Electronic Theses and Dissertations

The use and abuse of synthetic cannabinoids has increased significantly in recent years due to their easy access and growing popularity. Despite having more known drugs become illegal, new synthetic versions of these drugs are being made that have not yet been recognized or classified as illegal substances. Therefore, standard methods may not be able to detect these drugs.

The most common method of screening detection for drugs of abuse in biological samples is the immunoassay. However, the immunoassay method presents some disadvantages, particularly for newly synthesized compounds. More advanced methods have also been used, such as LC-MS; however, these …

The Recreation Of Wound Patterns Using Various Tissue Simulants For Crime Scene Reconstruction, Breanne Steimle

Forensic Science Master's Projects

Within the field of forensic science, there are limited reliable methods for the simulation of pattern injuries on human skin and tissue that may aid in aspects of crime scene reconstruction. The tissue simulant must be of sufficient integrity for recording blunt force trauma and bite mark impressions, electrocution, cutting, and gunshot wound related injuries for the purpose of re-enactment, court exhibition, and distance determination. For wound reenactments (such as blunt force trauma, bite mark impressions and electrocution), dead skin and tissue from human cadavers do not show wounding patterns that would occur on live tissue. This study examines different …

Leaf Traits Can Be Used To Predict Rates Of Litter Decomposition, Marc Rosenfield, Jennifer L. Funk, Jason K. Keller, Catrina Clausen, Kimberlee Cyphers

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Strong relationships exist between litter chemistry traits and rates of litter decomposition. However, leaf traits are more commonly found in online trait databases than litter traits and fewer studies have examined how well leaf traits predict litter decomposition rates. Furthermore, while bulk leaf nitrogen (N) content is known to regulate litter decomposition, few studies have explored the importance of N biochemistry fractions, such as protein and amino acid concentration. Here, we decomposed green leaves and naturally senesced leaf litter of nine species representing a wide range of leaf functional traits. We evaluated the ability of traits associated with leaf and …

Systematic Comparison Of Pre-Treatment Parameters In Forensic Hair Analysis And Investigating Hair-Drug Interactions, Jennett Chenevert Aijala

FIU Electronic Theses and Dissertations

Forensic toxicological analysis for the purposes of protecting human health and supporting criminal justice activities can be achieved, in part, by means of analysis of human head hair for detection of abused substances. Hair is considered an alternative sample matrix (compared to blood and urine) because of persistent interpretive challenges caused by a lack of standardization in analytical approaches and poor understanding of the biases resulting from physicochemical interactions between major hair components (e.g., melanin) and drugs of abuse. Some of the uncertainty regarding optimal techniques for the pre-treatment of hair specimens results from the unknown nature of the …

I. Non-Degradable Polysiloxane Networks For Controlled Release Applications, And Ii. Additive Free, Degradable Silyl-Ether Furyl-Maleimide Networks, Caleb M. Bunton

Chemistry Theses and Dissertations

I. Two different series of non–degradable polysiloxane networks were prepared for the encapsulation and controlled release of a small molecule agent. For the first series, hydrosilylation was utilized to prepare networks of varying crosslink densities, as determined from swelling studies, from vinyl terminated and silylhydride functional poly(dimethyl)siloxanes. For the second series, the thiol-ene reaction was utilized to prepare networks of varying crosslink densities, as determined from swelling studies, from vinyl terminated and mercaptopropyl functional poly(dimethyl)siloxanes. Nile red dye was used as an encapsulated agent and dye release from each series of networks was measured using UV–vis spectroscopy to determine controllability …

Chemistry In Art: The Science Of Dye, Madeleine Gray Burland

Honors Projects

Fabric arts, and the practice of dyeing fabric using various resist techniques, is a tradition that goes back centuries, and is unique among art mediums in its relation to science, as the innovations in dye production have directly affected the art form. The development of synthetic dyes in the 1800’s greatly affected the way fabric is dyed, and subsequently the way clothes were made and consumed. As opposed to dyes made of natural materials, synthetic dyes cam in more colors, were brighter, easier to make in large quantities, and lasted longer since they didn’t fade with repeated washings. The practice …

