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Photothermal And Photochemical Strategies For Lightinduced Shape-Morphing Of Soft Materials, Alexa Simone Kuenstler Dec 2020

Photothermal And Photochemical Strategies For Lightinduced Shape-Morphing Of Soft Materials, Alexa Simone Kuenstler

Doctoral Dissertations

Engineering materials with the capability to transform energy from photons into mechanical work is an outstanding technical challenge with implications across myriad disciplines. Despite decades of work in this area, comprehensive understanding of how to prescribe shape change and work output in photoactive systems remains limited. To this end, this dissertation explores strategies to assemble photothermal and photochemical moieties in soft material systems to fabricate photoaddressable devices capable of specific shape changes upon illumination. Chapters 2 and 3 describe a methodology for spatially patterning plasmonic nanoparticles in liquid crystal elastomer fibers and sheets to specify local photothermally-induced strain profiles. Using …


Engineering Stimuli-Responsive Polymeric Nanoassemblies: Rational Designs For Intracellular Delivery Of Biologics, Kingshuk Dutta Dec 2020

Engineering Stimuli-Responsive Polymeric Nanoassemblies: Rational Designs For Intracellular Delivery Of Biologics, Kingshuk Dutta

Doctoral Dissertations

Biologic drugs have gained enormous research attention in recent years as reflected by the development of multiple candidates to the clinical pipelines and an increased percentage of FDA approval. This is reasoned by the fact that biologics have been proven to deliver more predictive and promising benefits for many hard-to-cure diseases by ‘drugging the undruggable’ targets. However, the challenges associated with biologic drug development are multi-fold, viz, poor encapsulation efficacy, systemic instability, low cellular internalization and endosomal escape capability. Thus, it is essential to develop new molecular strategies that can not only address the associated drug delivery challenges, but also …


Engineered Proteins As Tools To Understand Ubiquitin Signaling, Lin Hui Chang Dec 2020

Engineered Proteins As Tools To Understand Ubiquitin Signaling, Lin Hui Chang

Doctoral Dissertations

Ubiquitin is a 76 amino acids protein that is evolutionary conserved in eukaryotes. It is an important signaling molecule in a plethora biological events, such as protein degradation, DNA damage response, and transcription. This thesis aims to develop engineered protein as a tool to study ubiquitin signaling. Through targeted mutagenesis and directed evolution, a deubiquitinase is reprogrammed into a transamidase, which lead to the generation of ubiquitinprotein conjugates with discrete ubiquitin linkages through auto-ubiquitination. These ubiquitin-protein conjugates could be used as a model substrate to profile their interaction of different ubiquitin interacting proteins. In addition, using directed evolution and deep …


Theory And Improved Methods For Probing The Cavitation To Fracture Transition, Christopher Barney Dec 2020

Theory And Improved Methods For Probing The Cavitation To Fracture Transition, Christopher Barney

Doctoral Dissertations

A material is considered soft when its bulk modulus is significantly greater than its shear modulus. Rubbery polymers are a class of soft materials where resistance to extension is mainly entropic in nature. Polymeric soft solids differ from liquids due to the presence of a percolated network of strong bonds that resist deformation and flow on a given time scale. The incompressible nature, entropically driven elasticity, and molecular scale network structure of soft polymeric solids combine to impart unique mechanical behavior that often results in complex material responses to simple loading situations. An important example of this is cavitation in …


Investigating The Accumulation, Sub-Organ Distribution, And Biochemical Effects Of Nanomaterials Using Mass Spectrometry, Kristen Nicole Sikora Dec 2020

Investigating The Accumulation, Sub-Organ Distribution, And Biochemical Effects Of Nanomaterials Using Mass Spectrometry, Kristen Nicole Sikora

