Physical Sciences and Mathematics Commons^™

Studies On Silicon Nmr Characterization And Kinetic Modeling Of The Structural Evolution Of Siloxane-Based Materials And Their Applications In Drug Delivery And Adsorption, Jyotrhirmai Ambati

University of Kentucky Doctoral Dissertations

This dissertation presents studies of the synthetic processes and applications of siloxane-based materials. Kinetic investigations of bridged organoalkoxysilanes that are precursors to organic-inorganic hybrid polysilsesquioxanes are a primary focus. Quick gelation despite extensive cyclization is found during the polymerization of bridged silane precursors except for silanes with certain short bridges. This work is an attempt to characterize and understand some of the distinct features of bridged silanes using experimental characterization, kinetic modeling and simulation. In addition to this, the dissertation shows how the properties of siloxane- materials can be engineered for drug delivery and adsorption.

The phase behavior of polymerizing …

Novel Solution Processable Acceptors For Organic Photovoltaic Applications, Ying Shu

University of Kentucky Doctoral Dissertations

The field of organic electronics has become an increasingly important field of research in recent years. Organic based semiconductors have the potential for creating inexpensive, solution processed devices on flexible substrates. Some of the applications of organic semiconductors include organic field effect transistors, organic light emitting diodes and organic photovoltaics.

Functionalized pentacenes have been proven to be viable donor materials for use in organic photovoltaic devices. The goal of this research is to synthesize and test the viability of novel electron deficient pentacenes and pentacene based materials as acceptors to be used as drop-in replacements for PCBM in bulk-heterojunction organic …

Interactions And Effects Of Biomolecules On Au Nanomaterial Surfaces, Manish Sethi

University of Kentucky Doctoral Dissertations

Au nanoparticles are increasingly being used in biological applications. Their use is of interest based upon their unique properties that are achieved at the nanoscale, which includes strong optical absorbances that are size and aggregation state dependent. Such absorbances can be used in sensitive chemical/biological detection schemes where bioligands can be directly attached to the nanoparticle surface using facile methods. Unfortunately, a number of complications persist that prevent their wide-scale use. These limitations include minimal nanoparticle stability in biological-based media of high ionic strength, unknown surface functionalization effects using simple biomolecules, and determining the binding motifs of the ligands to …

Partially Halogenated Acenes And Heteroacenes For Organic Electronics, Balaji Purushothaman

University of Kentucky Doctoral Dissertations

Inorganic materials have dominated electronic applications such as photovoltaic cells, thin film transistors (TFTs) and light emitting diodes (LEDs). However developments in the field of organic electronics over the past three decades have enabled the use of organic materials in these devices. While significant improvements have been made to improve their electronic properties there are several road blocks towards commercial application. One of the significant obstacles is the poor charge carrier mobility associated with organic semiconductors processed by well established printing methods. The goal of my research project is to improve the charge carrier mobility of solution cast films of …

Evaluation Of The Physicochemical Properties And Stability Of Solid Lipid Nanoparticles Designed For The Delivery Of Dexamethasone To Tumors, Melissa Howard

University of Kentucky Doctoral Dissertations

Pre-clinical and clinical trials suggest that pre-treatment with dexamethasone (Dex) may facilitate enhanced uptake of subsequently administered chemotherapeutic agents. To reduce the side effects associated with systemic administration of Dex, solid lipid nanoparticles (SLNs) containing dexamethasone palmitate (Dex-P) were prepared as a means of achieving tumor-targeted drug delivery. These studies were aimed at evaluating the physicochemical properties and both the physiological and storage stability of the SLNs.

SLNs were prepared using nanotemplate engineering technology. Stearyl alcohol (SA) was used as the lipid phase with Brij^® 78 and Polysorbate 60 as surfactants and PEG6000 monostearate as a long-chain PEGylating agent. …

Fabrication And Characterization Of Mesoscale Protein Patterns Using Atomic Force Microscopy (Afm), Pei Gao

University of Kentucky Doctoral Dissertations

A versatile AFM local oxidation lithography was developed for fabricating clean protein patterns ranging from nanometer to sub-millimeter scale on octadecyltrichlorosilane (OTS) layer of Si (100) wafer. This protein patterning method can generate bio-active protein pattern with a clean background without the need of the anti-fouling the surface or repetitive rinsing.

As a model system, lysozyme protein patterns were investigated through their binding reactions with antibodies and aptamers by AFM. Polyclonal anti-lysozyme antibodies and anti-lysozyme aptamer are found to preferentially bind to the lysozyme molecules on the edge of a protein pattern before their binding to the interior ones. It …

Periodic Trends In Structure Function Relationship Of Organic Heteroacenes, Marsha Loth Grimminger

University of Kentucky Doctoral Dissertations

Our group has previously shown that small changes to molecular structure result in large changes to device properties and stability in organic electronic applications. By functionalizing aromatic heteroacenes with group 14 and group 16 elements, it is possible to control morphology and improve stability for a variety of applications such as thin film transistors and solar cells. Functionalization within the heteroacene core led to changes in electronic structure as observed by electrochemistry and light absorption. By substituting down the periodic table, the carbon heteroatom bond length increased, leading to subtle changes in crystal packing. Absorption maxima were red-­‐shifted and stability …