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Full-Text Articles in Physical Sciences and Mathematics

Preparation Of Folic Acid-Carbon Dots-Doxorubicin Nanoparticles As Targeting Tumor Theranostics, Samson Dada Dec 2019

Preparation Of Folic Acid-Carbon Dots-Doxorubicin Nanoparticles As Targeting Tumor Theranostics, Samson Dada

Electronic Theses and Dissertations

Carbon dots (CDs) have attracted much attention as an excellent gene/drug delivery and biological imaging agent for early cancer theranostics. In this study, we prepared two series of nanoparticles (NPs), which are composed of (CDs) with a targeting agent, folic acid (FA), and a chemotherapeutic agent Doxorubicin (Dox). All the NPs and their intermediates were characterized using ultraviolet-visible spectroscopy (UV-vis), fluorescence spectroscopy, and Fourier transform-infrared spectroscopy (FT-IR). The drug loading capacity (DLC) and drug loading efficiency (DLE) of two series of FA-CDs-Dox were assessed using UV-vis absorption spectroscopy at the wavelength of 485 nm. Both showed good DLE and DLC …


Electrochemical Determination Of Surface Area-To-Volume Ratio For Metal Nanoparticle Analysis., Jay Narayan Sharma Dec 2019

Electrochemical Determination Of Surface Area-To-Volume Ratio For Metal Nanoparticle Analysis., Jay Narayan Sharma

Electronic Theses and Dissertations

This dissertation describes an electrochemical approach for measuring the surface area-to-volume ratio (SA/V) of electrode-attached metal nanoparticles (NPs), which was used to analyze their size, aggregation state, and porosity. This dissertation further describes the effect of the metal NP electrode assembly method on the SA/V, which is related to metal NP catalytic activity and stability. Cyclic voltammetry (CV) in acid electrolyte followed by anodic stripping voltammetry (ASV) in KBr electrolyte allows the electrochemical measurement of the SA/V of electrode-attached Au nanospheres (NSs). In CV, the forward scan produces a thin surface Au2O3 layer on the Au NSs. …


Electrification Ionization: Fundamentals And Applications, Bijay Kumar Banstola Nov 2019

Electrification Ionization: Fundamentals And Applications, Bijay Kumar Banstola

LSU Doctoral Dissertations

Electrification ionization is a method to produce ions from solid samples by charge separation. This separation of charge can be enhanced by organic molecules known as matrix compounds to produce highly charged molecules. In this research, new methods were developed for the application of electrification ionization for surface analysis and the ionization mechanism was investigated. First, an electrification ionization matrix was used for tissue imaging using laser ablation. A two-component matrix of 2-nitrophloroglucinol and silica nanoparticles was found to increase the number of multiply charged ions from the tissue. Images of mouse brain with multiply charged ions were obtained. In …


Zinc–Phosphorus Clusters For Solution Synthesis Of Zinc Phosphide Nanoparticles, Kyungseop Lee Oct 2019

Zinc–Phosphorus Clusters For Solution Synthesis Of Zinc Phosphide Nanoparticles, Kyungseop Lee

Electronic Thesis and Dissertation Repository

Synthesis of zinc phosphide (Zn3P2) nanoparticles is an emerging topic of investigation as Zn3P2 is a candidate material for the next generation solar cells. Despite the early discovery of its favorable electronic properties that are well-suited for photovoltaic applications, a major focus of synthetic strategy was with vapor/chemical deposition methods. Solution methods with greater control over size, crystal structure and composition at a lower production cost, has been underdeveloped in comparison. In this context, this thesis describes the synthesis, characterization and reactivity of zinc phosphido clusters: [Zn2(μ-PPh2)2(PPh …


Visible And Ultraviolet Upconversion And Near Infrared Downconversion Luminescence From Lanthanide Doped La2zr2o7 Nanoparticles, Santosh K. Gupta, Mitzy A. Penilla Garcia, Jose P. Zuniga, Maya Abdou, Yuanbing Mao Oct 2019

