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Biomaterials

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Full-Text Articles in Nanoscience and Nanotechnology

The Effect Of Defects And Surface Modification On Biomolecular Assembly And Transport, Haneen Martinez Mar 2019

The Effect Of Defects And Surface Modification On Biomolecular Assembly And Transport, Haneen Martinez

Nanoscience and Microsystems ETDs

Nanoscale transport using the kinesin-microtubule (MT) biomolecular system has been successfully used in a wide range of nanotechnological applications including self-assembly, nanofluidic transport, and biosensing. Most of these applications use the ‘gliding motility geometry’, in which surface-adhered kinesin motors attach and propel MT filaments across the surface, a process driven by ATP hydrolysis. It has been demonstrated that active assembly facilitated by these biomolecular motors results in complex, non-equilibrium nanostructures currently unattainable through conventional self-assembly methods. In particular, MTs functionalized with biotin assemble into rings and spools upon introduction of streptavidin and/or streptavidin-coated nanoparticles. Upon closer examination of these ...


Towards The Rational Design And Application Of Polymers For Gene Therapy: Internalization And Intracellular Fate, Landon Alexander Mott Jan 2019

Towards The Rational Design And Application Of Polymers For Gene Therapy: Internalization And Intracellular Fate, Landon Alexander Mott

Theses and Dissertations--Chemical and Materials Engineering

Gene therapy is an approach for the treatment of acquired cancers, infectious disease, degenerative disease, and inherited genetic indications. Developments in the fields of immunotherapies and CRISPR/Cas9 genome editing are revitalizing the efforts to move gene therapy to the forefront of modern medicine. However, slow progress and poor clinical outcomes have plagued the field due to regulatory and safety concerns associated with the flagship delivery vector, the recombinant virus. Immunogenicity and poor transduction in certain cell types severely limits the utility of viruses as a delivery agent of nucleic acids. As a result, significant efforts are being made to ...


Chemically Modified Monolayer Surfaces Influence Valvular Interstitial Cell Attachment And Differentiation For Heart Valve Tissue Engineering, Matthew N. Rush Dec 2018

Chemically Modified Monolayer Surfaces Influence Valvular Interstitial Cell Attachment And Differentiation For Heart Valve Tissue Engineering, Matthew N. Rush

Nanoscience and Microsystems ETDs

As a cell mediated-process, valvular heart disease (VHD) results in significant morbidity and mortality world-wide. In the US alone, valvular heart disease VHD is estimated to affect 2.5% of the population with a disproportionate impact on an increasing elderly populous. It is well understood that the primary driver for valvular calcification is the differentiation of valvular interstitial cells (VICs) into an osteoblastic-like phenotype. However, the factors leading to the onset of osteoblastic-like VICs (obVICs) and resulting calcification are not fully understood and a more complete characterization of VIC differentiation and phenotypic change is required before treatment of valve disease ...


Soft-Microrobotics: The Manipulation Of Alginate Artificial Cells, Samuel Sheckman May 2018

Soft-Microrobotics: The Manipulation Of Alginate Artificial Cells, Samuel Sheckman

Mechanical Engineering Research Theses and Dissertations

In this work, the approach to the manipulation of alginate artificial cell soft-microrobots, both individually and in swarms is shown. Fabrication of these artificial cells were completed through centrifugation, producing large volumes of artificial cells, encapsulated with superparamagnetic iron oxide nanoparticles; these artificial cells can be then externally stimulated by an applied magnetic field. The construction of a Permeant Magnet Stage (PMS) was produced to manipulate the artificial cells individually and in swarms. The stage functionalizes the permanent magnet in the 2D xy-plane. Once the PMS was completed, Parallel self-assembly (Object Particle Computation) using swarms of artificial cells in complex ...


