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Full-Text Articles in Nanoscience and Nanotechnology

Pamam- Cyclodextrin Conjugate Upregulates Brain-Derived Neurotropic Factor In Arpe-19 Cells, Gopika Ashokan Mar 2023

Pamam- Cyclodextrin Conjugate Upregulates Brain-Derived Neurotropic Factor In Arpe-19 Cells, Gopika Ashokan

USF Tampa Graduate Theses and Dissertations

Background: Traumatic Brain Injury (TBI) is a major contributor to death and disability due to motorvehicle accidents, sports, physical abuse, and battlefield injuries. The primary insult to the brain leads to inflammation, vascular dysfunction, and oxidative stress in the brain as well as in the eye. This leads to loss of Retinal Ganglion Cells (RGCs) and downregulation of Brain derived Neurotopic Factor (BDNF). BDNF is a neurotrophic factor that binds to Tropomyosin Receptor Kinase B (TrkB) receptor to promote cell growth, survival, and differentiation. Current treatment strategies do not promote neuronal regeneration. Therefore, novel treatments are needed to restore vision …


Formulation Of Encapsulated Nanoparticles Of Leek Extract As Antimicrobial And Anticancer Agent, Rawan Hassan Mohamed Elghanam Feb 2023

Formulation Of Encapsulated Nanoparticles Of Leek Extract As Antimicrobial And Anticancer Agent, Rawan Hassan Mohamed Elghanam

Theses and Dissertations

Leek extract (LEK) has broad therapeutic activity. However, plant extract use has many drawbacks, which could be resolved using nanocarriers. The purpose of this research work was to prepare chitosan nanoparticles (CS NPs) encapsulating LEK and investigate their antioxidant, antimicrobial, and anticancer activity. Gas chromatography-mass spectroscopy was used to determine the LEK components. The CS-LEK NPs were produced by tripolyphosphate (TPP) crosslinking with chitosan (CS) the ionic gelation methodology. The particle size was 331 nm, zeta potential (ZP) was 28.9 mv, polydispersity index (PDI) was 0.4, encapsulation efficiency (EE) was 65.6%, and loading capacity (LC) was 28.8 % of the …


Synthesis, Characterization, And Application Of Chitosan Nanoparticles For In Vitro Studies On Hela Cancer Cells, Rejeena Jha Jan 2023

Synthesis, Characterization, And Application Of Chitosan Nanoparticles For In Vitro Studies On Hela Cancer Cells, Rejeena Jha

Graduate Theses/Dissertations

Chitosan is a fibrous substance that is derived from chitin, a natural substance in the shells of crustaceans. It possesses all the necessary qualities for being used as carrier for the transport of drugs and genes into tumor, such as biodegradability, biocompatibility, hydrophilicity, and non-toxicity and cationic in nature. Ionic gelation method was used to synthesize chitosan (CS) nanoparticles (NPs). Ionic gelation is a very benign process chemically that requires mixing a CS aqueous solution with a sodium tripolyphosphate (TPP) aqueous solution at room temperature. In addition, a surfactant polyethylene oxide (PEO) alone and a diblock copolymer of PEO and …


Effect Of Decorating Super Paramagnetic Iron Oxide Nanoparticles With Silver Nanoparticles On Their Magneto-Photo Thermal Heating Efficiency, Anthony Joseph Afful Jan 2023

Effect Of Decorating Super Paramagnetic Iron Oxide Nanoparticles With Silver Nanoparticles On Their Magneto-Photo Thermal Heating Efficiency, Anthony Joseph Afful

All Graduate Theses, Dissertations, and Other Capstone Projects

Cancer treatment is rather dangerous to the body, often involving many secondary effects, including nausea, hair loss, and weight fluctuations. The search for non-invasive, highly efficient, and targetable treatments ameliorates these issues. Super paramagnetic iron oxide nanoparticles (SPIONS) have been used for other medical purposes such as magnetic resonance imaging contrast agent and is being extensively studied as a potential candidate for many cancer therapeutic and diagnostic approaches due to its biocompatibility and superior magnetic properties. When subjected to an external alternating magnetic field SPIONS generate heat mainly due to the friction of the SPIONS against the fluid it is …


