Small molecules such as indanes, chromanes, tetralins and their derivatives play a significant role in drug discovery due to their potent biological activity. This research herein presents a facile Brønsted acid-catalyzed allylsilane annulation methodology to generate fused ring systems such as indanes. The reaction goes through a homoallylic intermediate which...
Self-assembled monolayers as tunable chemical platforms broadly enable the study of the interaction between biological species and synthetic surfaces. Unlike small molecule chemistry where the freely diffusible product can interact with biological targets as an inhibitor or probe, interfacial chemistry allows for the controlled and multi-valent presentation of ligands to...
Photovoltaic technology can help meet the exploding world energy demand in a sustainable and environmentally friendly way. Organic photovoltaics (OPVs) are especially attractive because they can be constructed with low-cost organic content and are amenable to high-throughput large-scale fabrication techniques. Synthetic modification of organic semiconductors has paved way for the...
My research interests, which span organic, inorganic, physical and biochemistry, have focused broadly on photo-, magneto- and redox-active molecules, especially those with potential applications in organic photovoltaics, spintronics and electronics. My research under the joint supervision of Professor Wasielewski and Professor Fraser Stoddart has concentrated upon understanding electronic and magnetic...
The utilization of hydrofluoric acid for the preparation of silver vanadium oxide fluorides has been advanced for the synthesis of Ag<sub>4</sub>V<sub>2</sub>O<sub>6</sub>F<sub>2</sub> and Ag<sub>3</sub>VO<sub>2</sub>F<sub>4</sub>. Silver-rich metal oxide fluorides are important battery cathode materials due to the high reduction potential of silver vs. Li, which is made even higher by the incorporation...
Assembly of the large and small subunits of the <em>E. coli</em> ribosome is a complicated process that involves transcription, processing, and modifying of the ribosomal RNA, the binding of ribosomal proteins, and the folding of the particles into complex structures. A number of ribosome assembly factors, including maturation factors, GTPases,...
The need for readily synthesized scaffold architectures to build monodisperse, high molar mass mobility modifiers or "drag-tags" in end-labeled free solution electrophoresis (ELFSE) led to the development of a novel class of multivalent molecular tools. Poly-N-substituted glycines (peptoids) were created with evenly spaced amino groups as branching points along the...
Organic light emitting diodes (OLEDs) are fabricated and characterized on anodes modified by a variety of surface treatments. OLED performance response is correlated to the treatment conditions with current-voltage (I-V) measurements and impedance spectroscopy. Small-scale OLED arrays are fabricated using a novel shadow mask approach and are characterized with electrical...
Theoretical analysis of DNA bridge-mediated electron transfer (ET) led to the proposal that photoinduced ET might occur via either superexchange or hopping mechanisms. Electron transfer has been proposed to occur via a superexchange mechanism at short distances and via a hopping mechanism at longer distances. However, a crossover in mechanism...
This dissertation describes the use of alkanethiols and polymers for the development of lithographic affinity and resist array templates that can be utilized for directing the assembly of biological molecules, for building up multilayered polyelectrolyte thin films, and for fabricating metal solid-state nanostructures. The first two chapters of the work...
The work presented in this thesis describes investigations into linear and nonlinear optical properties of two-dimensional silver nanoparticle arrays. The linear optical measurements - extinction measurements were performed on two-dimensional square arrays of L-shaped silver nanoparticles fabricated by electron beam lithography in order to study the effect of dipole coupling...
The first section of this thesis focuses on applications of DNA-modified gold nanoparticles (AuNPs) while the second part addresses the fundamental properties that arise from conjugating DNA to inorganic AuNPs. Two types of applications are discussed. The first application utilizes the colorimetric properties of AuNPs to screen duplex and triplex...
The overarching theme of this thesis is the development of non-natural oligomers for use in biological applications. Chapter I details the synthesis and studies of modified peptide nucleic acid (PNA) oligomers. PNA is a synthetic oligonucleotide mimic that binds to natural nucleic acids with extremely high affinity and specificity, making...
This dissertation describes the invention and development of a new nanolithographic method: On-Wire Lithography (OWL). OWL is a simple, reproducible, and high-throughput procedure for the synthesis and lithographic processing of metal nanowires (i.e. Au, Ag, Pt, Ni, and Cu) that allows researchers to control the morphology and feature size of...
Surfaces and interfaces, which are ubiquitous in the environment, control the mobility,speciation, and ultimate fate of groundwater species. The presented work provides insight into the interfacial behavior of three environmental pollutants: hexavalent chromium, oxytetracycline, and morantel. Model surfaces are employed for these studies, including (1-102) α-Al<sub>2</sub>O<sub>3</sub> and a carboxylic acid-terminated...
Direct dynamics quasiclassical trajectory (QCT) calculations are performed to study the dynamics of model atom + polyatom reactions. In the first part of this thesis, we examine adiabatic dynamics of H/O reaction with simple alkanes, CD4 and C2H6. Overall good agreement with state-of-the-art experiments shows that the molecular motion is...
This dissertation covers the synthesis and study of peptide nucleic acids (PNAs), specifically, derivatives of PNA containing amine-bearing sidechains or cyclopentane portions. PNAs are non-natural nucleic acids that have far reaching potential in therapeutics and nucleic acid detection. Despite immense potential and widespread application, improving on the design and applications...
Alkenylsilanes of varying chain lengths are investigated as simultaneous chain transfer agents + comonomers in organotitanium-mediated olefin polymerization processes. Ethylene + alkenylsilane polymerizations were carried out with activated Me2Si(Me4C5)(NtBu)TiMe2 and (-CH2CH2-3,3'){(5-indenyl )[1-Me2Si(tBuN)]}2Ti2Me4 precatalysts. Alkenylsilane incorporation levels follow the trend C8H15SiH3 < C6H11SiH3 ≈ C4H7SiH3 < C3H5SiH3. Long-chain branching levels versus...
Nanoplasmonics is an emerging branch of photonics that studies the optical properties of noble metals. Nanostructured noble metal materials, which can strongly interact with light and support various plasmon modes, are exceptional candidates for nanophotonic devices. This work describes the latest advances in the fabrication of ordered silver nanoparticles or...
The work presented here describes investigations into the optical properties of single silver nanoparticles. The contents of this thesis are divided into two parts: (1) single nanoparticle localized surface plasmon resonance (LSPR) spectroscopy and sensing and (2) approaches to combining LSPR spectroscopy with atomic force and transmission electron microscopies. Part...