Visible And Ultraviolet Upconversion And Near Infrared Downconversion Luminescence From Lanthanide Doped La2zr2o7 Nanoparticles, Santosh K. Gupta, Mitzy A. Penilla Garcia, Jose P. Zuniga, Maya Abdou, Yuanbing Mao

Chemistry Faculty Publications and Presentations

Single materials which have a multitude of photophysical processes by selective doping are in high demand in the community of material science due to their multifunctional applications. Upconversion (UC) and downconversion (DC) luminescence properties of lanthanide doped nanoparticles (NPs) are imperative for their broad application potentials. Here, we describe two series of either doubly or triply doped La2Zr2O7 NPs synthesized by a molten salt method. For the former, La2Zr2O7:Yb,Er NPs display bright red and moderate green UC (VUC) and NIR-B DC (NDC) at around 1550 nm, which are highly desirable for in-vivo bioimaging applications. For the latter, La2Zr2O7:Gd,Yb,Tm NPs demonstrate …


The Development Of Multi-Functional System That Combine Patterned Hydrogels, Plasmin-Degradable Nanoparticles And Stem Cells For Applications In Tissue Engineering And Growth Factors Delivery, Safaa I. Kader Oct 2019

The Development Of Multi-Functional System That Combine Patterned Hydrogels, Plasmin-Degradable Nanoparticles And Stem Cells For Applications In Tissue Engineering And Growth Factors Delivery, Safaa I. Kader

Theses and Dissertations

This thesis spots the light on the development of a novel multi-functionalized system for application in tissue engineering and on-demand morphogens delivery. Three types of materials used in this study are synthetic polymer, biopolymer, and nanomaterials. Polyethylene glycol (PEG), a synthetic polymer was chosen in this study because of its high biocompatibility, non-immunogenicity, inert nature, ease of modification, and reduces protein denaturation to provide a wide range of physical and mechanical properties. Here, PEG is used one time as a hydrogel, linear polyethylene glycol-co-lactide (LPELA), and another time as peptide-PEG based nanoparticles (PxSPCP). Gelatin, a natural polymer has been widely …


Synthesis And Characterization Of Multifunctional Transition Metal Oxide Nanoparticles Through A Modified Sol-Gel Method With Application In Energy Storage, Julien Lombardi Sep 2019

Synthesis And Characterization Of Multifunctional Transition Metal Oxide Nanoparticles Through A Modified Sol-Gel Method With Application In Energy Storage, Julien Lombardi

Dissertations, Theses, and Capstone Projects

The Synthesis of transition metal oxide nanoparticles has been studied in great detail over the many years. The most studied transition metal oxide nanoparticles are perovskites of the ABO3 stoichiometry (A and B = transition metal) and more recently double perovskite crystal structures of the AA’BO6 or A2BB’O6 stoichiometry due to the many different properties arising from the many different combinations of elements possible. These materials have proven potentially useful in many fields, but due to properties such as ferroelectricity and ferromagnetism, the desire to integrate these materials into electronics is ever growing. Many synthesis …


Bordering Conditions Determination For Nanocomposites Special Properties, Tokhir Rakhimov, Muhtor Mukhamediev, Dilfuza Gafurova Aug 2019

Bordering Conditions Determination For Nanocomposites Special Properties, Tokhir Rakhimov, Muhtor Mukhamediev, Dilfuza Gafurova

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

The paper is devoted to determination of active nanoparticles sizes. Other particles bigger or smaller of calculated size limits are not demonstrated the special activity, on the example of catalytic elimination of environmental pollutants, namely, carbon monoxide, under ambient conditions - low temperature, high humidity, the presence of anthropotoxins. Discusses basic understanding of catalysts used in environmental pollution abatement, in particular, high activity of nanocatalysts with certain sizes and lack of activity of catalysts particles with other sizes. Nevertheless it remains unclear why massive objects containing palladium, as well as true solutions are not effective as catalysts for low-temperature carbon …