Fabrication And Modification Of Titania Nanotube Arrays For Harvesting Solar Energy And Drug Delivery Applications, Ahmed El Ruby Abdel Rahman Mohamed Dec 2017

Fabrication And Modification Of Titania Nanotube Arrays For Harvesting Solar Energy And Drug Delivery Applications, Ahmed El Ruby Abdel Rahman Mohamed

Electronic Thesis and Dissertation Repository

The fast diminishing of fossil fuels in the near future, as well as the global warming caused by increasing greenhouse gases have motivated the urgent quest to develop advanced materials as cost-effective photoanodes for solar light harvesting and many other photocatalytic applications. Recently, titania nanotube arrays (TNTAs) fabricated by anodization process has attracted great interest due to their excellent properties such as: high surface area, vertically oriented, highly organized, one-dimensional, nanotubular structure, photoactivity, chemical stability and biocompatibility. This unique combination of excellent properties makes TNTAs an excellent photoanode for solar light harvesting. However, the relatively wide band gap energy of ...


Activity Preservation Of Plasmonic Biosensors With A Metal-Organic Framework, Lu Wang Dec 2016

Activity Preservation Of Plasmonic Biosensors With A Metal-Organic Framework, Lu Wang

Engineering and Applied Science Theses & Dissertations

Antibody-antigen recognition enables antibody-conjugated nanostructures to serve as plasmonic biosensors with tunable specificity. However due to the instability of antibodies, these biosensors are susceptible to changes in the environment such as heat and aridity, leading to constraints on the transportation and handling of these sensors. Here we establish a method using a metal-organic framework crystal to preserve biosensor activity under severe environmental conditions, including exposure to high temperatures, an organic solvent and a proteolytic agent. After zeolitic imidazolate framework-8 (ZIF-8) crystals formed for 12 hours on a biosensor of gold nanorods conjugated with a model antibody, rabbit IgG, 80% of ...


Inter-Droplet Membranes For Mechanical Sensing Applications, Nima Tamaddoni Jahromi May 2016

Inter-Droplet Membranes For Mechanical Sensing Applications, Nima Tamaddoni Jahromi

Doctoral Dissertations

This dissertation combines self-assembly phenomena of amphiphilic molecules with soft materials to create and characterize mechanoelectrical transducers and sensors whose sensing elements are thin-film bioinspired membranes comprised of phospholipids or amphiphilic polymers. We show that the structures of these amphiphilic molecules tune the mechanical and electrical properties of these membranes. We show that these properties affect the mechanoelectrical sensing characteristic and range of operation of these membrane transducers. In the experiments, we construct and characterize a membrane-based hair cell embodiment that enables the membrane to be responsive to mechanical perturbations of the hair. The resulting oscillations of membranes formed between ...


Biomimetic Oral Mucin From Polymer Micelle Networks, Sundar Prasanth Authimoolam Jan 2015

Biomimetic Oral Mucin From Polymer Micelle Networks, Sundar Prasanth Authimoolam

Theses and Dissertations--Chemical and Materials Engineering

Mucin networks are formed by the complexation of bottlebrush-like mucin glycoprotein with other small molecule glycoproteins. These glycoproteins create nanoscale strands that then arrange into a nanoporous mesh. These networks play an important role in ensuring surface hydration, lubricity and barrier protection. In order to understand the functional behavior in mucin networks, it is important to decouple their chemical and physical effects responsible for generating the fundamental property-function relationship. To achieve this goal, we propose to develop a synthetic biomimetic mucin using a layer-by-layer (LBL) deposition approach. In this work, a hierarchical 3-dimensional structures resembling natural mucin networks was generated ...


Developent Of A Phospholipid Encapsulation Process For Quantum Dots To Be Used In Biologic Applications, Logan Grimes Jun 2014

Developent Of A Phospholipid Encapsulation Process For Quantum Dots To Be Used In Biologic Applications, Logan Grimes

Master's Theses and Project Reports

The American Cancer Society predicts that 1,665,540 people will be diagnosed with cancer, and 585,720 people will die from cancer in 2014. One of the most common types of cancer in the United States is skin cancer. Melanoma alone is predicted to account for 10,000 of the cancer related deaths in 2014. As a highly mobile and aggressive form of cancer, melanoma is difficult to fight once it has metastasized through the body. Early detection in such varieties of cancer is critical in improving survival rates in afflicted patients. Present methods of detection rely on visual ...