Nanoparticles For Biomedical Applications, Joseph Kim May 2022

Nanoparticles For Biomedical Applications, Joseph Kim

Dissertations and Theses (Open Access)

This thesis presents development and evaluation of the potential of three new nanoparticles for biomedical applications. With the rapid growth of the field of nanoscience, researchers have explored developing nanoparticles for various biomedical applications, including imaging, therapy, and drug delivery. This thesis demonstrates the development of two C­60 fullerene based nanoparticles and one boron based nanoparticle to answer key questions related to their biological potential.

In the first part of the thesis, we describe synthesis and characterization of a pure boron nanoparticle containing asolectin phospholipid-based liposome construct prepared using a water-in-oil emulsion method, as a novel alternative agent for …


Biomedical Applications Of Lanthanide Nanomaterials, For Imaging, Sensing And Therapy, Qize Zhang, Stephen O'Brien, Jan Grimm Jan 2022

Biomedical Applications Of Lanthanide Nanomaterials, For Imaging, Sensing And Therapy, Qize Zhang, Stephen O'Brien, Jan Grimm

Publications and Research

The application of nanomaterials made of rare earth elements within biomedical sciences continues to make significant progress. The rare earth elements, also called the lanthanides, play an essential role in modern life through materials and electronics. As we learn more about their utility, function, and underlying physics, we can contemplate extending their applications to biomedicine. This particularly applies to diagnosis and radiation therapy due to their relatively unique features, such as an ultra-wide Stokes shift in the luminescence, variable magnetism and potentially tunable properties, due to the library of lanthanides available and their multivalent oxidation state chemistry. The ability to …


Characterization Of Nanoparticles Using Inductively-Coupled Plasma Mass Spectrometry, Jabez D. Campbell Jan 2022

Characterization Of Nanoparticles Using Inductively-Coupled Plasma Mass Spectrometry, Jabez D. Campbell

Graduate Theses/Dissertations

Nanomaterials are a relatively new class of materials that have many applications which span a wide host of fields from medical products to consumer products. The possible compositions and forms of nanomaterials are just as varied as the applications. Therefore, a versatile characterization method is needed for researchers and regulators alike to ensure nanomaterials are properly used. Single Particle Inductively Coupled Plasma Mass Spectrometry (SP-ICP-MS) is a functional method that could fill the characterization need in the nanomaterial research field. Using data from both SP-ICP-MS tests and data from literature established characterization methods, the viability of making SP-ICP-MS the standard …


Multifunctional Programmable Self-Assembled Nanoparticles In Nanomedicine, Yoshie Sakamaki Dec 2021

Multifunctional Programmable Self-Assembled Nanoparticles In Nanomedicine, Yoshie Sakamaki

Graduate Theses and Dissertations

Developing methodologies to control the architecture of nanoparticles (NPs) at the atomic level prevents their inhomogeneity and leads to a variety of expected functions. Rationally designed nanoparticles can either be programmed or crystallized structures into pre-determined structures achieving tunable particle pore size and physiochemistry. In this dissertation, two broad classes of multifunctional nanoparticles are developed, metal-organic frameworks and DNA-NP aggregates.

Metal-organic frameworks are a novel class of highly porous crystalline materials built from organic linkers and metal cluster-based secondary building units. However, applications in bioremediation have not been developed very well especially in applications regarding drug delivery systems (DDS). The …


Molecular Dynamics Simulations Of Self-Assemblies In Nature And Nanotechnology, Phu Khanh Tang Sep 2021

Molecular Dynamics Simulations Of Self-Assemblies In Nature And Nanotechnology, Phu Khanh Tang

