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Full-Text Articles in Nanoscience and Nanotechnology

Two-Dimensional Nanopore And Nanoporous Devices For Molecular Sensing And Ion Selectivity, Gopinath Danda Jan 2018

Two-Dimensional Nanopore And Nanoporous Devices For Molecular Sensing And Ion Selectivity, Gopinath Danda

Publicly Accessible Penn Dissertations

Nanopore-based devices provide the ability to detect, analyze and manipulate molecules by monitoring changes in ionic current and sieving molecules dissolved in an electrolyte. While devices with single nanopores can be used as molecular sensors and analyzers, including as a possible high-throughput DNA sequencer, devices with multiple nanopores (nanoporous devices) can be used to filter out ions from solutions, with possible use in water desalination. Sensitivity and molecular flux can be enhanced by using two-dimensional (2D) materials, like graphene and transition metal dichalcogenides (TMDs), as the nanopore membrane. However, these devices face challenges yet to be solved, including (a) fast ...


Design And Synthesis Of Gold Nanoparticle Contrast Agents For Atherosclerosis Imaging With Computed Tomography, Peter Chhour Jan 2017

Design And Synthesis Of Gold Nanoparticle Contrast Agents For Atherosclerosis Imaging With Computed Tomography, Peter Chhour

Publicly Accessible Penn Dissertations

Cell tracking offers the opportunity to study migration and localization of cells in vivo, allowing investigations of disease mechanisms and drug efficacy. Monocytes play a key role in the progression of atherosclerotic plaques in the coronary arteries. While x-ray computed tomography (CT) is commonly used to clinically assess coronary plaque burden, cell tracking with CT is mostly unexplored. The establishment of monocyte cell tracking tools would allow for the direct investigation of gene and drug therapies aimed at monocyte recruitment in atherosclerosis. In this thesis, we present the design and optimization of gold nanoparticles as CT contrast agents for cell ...


Flexible, Photopatterned, Colloidal Cdse Semiconductor Nanocrystal Integrated Circuits, Franklin Scott Stinner Jan 2017

Flexible, Photopatterned, Colloidal Cdse Semiconductor Nanocrystal Integrated Circuits, Franklin Scott Stinner

Publicly Accessible Penn Dissertations

As semiconductor manufacturing pushes towards smaller and faster transistors, a parallel goal exists to create transistors which are not nearly as small. These transistors are not intended to match the performance of traditional crystalline semiconductors; they are designed to be significantly lower in cost and manufactured using methods that can make them physically flexible for applications where form is more important than speed. One of the developing technologies for this application is semiconductor nanocrystals.

We first explore methods to develop CdSe nanocrystal semiconducting “inks” into large-scale, high-speed integrated circuits. We demonstrate photopatterned transistors with mobilities of 10 cm2/Vs on ...


A Novel Needleless Liquid Jet Injection Methodology For Improving Direct Cardiac Gene Delivery: An Optimization Of Parameters, Aav Mediated Therapy And Investigation Of Host Responses In Ischemic Heart Failure, Anthony Samuel Fargnoli Jan 2014

A Novel Needleless Liquid Jet Injection Methodology For Improving Direct Cardiac Gene Delivery: An Optimization Of Parameters, Aav Mediated Therapy And Investigation Of Host Responses In Ischemic Heart Failure, Anthony Samuel Fargnoli

Publicly Accessible Penn Dissertations

Heart disease remains the leading cause of mortality and morbidity worldwide, with 22 million new patients diagnosed annually. Essentially, all present therapies have significant cost burden to the healthcare system, yet fail to increase survival rates. One key employed strategy is the genetic reprogramming of cells to increase contractility via gene therapy, which has advanced to Phase IIb Clinical Trials for advanced heart failure patients. It has been argued that the most significant barrier preventing FDA approval are resolving problems with safe, efficient myocardial delivery, whereby direct injection in the infarct and remote tissue areas is not clinically feasible. Here ...


Designing Nanomaterials For Electronic And Optoelectronic Devices Through Charge Carrier Control, Soong Ju Oh Jan 2014

Designing Nanomaterials For Electronic And Optoelectronic Devices Through Charge Carrier Control, Soong Ju Oh

Publicly Accessible Penn Dissertations

Colloidal semiconductor nanocrystals (NCs) have been shown to be promising materials for electronic and optoelectronic device applications because of their unique size-dependent properties and low-cost solution processability. However, the integration of these materials into devices has been challenging due to a lack of available methods to: 1) accurately control charge carrier statistics, such as majority carrier type and concentration, and carrier mobilities, and 2) efficiently passivate surface defects inherent in NC materials arising from their high surface-volume ratio.