Oriented Collagen And Applications Of Waveguide Evanescent Field Scattering (Wefs) Microscopy, Qamrun Nahar Apr 2014

Oriented Collagen And Applications Of Waveguide Evanescent Field Scattering (Wefs) Microscopy, Qamrun Nahar

Electronic Thesis and Dissertation Repository

In this thesis, Waveguide Evanescent Field Scattering (WEFS) microscopy is developed as a non-invasive, label-free live cell imaging technique. This new high-contrast imaging can be employed to study the first hundred nanometers from the surface as it utilizes the evanescent field of a waveguide as the illumination source. Previously, waveguide evanescent field fluorescence (WEFF) microscopy was developed as a fluorescence imaging technique comparable to the total internal reflection fluorescent (TIRF) microscopy. Both the WEFF and WEFS technique utilizes the same fundamental concepts except in WEFS microscopy imaging is accomplished without the application of any fluorescent labeling. In this work, bacterial ...


Fluorescence Characterization Of Quantum Dots For Use As Biomarkers, Logan M. Grimes Jun 2013

Fluorescence Characterization Of Quantum Dots For Use As Biomarkers, Logan M. Grimes

Materials Engineering

Fluorescence profiles of quantum dots (QDs) were characterized to select the ideal QDs for encapsulation in phospholipids for use as biomarkers to selectively adhere to cancer cells. QDs were synthesized and extracted 0, 30, 60, and 90 seconds after precursor compounds were mixed. These extractions were isolated by extraction time. Portions from each vial were coated in a zinc sulfide shelling procedure, leaving at least half of the QD solution unshelled. These samples were characterized over four days to monitor fluctuations in fluorescence. This was done utilizing an Ocean Optics spectrometer in conjunction with Spectra Suite software. The central wavelength ...


Femtosecond Laser Patterned Templates And Imprinted Polymer Structures, Deepak Rajput May 2013

Femtosecond Laser Patterned Templates And Imprinted Polymer Structures, Deepak Rajput

Doctoral Dissertations

Femtosecond laser machining is a direct-write lithography technique by which user-defined patterns are efficiently and rapidly generated at the surface or within the bulk of transparent materials. When femtosecond laser machining is performed with tightly focused amplified pulses in single-pulse mode, transparent substrates like fused silica can be surface patterned with high aspect ratio (>10:1) and deep (>10 μm) nanoholes. The main objective behind this dissertation is to develop single-pulse amplified femtosecond laser machining into a novel technique for the production of fused silica templates with user-defined patterns made of high aspect ratio nanoholes. The size of the nanoholes ...


Encapsulation And Controlled Release Of Rhu-Erythropoietin From Chitosan Biopolymer Nanoparticles, Cody Bulmer Apr 2012

Encapsulation And Controlled Release Of Rhu-Erythropoietin From Chitosan Biopolymer Nanoparticles, Cody Bulmer

Electronic Thesis and Dissertation Repository

The objective of this research project was to develop a drug delivery system for recombinant human erythropoietin (rHu-EPO), a glycoprotein hormone used in the treatment of renal anaemia and chemotherapy induced anaemia, using the biopolymer chitosan as the base component. Two types of chitosan nanoparticles were produced through ionotropic gelation using flush mixing with either tripolyphosphate (TPP) or carrageenan polymer. Chitosan-TPP and chitosan-carrageenan nanoparticles were generated under a variety of conditions to evaluate the effects of chitosan concentration, chitosan to anion mass ratio and solution pH on the nanoparticle characteristics of particle diameter, surface charge and particle size distribution. A ...


Monitoring Of Immune Cell Response To B Cell Depletion Therapy And Nerve Root Injury Using Spio Enhanced Mri, Daniel L. Thorek Dec 2009

Monitoring Of Immune Cell Response To B Cell Depletion Therapy And Nerve Root Injury Using Spio Enhanced Mri, Daniel L. Thorek

Publicly Accessible Penn Dissertations

Magnetic resonance (MR) is a robust platform for non-invasive, high-resolution anatomical imaging. However, MR imaging lacks the requisite sensitivity and contrast for imaging at the cellular level. This represents a clinical impediment to greater diagnostic accuracy. Recent advances have allowed for the in vivo visualization of populations and even of individual cells using superparamagnetic iron oxide (SPIO) MR contrast agents. These nanoparticles, commonly manifested as a core of a single iron oxide crystal or cluster of crystals coated in a biocompatible shell, function to shorten proton relaxation times. In MR imaging these constructs locally dephase protons, resulting in a decrease ...