Chemistry Commons^™

Poly(Ester Amide) And Poly(Ethyl Glyoxylate) Nanoparticles For Controlled Drug Release, Amira Mohamed Moustafa

Electronic Thesis and Dissertation Repository

The objective of this research was to develop polymeric nanoparticles (NPs) having improved drug release properties for drug delivery. Poly(ester amide)s (PEAs) are promising biodegradable polymers. PEA NPs were prepared via emulsification-evaporation and salting-out methods and optimized through by varying different processing parameters. Polymer-model drug conjugates based on PEAs containing L-aspartic acid and rhodamine B were synthesized and used for NP preparation. Release behavior was studied and compared to a control system with physically encapsulated rhodamine B. It was shown that the release of rhodamine B from the covalent system did not show the burst effect and exhibited a slower …

Engineered Nanoparticles For Detection And Treatment Of Bacteria And Biofilms, Xiaoning Li

Doctoral Dissertations

Rapid and sensitive detection and identification of bacteria woud control and prevent bacterial infection and disease, enhancing the likelihood of early diagnosis and treatment. Especially developing effective biosensor for identification of bacteria species involved in formation of biofilms, which cause chronic and persistent diseases, would promote diagnostic and therapeutic efficiency. Conventional detection methods are limited by sensitivity and required time. First part of my research has been focused on developing a rapid, simple, and sensitive biosensor aiming at portable device application for detection of bacteria in water samples. This sensor is able to detect bacteria at low concentration and generate …

Modification Of Gold Nanoparticles For Sers Application In Emulsion And Lipid Systems, Michael J. Driver

Masters Theses

Gold nanoparticles produced using the Turkevich method were able to have their hydrophobicity modified using octanethiol in a novel method for SERS application. Both amphiliphic GNPs and hydrophobic GNPs were produced and differentiated by Raman signals. The amphiliphic GNPs were able to enhance the SERS signals of the protein emulsifier in the emulsion in situ and the hydrophobic GNPs were able to enhance the SERS signals from canola oil. Further purification of the hydrophobic GNPs proved to have higher enhancement and sensitivity, but still poor consistency which is typical of SERS. Monitoring lipid oxidation using Raman and SERS using alternative …

Photochromic Molecular Materials For The Controlled Organization Of Nanoparticles, Kristen Elise Snell

Electronic Thesis and Dissertation Repository

The displacement of polystyrene nanoparticles promoted by bulk azo mass transfer using interferential light illumination will be discussed. For this a variety of different push pull small azo molecules were synthesis and characterized, changing the polarity, hydrophobicity and bulky groups around the azo moiety. These small dyes appear to orientate quicker than similarly report azo polymers, of entanglement of the azobenzene group in the polymeric backbone. These dyes were used to form surface relief grating on the thin films due to the bulk mass transfer. This mass transfer was exploited to align polystyrene nanoparticles in the crests and troughs of …

Mass Spectrometric Characterization And Imaging Of Nanoparticles In Biological Samples, Bo Yan

Doctoral Dissertations

Nanoparticles (NPs) are being investigated widely for use in biomedical applications such as imaging, drug delivery, and cancer therapy due to their small size and readily tunable properties. The ability to accurately characterize NPs and monitor their spatial distributions is highly desirable for effective use of NPs and evaluation of their potential adverse environmental, health, and safety effects. In this dissertation, a simple, fast, and sensitive method based on laser desorption/ionization mass spectrometry (LDI-MS) to characterize and track NPs in biological systems has been developed. This method is especially well suited for characterizing core-shell structured NPs, such as quantum dots …

Synthesis And Characterization Of Polymer Nanomaterials Using Controlled Radical Polymerization, Lei Wang

Theses and Dissertations

This research focuses on creating and investigating polymer/organic bound interfaces on nanoparticles with advanced architectures to tailor the properties of polymer nanocomposites for various applications. Reversible addition-fragmentation chain transfer (RAFT) polymerization and a toolbox of surface functionalization from the simple to the advanced were developed to prepare the polymer nanomaterials.

In the first part (Chapter 2), a variety of RAFT agents (xanthate, dithiocarbamate and trithiocarbonate) were used to mediate the polymerizations of several classes of free radical polymerizable monomers. These monomers consist of styrene, methyl acrylate, methyl methacrylate, vinyl acetate and isoprene, which have different activities and require different classes …

Determination Of Thiamine In Solution By Uv-Visible Spectrophotometry: The Effect Of Interactions With Gold Nanoparticles, Michael Vincent Zielinski

Master's Theses and Doctoral Dissertations

The method presented here provides the foundation for a simple and selective qualitative determination of thiamine in solution. Gold nanoparticles in the presence of thiamine results in the formation of a secondary peak in the absorbance spectrum of the mixture. This peak can be used as an indicator of thiamine, which is useful for the qualitative analysis of solutions, and may provide an alternative to other methods for evaluating thiamine in blood and other biological systems. This method uses gold nanoparticles of a size around 20 to 30 nm and involves their selective interaction with thiamine, compared to selected amino …

Synthesis And Characterization Of Cobalt Carbide Based Nanomaterials, Zachary Huba