Erratum: "Imaging The Three‐Dimensional Orientation And Rotational Mobility Of Fluorescent Emitters Using The Tri‐Spot Point Spread Function", Oumeng Zhang, Jin Lu, Tianben Ding, Matthew D. Lew Aug 2019

Erratum: "Imaging The Three‐Dimensional Orientation And Rotational Mobility Of Fluorescent Emitters Using The Tri‐Spot Point Spread Function", Oumeng Zhang, Jin Lu, Tianben Ding, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

In the original paper, a calibration error exists in the image-formation model used to analyze experimental images taken by our microscope, causing a bias in the orientation measurements in Figs. 2 and 3. The updated measurements are shown in Fig. E1. We have also updated the supplementary material for the original article to discuss the revised PSF model and estimation algorithms (supplementary material 2) and show the revised model and measurements (Figs. S1, S3, S7, S8, and S10–S13).


Synthesis And Characterization Of Gd-Doped Inp/Zns Quantum Dots For Use In Multimodal Imaging Probes, Molly Erin Duszynski Aug 2019

Synthesis And Characterization Of Gd-Doped Inp/Zns Quantum Dots For Use In Multimodal Imaging Probes, Molly Erin Duszynski

MSU Graduate Theses

Quantum dots (QDs), which are intensely fluorescent nanocrystals ranging 2-10 nanometers in diameter, have shown promise in fluorescence imaging. However, in vivo applications of QDs are limited due to the opaque surrounding of tissue and bones. In this study, InP/ZnS QDs were doped with a paramagnetic atom in an attempt to render them MRI-active. We have further bioconjugated these nanoprobes to develop highly specific MRI-active probes that can be used for detection of neurodegenerative diseases. These bioconjugated nanoprobes detect a mutated form of alpha-synuclein that forms oligomers that are a hallmark of Parkinson’s disease andother alpha-synucleinopathies. Here, we have optimized …


Designed Guanidinium-Rich Amphipathic Oligocarbonate Molecular Transporters Complex, Deliver And Release Sirna In Cells, E. I. Geihe, Christina B. Cooley, J. R. Simon, M. K. Kiesewetter, J. A. Edward, R. P. Hickerson, R. L. Kaspar, J. L. Hedrick, R. M. Waymouth, P. A. Wender Jun 2019

Designed Guanidinium-Rich Amphipathic Oligocarbonate Molecular Transporters Complex, Deliver And Release Sirna In Cells, E. I. Geihe, Christina B. Cooley, J. R. Simon, M. K. Kiesewetter, J. A. Edward, R. P. Hickerson, R. L. Kaspar, J. L. Hedrick, R. M. Waymouth, P. A. Wender

Christina B Cooley

The polyanionic nature of oligonucleotides and their enzymatic degradation present challenges for the use of siRNA in research and therapy; among the most notable of these is clinically relevant delivery into cells. To address this problem, we designed and synthesized the first members of a new class of guanidinium-rich amphipathic oligocarbonates that noncovalently complex, deliver, and release siRNA in cells, resulting in robust knockdown of target protein synthesis in vitro as determined using a dual-reporter system. The organocatalytic oligomerization used to synthesize these co-oligomers is step-economical and broadly tunable, affording an exceptionally quick strategy to explore chemical space for optimal …


Synthesis, Stabilization, And Modification Of Zinc Oxide Nanoparticles For Biological Applications, Allison Kimberly Freese May 2019

Synthesis, Stabilization, And Modification Of Zinc Oxide Nanoparticles For Biological Applications, Allison Kimberly Freese