Dissertations, Theses, and Capstone Projects

Nature usually divides complex systems into smaller building blocks specializing in a few tasks since one entity cannot achieve everything. Therefore, self-assembly is a robust tool exploited by Nature to build hierarchical systems that accomplish unique functions. The cell membrane distinguishes itself as an example of Nature’s self-assembly, defining and protecting the cell. By mimicking Nature’s designs using synthetically designed self-assemblies, researchers with advanced nanotechnological comprehension can manipulate these synthetic self-assemblies to improve many aspects of modern medicine and materials science. Understanding the competing underlying molecular interactions in self-assembly is always of interest to the academic scientific community and industry. …


The Impact Of Nanopulse Treatment On The Tumor Microenvironment In Breast Cancer: Overturning The Treg Immunosuppressive Dominance, Anthony Nanajian Jul 2021

The Impact Of Nanopulse Treatment On The Tumor Microenvironment In Breast Cancer: Overturning The Treg Immunosuppressive Dominance, Anthony Nanajian

Biomedical Sciences Theses & Dissertations

Nanopulse treatment (NPT) is a high-power electric engineering modality that has been shown to be an effective local tumor treatment approach in multiple cancer models. Our previous studies on the orthotopic 4T1-luc breast cancer model demonstrated that NPT ablated local tumors. The treatment consequently conferred protection against a second live tumor challenge and minimized spontaneous metastasis. This study aims to understand how NPT mounts a potent immune response in a predominantly immunosuppressive tumor.

NPT changed the local and systemic dynamics of immunosuppressive cells by significantly reducing the numbers of regulatory T cells (Tregs), myeloid-derived suppressor cells (MDSCs), and tumor-associated macrophages …


Zein And Lignin-Based Nanoparticles As Delivery Systems: Pesticide Release And Nanoparticle Health Impact On Soybean Plants, Fallon Polette Salinas Gonzalez Jan 2021

Zein And Lignin-Based Nanoparticles As Delivery Systems: Pesticide Release And Nanoparticle Health Impact On Soybean Plants, Fallon Polette Salinas Gonzalez

LSU Doctoral Dissertations

This research examined the effect of biodegradable, polymeric, lignin-based nanoparticles (LNPs, 113.8±3.4, negatively charged) and zein nanoparticles (ZNP, 141.6±3.9, positively charged) on soybean plant health. The LNPs were synthesized from lignin, covalently linked to poly(lactic-co-glycolic) acid by emulsion evaporation. ZNPs were synthesized by nanoprecipitation. Soybeans grown hydroponically were treated with three concentrations (0.02, 0.2, and 2 mg/ml) of NPs at 28 days after germination. The effect of ZNPs and LNPs on plant health was determined through analysis of root and stem length, chlorophyll concentration, dry biomass of roots and stem, as well as carbon, nitrogen, and micronutrient absorption after 1, …


Inventions Of Scientists, Engineers And Specialists From Different Countries In The Area Of Nanotechnologies. Part Vi, Leonid A. Ivanov, Li D. Xu, Konstantin E. Razumeev, Zhanna V. Pisarenko, Aleksey V. Demenev Jan 2021

Inventions Of Scientists, Engineers And Specialists From Different Countries In The Area Of Nanotechnologies. Part Vi, Leonid A. Ivanov, Li D. Xu, Konstantin E. Razumeev, Zhanna V. Pisarenko, Aleksey V. Demenev

Information Technology & Decision Sciences Faculty Publications

Introduction. Advanced technologies impress people's imagination demonstrating the latest achievements (materials, methods, systems, technologies, devices etc.) that dramatically change the world. This, first of all, concerns nanotechnological inventions designed by scientists, engineers and specialists from different countries. Main part. The article provides an abstract overview of inventions of scientists, engineers and specialists from different countries: Russia, USA, China, Kazakhstan, Sweden. The results of the creative activity of scientists, engineers and specialists, including inventions in the field of nanotechnology and nanomaterials allow, when introduced to industry, achieving a significant effect in construction, housing and communal services, and related sectors of the …


Development Of Light Actuated Chemical Delivery Platform On A 2-D Array Of Micropore Structure, Hojjat Rostami Azmand, Hojjat Rostami Azmand Jan 2021