Theses and Dissertations

Permanent magnets are used heavily for multiple applications in industry and current electronic technologies. However, the current permanent landscape is muddled by high cost of materials and insufficient magnetic or thermal properties. The primary focus of this dissertation work is the synthesis and optimization of a new permanent magnetic material, in the form of cobalt carbide nanomaterials. The optimization revolved around controlling the crystal phase and particle shape of synthesized cobalt carbide particles; these parameters have significant impact on the observed magnetic properties of magnetic nanoparticles. Co₃C was identified to be the preferred crystal phase, leading to better …

Surface Functionalization And Bioconjugation Of Nanoparticles For Biomedical Applications, Longyan Chen

Electronic Thesis and Dissertation Repository

Colloidal inorganic nanoparticles (NPs) have been attracting considerable interest in biomedicine, from drug and gene delivery to imaging, sensing and diagnostics. It is essential to modify the surface of nanoparticles to have enhanced biocompatibility and functionality for the in vitro and in vivo applications, especially in delivering locally and recognizing biomolecules. Herein, the goal of this research work is to develop advanced NPs with well-tailored surface functionalities and/or bio-functionality for the applications in cell tracking and analytes detection.

In the first project, quantum dots incorporating with gelatin nanoparticles (QDs-GNPs) have been developed for bioimaging applications. Two different approaches have been …

Determination Of The Uptake And Effects Of Tio2 Nanoparticles In Cucumber (Cucumis Sativus), Alia D. Servin

Open Access Theses & Dissertations

The profuse use of nanoparticles (NPs) in consumer products has raised concerns about their impacts in environmental and human health and possible transfer into the food chain through plants. Cucumber (Cucumis sativus L.) is a widely cultivated garden vegetable that could be in contact with NPs through biosolids. In this Dissertation research, the impact of TiO2 NPs was evaluated in cucumber plants grown in hydroponics and sandy loam soil. Hydroponically grown plants were treated for 15 days with 0-4000 mg/L of TiO2 NPs, and their vegetative tissues were studied using synchrotron micro X-Ray Fluorescence (micro-XRF) and Micro X-ray Absorption Near …

Impact Of Zinc Oxide Nanoparticles On Green Pea Plant & Seed Quality And Effects On Physiological Traits Of Green Peas, Corn, And Zucchini By Silver Nanoparticles, Arnab Mukherjee

Open Access Theses & Dissertations

The production and use of numerous engineered nanomaterials (ENMs) have increased exponentially over the past decade. Nanoparticles (NPs), ENMs possessing diameter between 1-100 nm, (NPs), are widely used in many applications. Worldwide consumption of NPs has increased their possible release into the environment. This, in turn, has elevated the extent of the potential impacts of NP exposure to living and non-living organisms. This is why the assessment of the impact of NPs on different environmental components, especially on plants, the producer in the food web, has become a very important aspect of nano-ecotoxicology. However, studies focusing on phytotoxicity and effects …

Gold-Magnetite Nanoparticle-Biomolecule Conjugates: Synthesis, Properties And Toxicity Studies, Akshay Pariti

Masters Theses

"This thesis study focuses on synthesizing and characterizing gold-magnetite optically active magnetic nanoparticle and its conjugation with biomolecules for biomedical applications, especially magnetic fluid hyperthermia treatment for cancerous tissue. Gold nanoparticles have already displayed their potential in the biomedical field. They exhibit excellent optical properties and possess strong surface chemistry which renders them suitable for various biomolecule attachments. Studies have showed gold nanoparticles to be a perfect biocompatible vector. However, clinical trials for gold mediated drug delivery and treatment studied in rat models identified some problems. Of these problems, the low retention time in bloodstream and inability to maneuver externally …

Scanning Probe Investigations Of Magnetic Nanoparticles, Protein Binding And The Synthesis Of Rare Earth Oxide Nanoparticles Using Nanoscale Lithography, Lauren Elizabeth Englade-Franklin

LSU Doctoral Dissertations

Approaches to prepare spatially selective surfaces were developed in this dissertation for constructing assemblies of biomolecules and inorganic materials. Nanoscale surface patterns of organic thin films were prepared using particle lithography combined with organosilane chemistry. Biological and inorganic nanomaterials can be patterned with tailorable periodicities, which can be controlled by selecting the diameter of mesospheres used as surface masks. The surface platforms of well-defined nanopatterns are ideal for high resolution investigations using scanning probe microscopy (SPM). Local measurements of surface properties combined with visualization of the steps of chemical reactions at the molecular level were accomplished. Fundamental studies of the …

Synthetic Routes To Therapeutic Agents Via Masked Functionalities: From Orthogonal Peptide Crosslink To Photothermal Cancer Prodrug, Chyree Shantel Batton

LSU Doctoral Dissertations

The theonellamides are a family of compounds distinguished by their crosslinking ô-histidinoalanine (ô-HAL) residue. Part one of this dissertation details the synthesis of an orthogonally protected ô-HAL building block that will be incorporated into a total synthesis of theonellamide C. Selective deprotection of each amine and acid of this orthogonally protected building block is also demonstrated. Various reaction partners for the assembly of ô-histidinoalanine were explored. One approach involved the coupling of N-Fmoc-â-iodoalanine benzyl ester and (Nðim)-blocked histidine nucleophiles including a fused bicyclic urea and a Boc-His(Nð-Pac)-OMe. While the imidazolium salts were identified by mass spectrometry, elimination of the iodide …