In this thesis, we study the fundamental physics of charge carriers paramount for device application. Then, we introduce several measurement techniques to ...


Flexible Electronics Based On Solution Processable Organic Semiconductors And Colloidal Semiconductor Nanocrystals, Yuming Lai Jan 2014

Flexible Electronics Based On Solution Processable Organic Semiconductors And Colloidal Semiconductor Nanocrystals, Yuming Lai

Publicly Accessible Penn Dissertations

Solution-processable semiconductors hold great potential for the large-area, low-cost fabrication of flexible electronics. Recent advances in flexible electronics have introduced new functional devices such as light-weight displays and conformal sensors. However, key challenges remain to develop flexible devices from emerging materials that use simple fabrication processes and have high-performance.

In this thesis, we first use a solution-processable organic semiconductor to build field-effect transistors on large-area plastic with mobility of 0.1 cm^2/Vs. Combined with passive components, we are able to build voltage amplifiers to capture few mV amplitude bio-signals. This work provides a proof of concept on applying ...


Virus-Size Nanoparticles Coated With A Synthetic "Self" Peptide Inhibit Phagocytic Clearance And Enhance Delivery Of An Anti-Cancer Drug, Pia Lorena Rodriguez Nunez Jan 2012

Virus-Size Nanoparticles Coated With A Synthetic "Self" Peptide Inhibit Phagocytic Clearance And Enhance Delivery Of An Anti-Cancer Drug, Pia Lorena Rodriguez Nunez

Publicly Accessible Penn Dissertations

Professional phagocytes are white blood cells of the innate immune system that protect humans and other animals from attacks by foreign pathogens by ingesting potentially harmful circulating particles. However, phagocytes such as macrophages may also attack elements that have been intentionally introduced into the body, such as implants, artificial tissues, artificial organs and vesicles bearing therapeutic agents, reducing their lifetime in the body. Nanoparticles and liposomes are similar in size to viruses, and are frequently decorated with antibodies for targeted therapeutics or imaging purposes. Although such particles are sufficiently small to avoid passive entrapment within capillaries in vivo, macrophages in ...


The Nanoaquarium: A Nanofluidic Platform For In Situ Transmission Electron Microscopy In Liquid Media, Joseph M. Grogan Dec 2011

The Nanoaquarium: A Nanofluidic Platform For In Situ Transmission Electron Microscopy In Liquid Media, Joseph M. Grogan

Publicly Accessible Penn Dissertations

There are many scientifically interesting and technologically relevant nanoscale phenomena that take place in liquid media. Examples include aggregation and assembly of nanoparticles; colloidal crystal formation; liquid phase growth of structures such as nanowires; electrochemical deposition and etching for fabrication processes and battery applications; interfacial phenomena; boiling and cavitation; and biological interactions. Understanding of these fields would benefit greatly from real-time, in situ transmission electron microscope (TEM) imaging with nanoscale resolution. Most liquids cannot be imaged by traditional TEM due to evaporation in the high vacuum environment and the requirement that samples be very thin. Liquid-cell in situ TEM has ...


Size-Dependent Metal-Insulator Transition In Pt-Dispersed Sio2 Thin Film: A Candidate For Future Non-Volatile Memory, Albert B. Chen Aug 2011

Size-Dependent Metal-Insulator Transition In Pt-Dispersed Sio2 Thin Film: A Candidate For Future Non-Volatile Memory, Albert B. Chen

Publicly Accessible Penn Dissertations

Non-volatile random access memories (NVRAM) are promising data storage and processing devices. Various NVRAM, such as FeRAM and MRAM, have been studied in the past. But resistance switching random access memory (RRAM) has demonstrated the most potential for replacing flash memory in use today. In this dissertation, a novel RRAM material design that relies upon an electronic transition, rather than a phase change (as in chalcogenide Ovonic RRAM) or a structural change (such in oxide and halide filamentary RRAM), is investigated. Since the design is not limited to a single material but applicable to general combinations of metals and insulators ...


Microbiorobots For Single Cell Manipulation, Mahmut Selman Sakar Nov 2010

Microbiorobots For Single Cell Manipulation, Mahmut Selman Sakar

Publicly Accessible Penn Dissertations

One of the great challenges in nano and micro scale science and engineering is the independent manipulation of biological cells and small man-made objects with active sensing. For such biomedical applications as single cell manipulation, telemetry, and localized targeted delivery of chemicals, it is important to fabricate microstructures that can be powered and controlled without a tether in fluidic environments. These microstructures can be used to develop microrobots that have the potential to make existing therapeutic and diagnostic procedures less invasive.

Actuation can be realized using various different organic and inorganic methods. Previous studies explored different forms of actuation and ...