Development Of Light Actuated Chemical Delivery Platform On A 2-D Array Of Micropore Structure, Hojjat Rostami Azmand, Hojjat Rostami Azmand

Dissertations and Theses

Localized chemical delivery plays an essential role in the fundamental information transfers within biological systems. Thus, the ability to mimic the natural chemical signal modulation would provide significant contributions to understand the functional signaling pathway of biological cells and develop new prosthetic devices for neurological disorders. In this paper, we demonstrate a light-controlled hydrogel platform that can be used for localized chemical delivery in a high spatial resolution. By utilizing the photothermal behavior of graphene-hydrogel composites confined within micron-sized fluidic channels, patterned light illumination creates the parallel and independent actuation of chemical release in a group of fluidic ports. The …


Nebulizer-Based Systems To Improve Pharmaceutical Aerosol Delivery To The Lungs, Benjamin M. Spence Jan 2021

Nebulizer-Based Systems To Improve Pharmaceutical Aerosol Delivery To The Lungs, Benjamin M. Spence

Theses and Dissertations

Combining vibrating mesh nebulizers with additional new technologies leads to substantial improvements in pharmaceutical aerosol delivery to the lungs across therapeutic administration methods. In this dissertation, streamlined components, aerosol administration synchronization, and/or Excipient Enhanced Growth (EEG) technologies were utilized to develop and test several novel devices and aerosol delivery systems. The first focus of this work was to improve the poor delivery efficiency, e.g., 3.6% of nominal dose (Dugernier et al. 2017), of aerosolized medication administration to adult human subjects concurrent with high flow nasal cannula (HFNC) therapy, a form of continuous-flow non-invasive ventilation (NIV). The developed Low-Volume Mixer-Heater (LVMH) …


Methods To Investigate Hyperthermia Induced By Tumor Treating Fields, Ruchi Singh Aug 2020

Methods To Investigate Hyperthermia Induced By Tumor Treating Fields, Ruchi Singh

Dissertations and Theses (Open Access)

Tumor Treating Fields (TTFields) are an antineoplastic treatment delivered via application of alternating electric fields using insulated transducer arrays placed directly on the skin in the region surrounding the tumor. TTF’s is a non-invasive application of low-intensity (1-3 V/cm), intermediate-frequency (100-500 kHz) alternating electric fields. The predominant mechanism by which TTFields are thought to kill tumor cells is the disruption of mitosis through the depolymerization of microtubules and interruption of the spindle structure leading to mitotic catastrophe and the formation of non-viable daughter cells. Tumor Treating fields do not stimulate nerves and muscle because of their high frequency, and do …


Hyaluronic Acid Coated Targeted Lipid Micellar Nanoparticle As A Delivery Vehicle For Lapatinib And Ketoconazole In Egfr Mutated Lung Cancer, Nadia Tasnim Ahmed Jun 2020

Hyaluronic Acid Coated Targeted Lipid Micellar Nanoparticle As A Delivery Vehicle For Lapatinib And Ketoconazole In Egfr Mutated Lung Cancer, Nadia Tasnim Ahmed

USF Tampa Graduate Theses and Dissertations

Background: According to the American Cancer Society, lung cancer was accountable for over 142,000 deaths in the USA in 2019. Common mutations related to lung cancer mainly occur in TP53, EGFR, and KRAS genes. Lapatinib is a small molecule tyrosine kinase inhibitor which acts reversibly on both epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2). Overexpression of EGFR leads to increased production and signaling of proteins that cause upregulation of cellular proliferation, cholesterol synthesis and resistance to apoptosis. Ketoconazole is an imidazole antifungal agent which works principally by inhibiting the enzyme cytochrome P450 14α-demethylase (CYP51A1) …


Hybrid Electro-Plasmonic Stimulation Of Primary Neurons, Ratka Damnjanovic Apr 2020