Doctoral Dissertations

Gold nanoparticles (AuNPs) are attractive materials for use in various biomedical applications, such as therapeutic delivery, due to their unique chemical properties and modular tunability. Mass spectrometry methods, including laser desorption/ionization mass spectrometry (LDI-MS) and inductively coupled plasma mass spectrometry (ICP-MS) have been successfully used to evaluate the distribution of AuNPs in complex biological systems. As new AuNP-based materials are developed for applications in therapeutic delivery, it is essential to simultaneously develop analytical techniques that can comprehensively assess their behavior in vivo. In this dissertation, novel mass spectrometric methods have been developed and utilized to evaluate the uptake, distribution, …


Analysis Of Titanium Dioxide Nanoparticles In Foods Using Raman Spectroscopic Techniques, Janamkumar Pandya Dec 2020

Analysis Of Titanium Dioxide Nanoparticles In Foods Using Raman Spectroscopic Techniques, Janamkumar Pandya

Doctoral Dissertations

Titanium dioxide (TiO2) and its nanoparticles (NPs) are widely used in various applications. Recently, the presence of TiO2 NPs in food and consumer products raised safety concerns to human health and the environment. The goal of this project is to explore the capability of Raman Spectroscopy in the analysis of TiO2-NPs and apply this technique for the analysis of TiO2-NPs in food and environmental samples. Two approaches, i.e. the ligand-based and the mapping-based, were evaluated. The ligand-based approach utilized the surface enhanced Raman scattering (SERS) property of the TiO2 NPs as a substrate to enhance the signal of a surface …


Study Of The Role Of Biologically-Relevant, Labile Nickel Pools In The Maturation Of Nickel-Dependent Enzymes, Priyanka Basak Sep 2020

Study Of The Role Of Biologically-Relevant, Labile Nickel Pools In The Maturation Of Nickel-Dependent Enzymes, Priyanka Basak

Doctoral Dissertations

Cellular nickel pools, comprised of static and labile pools of nickel complexes, play important roles in maintaining nickel homeostasis in various organisms (microbes, fungi, and plants), which utilize it as a cofactor of one or more nickel enzymes that catalyze specific reactions and are essential for their proper growth and survival in various ecological niches. Like other metals, tight regulation of cellular nickel levels is critical to prevent toxic effects of nickel deprivation, nickel overload, and ‘free’ nickel. While more static nickel pools include nickel tightly bound to nickel-dependent enzymes, nickel in the labile pool is exchangeable and weakly bound …


Chemical Manipulation Of Macrophages: Nanomaterial And Molecular Approaches, Joseph Hardie Jul 2020

Chemical Manipulation Of Macrophages: Nanomaterial And Molecular Approaches, Joseph Hardie

Doctoral Dissertations

Macrophages, phagocytic cells of the innate immune system, are the body’s first line of defense against pathogens and are responsible for tissue maintenance. Macrophages are capable of sensing and internalizing external stimuli, and in response change their morphology and phenotype accordingly. Because macrophages are integral to immune function and tissue maintenance, dysregulation of macrophage behavior is associated with a range of diseases including infections, cancer, autoimmune disorders, atherosclerosis, and more. Because of the implications of macrophage failure, there is interest in creating new materials to manipulate macrophage behavior for a therapeutic effect. In this thesis, I describe the application of …


Structural Analysis Of Protein Therapeutics Using Covalent Labeling – Mass Spectrometry, Patanachai Limpikirati Jul 2020

Structural Analysis Of Protein Therapeutics Using Covalent Labeling – Mass Spectrometry, Patanachai Limpikirati

Doctoral Dissertations

Using mass spectrometry (MS) to obtain information about a higher order structure of protein requires that a protein’s structural properties are encoded into the mass of that protein. Covalent labeling (CL) with reagents that can irreversibly modify solvent accessible amino acid side chains is an effective way to encode structural information into the mass of a protein, as this information can be read-out in a straightforward manner using standard MS-based proteomics techniques. The differential reactivity of proteins under two or more conditions can be used to distinguish protein topologies, conformations, and/or binding sites. CL-MS methods have been effectively used for …


Characterization Of Biodistribution Of Transferrin And Receptor Binding Mechanism By Mass Spectrometry, Hanwei Zhao Mar 2020

Characterization Of Biodistribution Of Transferrin And Receptor Binding Mechanism By Mass Spectrometry, Hanwei Zhao