MSU Graduate Theses

Nanoparticles have become very useful as delivery systems in biomedicine. The nanoparticles can be layered with different compounds to produce a vessel for transport of biological materials. Specifically, gold nanoparticles layered with a reducing agent, lysozyme, and polyelectrolytes can be synthesized to transport lysozyme into a cell. However, zinc oxide nanoparticles are cheaper, biocompatible nanoparticles that can be used for the same process. Here in, zinc oxide nanoparticle conjugates were synthesized, modified, and analyzed to be used as a biological material delivery system. The zinc oxide nanoparticles were synthesized using zinc chloride and sodium hydroxide. The particles were then layered …


Molten-Salt Synthesized Pyrochlore Nanoparticles For Multifunctional Applications, Jose P. Zuniga May 2019

Molten-Salt Synthesized Pyrochlore Nanoparticles For Multifunctional Applications, Jose P. Zuniga

Theses and Dissertations

There is a need in the scientific world to design and develop high quality nanomaterials with multifunctional applications. In this work, we explore the molten-salt method (MSS) as a new green method for the synthesis of complex metal oxides. We adjusted all synthesis parameters such as time, temperature and pH to generate an optimum La2Hf2O7 nanoparticle with a well define shape and surface. Activator ions such as Eu3+, Tb3+, Dy3+, Bi3+ and uranium ion (U4+, U6+) were used to monitor its structural and optical behavior effect when doped.

Our results showed effective quantum yield, thermal, pressure stability, near to white …


Deposition Of Platinum Particles On Surface-Modified Carbon Ultramicroelectrodes, Caitlin Millsaps May 2019

Deposition Of Platinum Particles On Surface-Modified Carbon Ultramicroelectrodes, Caitlin Millsaps

Undergraduate Honors Theses

Nanoparticles are used as electrocatalysts due to their large surface area-to-volume ratios. Most studies of nanoparticle electrocatalysis are performed on collections of particles on a support, which represent ensemble average behavior influenced by spatial distribution of the nanoparticles. Therefore, recent emphasis has been placed on analyzing electrocatalytic behavior of single particles. The focus here is to develop carbon ultramicro- and nanoelectrode platforms for studying the electrocatalytic properties of single metal nanoparticles. Ultramicroelectrodes were prepared using chemical vapor deposition of carbon in pulled quartz capillaries. Electrode diameters were determined by cyclic voltammetry. Electrodes were modified using a soft nitriding technique to …


Roles Of Oxygen Vacancies And Ph Induced Size Changes On Photo- And Radioluminescence Of Undoped And Eu3+-Doped La2zr2o7 Nanoparticles, Santosh K. Gupta, Maya Abdou, Jose P. Zuniga, Partha Sarathi Ghosh, Enrique Molina, Ben Xu, Mircea Chipara, Yuanbing Mao May 2019

Roles Of Oxygen Vacancies And Ph Induced Size Changes On Photo- And Radioluminescence Of Undoped And Eu3+-Doped La2zr2o7 Nanoparticles, Santosh K. Gupta, Maya Abdou, Jose P. Zuniga, Partha Sarathi Ghosh, Enrique Molina, Ben Xu, Mircea Chipara, Yuanbing Mao

Chemistry Faculty Publications and Presentations

Defect, doping and particle size play important roles on the optical performance of nanophosphors. In this study, undoped La2Zr2O7 NPs (LZO) displayed multicolor emission under UV irradiation due to the presence of ionized oxygen vacancies in the band gap. In addition, we explored the effect of particle size of La2Zr2O7:Eu3+ (LZOE) NPs on their structure, surface area, photoluminescence, radioluminescence, lifetime and quantum yield. There is progressive decrease in luminescence output and quantum yield as the coprecipitation pH is raised to prepare the single-source precursors for the molten salt synthesis of the NPs. Under X-ray irradiation, the LZOE …


Use Of Anodic Stripping Voltammetry To Study The Size-Selective Electrophoretic Deposition And Aggregation-Dependent Oxidation Of Metal Nanoparticles., Stacy L. Allen May 2019