Hybrid Electro-Plasmonic Stimulation Of Primary Neurons, Ratka Damnjanovic

USF Tampa Graduate Theses and Dissertations

Biomedical prosthetics utilizing electrical stimulation have limited, effective spatial resolution due to spread of electrical currents to surrounding tissue, causing nonselective stimulation. So, precise spatial resolution is not possible for traditional neural prosthetic devices, such as cochlear implants. More recently, alternative methods utilize optical stimulation, mainly infrared, sometimes paired with nanotechnology for stimulating action potentials, which has its own drawbacks, as it may heat surrounding tissue. Recently, we employed plasmonic stimulation methods utilizing gold nanoparticle-coated nanoelectrodes to convert visible light pulses into localized surface plasmon resonance transduction for stimulation of electrically excitable cells, which had limited success. Here, we report …


Cardiorespiratory Fitness, Balance And Walking Improvements In An Adolescent With Cerebral Palsy (Gmfcs Ii) And Autism After Motor-Assisted Elliptical Training, Guilherme Manna Cesar, Thad W. Buster, Judith M. Burnfield Jan 2020

Cardiorespiratory Fitness, Balance And Walking Improvements In An Adolescent With Cerebral Palsy (Gmfcs Ii) And Autism After Motor-Assisted Elliptical Training, Guilherme Manna Cesar, Thad W. Buster, Judith M. Burnfield

Department of Mechanical and Materials Engineering: Faculty Publications

Purpose: To quantify the impact of motor-assisted elliptical (ICARE) training on cardiorespiratory fitness, balance and walking function of an adolescent with walking limitations due to cerebral palsy.

Materials and methods: A thirteen-year-old boy with hemiplegic cerebral palsy (Gross Motor Function Classification System II) and autism participated. Peak oxygen consumption (peak VO2, primary outcome measure), oxygen cost of walking, Pediatric Balance Scale (PBS), modified Timed Up and Go (mTUG), 2-Minute Walk Test (2MWT), and gait characteristics (speed, cadence, step length, single support time) were assessed prior to and after completion of 24 sessions of moderate- to vigorous- intensity ICARE …


Interfacial Current Distribution Between Helium Plasma Jet And Water Solution, Sui Wang, Dingxin Liu, Zifeng Wang, Yifan Liu, Qiaosong Li, Xiaohua Wang, Michael G. Kong, Mingzhe Rong Jan 2020

Interfacial Current Distribution Between Helium Plasma Jet And Water Solution, Sui Wang, Dingxin Liu, Zifeng Wang, Yifan Liu, Qiaosong Li, Xiaohua Wang, Michael G. Kong, Mingzhe Rong

Bioelectrics Publications

The plasma-liquid interaction holds great importance for a number of emerging applications such as plasma biomedicine, yet a main fundamental question remains about the nature of the physiochemical processes occurring at the plasma-liquid interface. In this paper, the interfacial current distribution between helium plasma jet and water solution was measured for the first time by means of the splitting electrode method, which was borrowed from the field of arc plasma. For a plasma plume in continuous mode, it was found that the mean absolute current distribution at the plasma-liquid interface typically had an annular shape. This shape could be affected …


Formulation And Validation Of Nanoparticle Controlled Delivery For Chemotherapeutic Drug Products, Shani L. Levit Jan 2020

Formulation And Validation Of Nanoparticle Controlled Delivery For Chemotherapeutic Drug Products, Shani L. Levit

Theses and Dissertations

Taxol, a formulation of paclitaxel (PTX), is one of the most widely used anticancer drugs, particularly for treating recurring ovarian carcinomas following surgery. Clinically, PTX is used in combination with other drugs such as lapatinib (LAP) to increase treatment efficacy. Delivering drug combinations with nanoparticles has the potential to improve chemotherapy outcomes. In this study, we use Flash NanoPrecipitation, a rapid, scalable process to encapsulate weakly hydrophobic drugs (logP in vitro. Encapsulating either PTX or LAP into nanoparticles increases drug potency. When PTX and LAP are co-loaded in the same nanoparticle, they have a synergistic effect that is greater than …