Doctoral Dissertations

Protein-based therapeutics have emerged as a key driver of rapid growth in drug development pipelines. However, developing such protein drugs is not straightforward in most cases, the existence of physiological barriers greatly restricts the efficient delivery of many therapeutic molecules, and therefore limits their clinical applications. A promising way to address this challenge takes advantage of certain transport protein which can effectively across and enhance the permeability of these barriers, such as transferrin (Tf) which can be internalized by malignant cells and cross physiological barriers via transferrin receptor (TfR)-mediated endocytosis and transcytosis. However, developing such products is impossible without successfully …


Modulating Nanoparticle-Protein Interactions Through Covalent Or Noncovalent Approach For Biomedical Applications, Jingjing Gao Mar 2020

Modulating Nanoparticle-Protein Interactions Through Covalent Or Noncovalent Approach For Biomedical Applications, Jingjing Gao

Doctoral Dissertations

Discoveries at the interface of chemistry, biology, and materials science have emerged as a powerful route to impact life science in this century. My research in the Thayumanavan group is focused on problems at this interface. A common theme of all the six projects is the use of modern synthetic organic chemistry to build interesting, novel macromolecules which are chemically rich, to study the molecular self-assembly behavior in solution and then translate to solve problems in the biomedical area. By addressing the design challenge to prepare novel amphiphiles with desired functional groups, controlled molecular weight and the ability to respond …


Powering Advances In Next-Generation Photovoltaics Through Materials Synthesis And Characterization, Christie L.C. Ellis Mar 2020

Powering Advances In Next-Generation Photovoltaics Through Materials Synthesis And Characterization, Christie L.C. Ellis

Doctoral Dissertations

Solar energy is our most abundant natural resource: the energy from sunlight that strikes the Earth in one hour is more than the energy consumed globally in a year. This makes photovoltaics, which convert solar energy into electrical energy, a critical technology to pursue. 95% of the photovoltaic market is dominated by silicon; its high efficiency, stability, and plummeting manufacturing costs made it the clear choice for commercialization. However, silicon solar cells are thick, heavy, opaque, and rigid, limiting potential applications. They are energy- and resource-intensive to produce, and their manufacturing process uses and produces several toxic substances. “Next-generation” photovoltaic …


Molecular Design Of Organic Semiconductors For Interfacial And Emissive Material Applications, Marcus David Cole Mar 2020

Molecular Design Of Organic Semiconductors For Interfacial And Emissive Material Applications, Marcus David Cole

Doctoral Dissertations

This dissertation describes the synthesis and characterization of functional optoelectronically active materials. Synthetic techniques were used to prepare polymers containing perylene diimide (PDI) or tetraphenylethylene (TPE) moieties in the polymer backbone. PDI-based structures were prepared with embedded cationic or zwitterionic moieties intended to tailor organic/inorganic interfaces in thin film photovoltaic devices. The aggregation-induced emission (AIE)-active TPE polymers were synthesized to study how AIE properties evolve in π-conjugated polymers. The syntheses discussed here focused on modulation of molecular architecture to give rise to materials with tailored optoelectronic properties. Chapter 1 provides a brief overview of the field of organic electronics and …


Covalent Labeling-Mass Spectrometry For Characterizing Protein-Ligand Complexes, Tianying Liu Feb 2020

Covalent Labeling-Mass Spectrometry For Characterizing Protein-Ligand Complexes, Tianying Liu

Doctoral Dissertations

This dissertation focuses on applying covalent labeling (CL) and mass spectrometry (MS) for characterizing protein-ligand complexes. Understanding protein-ligand interactions has both fundamental and applied significance. Covalent labeling is a protein surface modification technique that selectively modifies solvent-exposed amino acid side chains of proteins. A covalent bond is formed between the functional groups of labeling reagent and protein’s side chain. One of the key factors that affects CL reactivity is a side chain’s solvent accessibility. Ligand binding protects residues on the protein surface from being labeled, and residues involved in ligand binding can be indicated via decreases in labeling extents. The …