Isolation, Identification, And Investigation Of A Novel Bioactive Furanocoumarin From Leaves Of Amyris Elemifera, Amy K. Bracken

Honors Theses

Plants produce biologically active compounds that humans have utilized for many agricultural applications. Amyris elemifera was investigated due to the known bioactivity of its family, Rutaceae, and its use in medicines in tribes of the Bahamas. Biotage® and TLC guided fractionation of the EtOAc, hexane, and MeOH extracts of the leaves of Amyris elemifera yielded bioactive compounds. Most significantly, a novel furanocoumarin, 8-(3-methylbut-2-enyloxy)-marmesin acetate (1), and its analog 8-(3-methylbut-2-enyloxy)-marmesin (2), were isolated. The structures were identified via NMR and X-ray crystallography techniques; the X-ray crystal structure for 1 was reported for the first time, and the …

Mechanistic Study Of Cooperative Ligand-Centered Reactivity In Triaminoborane-Bridged Diphosphine Complexes, Clara Kirkvold

Honors Thesis

Reactive ligand platforms containing trisubstituted boranes have been effective in promoting new types of small molecule reactivity and catalysis with transition metals. Our project is aimed at developing triaminoborane-bridged diphosphines that participate in cooperative ligand-centered reactivity while bound to transitions metals. Here we present a density functional theory (DFT) mechanistic study on a series of ligand centered reactions at a boron center on a metal complex, ^PhTBDPhosMCl₂ (M = Ni or Pd and TBDPhos = 1,8,10,9-triazaboradecalin). Our work focuses specifically on the nickel complexes. ^PhTBDPhosNiCl₂ can react with several molecules to produce trans H-X addition (X=OH …

Resolution Of Portable Raman Spectrometers And Its Effect On The Analysis Of Biological Specimens, Jalissa Thomas

Chemistry

Body fluid traces are a common and a major form of evidence that can be found at a crime scene, as it is a good source of DNA. As such, it is vital that body fluid evidence is properly detected and identified. Issues with the current methods of identifying body fluids and the large backlog of evidence in most forensic labs call for more accurate on-scene (in situ) body fluid identification. Past research has demonstrated that Raman spectroscopy is an advantageous tool for accurately and quickly identifying body fluids, namely in the laboratory. Portable Raman instruments have been …

Effect Of Charged Lipids On The Ionization Behavior Of Glutamic Acid Containing Transmembrane Helices, Brooke Nunn

Chemistry & Biochemistry Undergraduate Honors Theses

Transmembrane proteins make up critical components of living cells. Protein function can be greatly impacted by the charged state of its respective components, the side chains of amino acid residues. Thus far, in the lipid membrane, little is known about the properties of residues such as glutamic acid. To explore these properties, I have included glutamic acid in a suitable model peptide-lipid system for fundamental biophysical experiments. Within the system, I have placed a glutamic acid residue instead of leucine in the L14 position of the helical hydrophobic peptide GWALP23 (acetyl-GGALWLALALALAL¹⁴ALALWLAGA-amide). Substitutions of glutamine and aspartic acid serve …

The Ability Of Vitreous Metabolite Concentration To Determine Time Of Death, Victoria Wiggins

Themis: Research Journal of Justice Studies and Forensic Science

This paper analyzes the ability of vitreous fluid to determine time of death. The high variability in current methods used to establish post-mortem interval (PMI), or the amount of time between death and post-mortem examination make it difficult to obtain an accurate estimation. The concentration of metabolites found within vitreous fluid, such as potassium (K+), hypoxanthine (Hx), and magnesium (Mg), are the most researched alternatives to traditional methods in PMI determination because of the relative isolation of vitreous within the body and its ability to withstand degradation. There is no clear consensus on which metabolite provides the most accurate data …