Quantitative Study Of The Antimicrobial Effects Of Silver On The Motility Of Escherichia Coli, Benjamin Russell Dec 2019

Quantitative Study Of The Antimicrobial Effects Of Silver On The Motility Of Escherichia Coli, Benjamin Russell

Graduate Theses and Dissertations

In recent decades, the number of antibiotic-resistant bacterial infections has grown to become a serious global threat. This rise can be attributed to the widespread misuse of antibiotics and the lack of newly developed drugs to fight resistant organisms. Novel bactericidal substances have, therefore, garnered significant research interest. Silver, due to its powerful antimicrobial effects, is one such substance. Silver is typically most effective in cationic form; however, advancements in nanotechnology have paved the way for the controlled fabrication of nano-silver. Silver nanoparticles have been shown to have increased antibacterial potency for a variety of reasons, including the release of …


Chemical Structure Of Fe–Ni Nanoparticles For Efficient Oxygen Evolution Reaction Electrocatalysis, Prashant Acharya, Zachary J. Nelson, Mourad Benamara, Ryan H. Manso, Sergio I. Perez Bakovic, Mojtaba Abolhassani, Sungsik Lee, Benjamin Reinhart, Jingyi Chen, Lauren F. Greenlee Oct 2019

Chemical Structure Of Fe–Ni Nanoparticles For Efficient Oxygen Evolution Reaction Electrocatalysis, Prashant Acharya, Zachary J. Nelson, Mourad Benamara, Ryan H. Manso, Sergio I. Perez Bakovic, Mojtaba Abolhassani, Sungsik Lee, Benjamin Reinhart, Jingyi Chen, Lauren F. Greenlee

Chemical Engineering Faculty Publications and Presentations

Bimetallic iron–nickel-based nanocatalysts are perhaps the most active for the oxygen evolution reaction (OER) in alkaline electrolytes. Recent developments in literature have suggested that the ratio of iron and nickel in Fe–Ni thin films plays an essential role in the performance and stability of the catalysts. In this work, the metallic ratio of iron to nickel was tested in alloy bimetallic nanoparticles. Similar to thin films, nanoparticles with iron–nickel atomic compositions where the atomic iron percentage is ≤50% outperformed nanoparticles with iron–nickel ratios of >50%. Nanoparticles of Fe20Ni80, Fe50Ni50, and Fe80Ni20 compositions were evaluated and demonstrated to have overpotentials of …


Roles Of Surfactant And Binary Polymers On Dissolution Enhancement Of Bcs Ii Drugs From Nanocomposites And Amorphous Solid Dispersions, Md Mahbubur Rahman Aug 2019

Roles Of Surfactant And Binary Polymers On Dissolution Enhancement Of Bcs Ii Drugs From Nanocomposites And Amorphous Solid Dispersions, Md Mahbubur Rahman

Dissertations

Drug nanocomposites and amorphous solid dispersions (ASDs) are two major formulation platforms used for the bioavailability enhancement of BCS Class II drugs. The major drawback of nanocomposites is their inability to attain high drug supersaturation during in vitro (<50% relative supersaturation) and in vivo dissolution. On the other hand, formulating an amorphous solid dispersion (ASD) with high drug loading (>20%) that releases drug rapidly, while generating and maintaining high supersaturation over at least three hours is challenging. The goal of this thesis is to develop a fundamental understanding of the impact of anionic surfactants–polymers on in vitro drug release from nanocomposites and ASDs, while addressing the above challenges. To achieve this goal, the following objectives are set: (1) compare griseofulvin …


Iron-Containing Nanoparticles For The Treatment Of Chrionic Biofilm Infections In Cystic Fibrosis, Leisha M. A. Martin Apr 2019

Iron-Containing Nanoparticles For The Treatment Of Chrionic Biofilm Infections In Cystic Fibrosis, Leisha M. A. Martin