Use Of Anodic Stripping Voltammetry To Study The Size-Selective Electrophoretic Deposition And Aggregation-Dependent Oxidation Of Metal Nanoparticles., Stacy L. Allen

Electronic Theses and Dissertations

This dissertation describes how anodic stripping voltammetry (ASV) was used to study size-controlled electrophoretic deposition (EPD) and the aggregation-dependent oxidation properties of citrate-stabilized Au nanoparticles (NPs). EPD of citrate-coated Au NPs occurs in the presence of hydroquinone (HQ) onto indium-tin-oxide-coated glass electrodes (glass/ITO) at potentials positive of the HQ oxidation potential. HQ oxidation produces protons at the electrode surface, which serve to neutralize the citrate molecules that electrostatically stabilize the Au NPs. Neutralization leads to the loss of stabilization and deposition onto the electrode. EPD in the presence of ferrocyanide, a non-proton-producing molecule, at oxidation potentials resulted in no deposition …


Selective Catalysis By Polymer-Supported Ruthenium Nanoparticlesand New Ligand Design For Cooperative And Bimetallic Catalysis, Seyed Hadi Nazari Mar 2019

Selective Catalysis By Polymer-Supported Ruthenium Nanoparticlesand New Ligand Design For Cooperative And Bimetallic Catalysis, Seyed Hadi Nazari

Theses and Dissertations

The abstract is the summary of three different projects all centered around the generalidea of catalysis which is the general theme of research in the Michaelis laboratory. The firstproject focuses on development of a new heterogeneous catalyst for selective catalysis. In theMichaelis lab, we were interested in the potential of nanoparticle catalysts for regioselectivetransformations. We showed that polymer supported ruthenium nanoparticles performed as areliable catalyst for regioselective reduction of azide to amine. In our study of regioselectivereduction of multiple azide containing substrates, we observed that in presence of ourruthenium nanoparticle catalysts, the least sterically hindered azide group reduced to aminefunctional …


Nanoscale Building Blocks: Bridging The Gap Between Potential And Realized Applications, Nicole Ritter Jan 2019

Nanoscale Building Blocks: Bridging The Gap Between Potential And Realized Applications, Nicole Ritter

Theses and Dissertations (Comprehensive)

The vast potential of nanoparticles and nanotechnology remains largely untapped; the crucial bottleneck being the knowledge gap between making and using nanoparticles (NPs). This PhD work bridges this gap by focusing on synthesizing nanoparticles with applications at the forefront. Four peer-reviewed publications are presented in Chapters 3-6, a safety and toxicological perspective is given in Chapter 7, and current work and future progress are summarized in Appendix 1. Bimorphic silver nanoparticles were prepared, presenting an innovative method to synthesize diverse nanostructures using polymeric surface blocking to break symmetry in seeded regrowth (Chapter 3).1 Silver stars with D5h symmetry …


Development And Characterization Of Ldv Peptide Targeted Nanocarriers For Paclitaxel Delivery: A Comparative Study Of Micelles, Liposomes And Solid Lipid Nanoparticles, Poonam Dattani Jan 2019

Development And Characterization Of Ldv Peptide Targeted Nanocarriers For Paclitaxel Delivery: A Comparative Study Of Micelles, Liposomes And Solid Lipid Nanoparticles, Poonam Dattani

University of the Pacific Theses and Dissertations

Nanocarriers have been established as delivery vehicles to target cancer tumors. However, premature drug leakage is one of the major reasons for inefficient drug delivery of nanocarriers to the tumor. Drug diffusion out of the nanocarriers or destabilization of drug loaded nanocarriers by physiological interactions with blood cells, serum proteins, and cell membranes upon systemic administration contribute to premature drug release. In this study, targeted micelles, liposomes and solid lipid nanoparticles (SLNs) of similar composition were prepared and characterized to compare physicochemical characteristics, in vitro stability, in vitro release rates in release media and in vivo performance. Peptide Amphiphiles (PAs) …