295— Biomimicry: Investigating The Active Site Model Of Lactate Racemase, Stephanie Podguski, Maisy Ross

GREAT Day Posters

Because of humans’ heavy impact on nature with industrialization and resource extraction, biomimetics, also known as biomimicry, is a study that has emerged. Biomimetics utilizes observations from nature to comprehend the principles of underlying mechanisms and apply concepts that may benefit science, medicine, engineering and the like. An area of biochemistry we are applying this to is the lactate racemase enzyme.This metalloenzyme is found in many prokaryotic organisms and catalyzes the interconversion between the two optical isomers of lactic acid. The structure of this enzyme consists of a square-planar nickel (II) ion coordinated by a histidine residue and a pincer …

Biological Evaluation Of Fda-Approved Drugs As Mirna-31 Inhibitors Using Real Time Qrt-Pcr And A Luciferase Assay, Nicholas Sienkiewicz

Honors Theses

MicroRNAs (miRNAs) are a group of post-transcriptional, negative regulators of gene expression, consisting of ~19-24 nucleotides. Since their discovery in 1993, miRNAs have been found to be involved in a diverse amount of cellular and disease pathways, including certain types of cancer. Overexpression of certain oncogenic miRNAs, including miRNA-31, have been shown to play a role in cancer cell development. Recent findings have suggested that miRNAs play a significant role in every stage of colorectal cancer (CRC) initiation, progression, and development, as well as induce resistance to chemotherapy drugs like 5-FU. In particular, research has shown that increased levels of …

Quantification Of Vitamin B12 In Two Cricket Species, Haley Smeltz

Student Scholar Showcase

Entomophagy, or the eating of insects, has been practiced in the eastern world for centuries, however it is currently overlooked in the western nations. Studies have shown that insects, such as crickets, contain high levels of protein and minerals, however vitamin content is rarely studied. This study aims to quantify the vitamin B₁₂ content in two cricket species, the common house cricket (Acheta domesticus) and the banded cricket (Gryllodes sigillatus). The vitamin B₁₂ content of both cricket species will be quantified using reverse-phase high performance liquid chromatography (RP-HPLC). Prior to RP-HPLC analysis, all the …

Chemistry 104 Laboratory Manual, Boris Kalmatsky

Open Educational Resources

No abstract provided.

Using Surface-Enhanced Raman Scattering Of Gold Nanostars For Encoding Molecular Information, Samantha E. Curry

Honors Thesis

Increases in the selling of illicit goods warrant a subsequent need for even more sophisticated methods to prevent counterfeit products from being sold. Surface-enhanced Raman spectroscopy (SERS) has the potential to be a powerful tool to thwart counterfeiters because the unique security tags fabricated with this method are difficult to reproduce without knowing the “secret” recipes used in their preparation. In this work, gold nanostars are used as SERS active substrates since their branched structure allows for strong coupling between the light and plasmonic nanoparticles. As a result, Raman signals of trace amount of chemicals can be easily detected. The …

Quantum Chemical Lipophilicities Of Antimalarial Drugs In Relation To Terminal Half-Life, Joseph D. Alia, Sheila Karl, Tyler D. Kelly

Chemistry Publications

According to the WHO, artemisinin-based combination therapies (ACTs) have been integral to the recent reduction in deaths due to Plasmodium falciparum malaria. ACT-resistant strains are an emerging problem and have evolved altered developmental stages, reducing exposure of the most susceptible stages to artemisinin drugs in popular ACTs. Lipophilicity, log K_ow, is a guide in understanding and predicting pharmacokinetic properties such as terminal half-life which alters drug exposure. Consistent log K_ow values are not necessarily available for artemisinin derivatives designed to extend terminal half-life, increase bioavailability, and reduce neurotoxicity. For other drugs used in ACTs, an assortment of …