Nanoscience and Microsystems ETDs

Cystic fibrosis (CF) is the most common genetic disease resulting in the morbidity and mortality of Caucasian children and adults worldwide. Due to a genetic mutation resulting in malfunction of the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) protein, CF patients produce highly viscous mucus in their respiratory tract. This leads to impairment of the mucociliary clearance of inhaled microbes. In addition to reduced microbial clearance, anoxic environmental conditions in the lungs promote biofilm-mode growth of the pathogenic bacterial species Pseudomonas aeruginosa. Chronic infections of P. aeruginosa begin in early childhood and typically persist until respiratory failure and death result. The …


Incorporation Of Egfr And Ron Receptors Into Nanodiscs, Cristina Flores-Cadengo Apr 2019

Incorporation Of Egfr And Ron Receptors Into Nanodiscs, Cristina Flores-Cadengo

Biomedical Engineering ETDs

Understanding the structure-function relationship of membrane receptors is essential to comprehend the crosstalk between key signaling pathways. Aberrant trans-activation between receptors can lead to tumorigenesis. Two of these receptors known to be involved in cancer development are receptor tyrosine kinases (RTKs), RON (Recepteur d'Origine Nantais) and EGFR (Epidermal Growth Factor Receptor). There has been evidence of heterodimerization and crosstalk between these two receptors based on co-immunoprecipitation, however the structural requirements behind these interactions remain unknown. Structural studies could provide insights into these RTKs’ modes of dimerization and structure-function relationship. However, structural studies of full-length membrane proteins are often difficult due …


Å-Indentation For Non-Destructive Elastic Moduli Measurements Of Supported Ultra-Hard Ultra-Thin Films And Nanostructures, Filippo Cellini, Yang Gao, Elisa Riedo Mar 2019

Å-Indentation For Non-Destructive Elastic Moduli Measurements Of Supported Ultra-Hard Ultra-Thin Films And Nanostructures, Filippo Cellini, Yang Gao, Elisa Riedo

Publications and Research

During conventional nanoindentation measurements, the indentation depths are usually larger than 1–10 nm, which hinders the ability to study ultra-thin films (<10 >nm) and supported atomically thin two-dimensional (2D) materials. Here, we discuss the development of modulated Å-indentation to achieve sub-Å indentations depths during force-indentation measurements while also imaging materials with nanoscale resolution. Modulated nanoindentation (MoNI) was originally invented to measure the radial elasticity of multi-walled nanotubes. w, by using extremely small amplitude oscillations (<<1 Å) at high frequency, and stiff cantilevers, we show how modulated nano/Å-indentation (MoNI/ÅI) enables non-destructive measurements of the contact stiffness and indentation modulus of ultra-thin ultra-stiff films, including CVD diamond films (~1000 GPa stiffness), as well as the transverse modulus of 2D materials. Our analysis demonstrates that in presence of a standard laboratory noise floor, the signal to noise ratio of MoNI/ÅI implemented with a commercial atomic force microscope (AFM) is such that a dynamic range of 80 dB –– achievable with commercial Lock-in amplifiers –– is sufficient to observe superior indentation curves, having indentation depths as small as 0.3 Å, resolution in indentation <0.05 Å, and in normal load <0.5 nN. Being implemented on a standard AFM, this method has the potential for a broad applicability.


Development Of 3d Printed And 3d Metal-Based Micro/Nanofabricated, And Nano-Functionalized, Microelectrode Array (Mea) Biosensors For Flexible, Conformable, And In Vitro Applications, Charles Didier Jan 2019

Development Of 3d Printed And 3d Metal-Based Micro/Nanofabricated, And Nano-Functionalized, Microelectrode Array (Mea) Biosensors For Flexible, Conformable, And In Vitro Applications, Charles Didier

Electronic Theses and Dissertations

Emerging fields such as "Organs on a Chip", disease modeling in vitro, stem cell manufacturing and wearable bioelectronics are demanding rapid development of 3D Microelectrode Arrays (MEAs) for electrical interfacing with biological constructs. The work reported in this thesis focuses on two developmental tracks: "Dynamic 3D MEAs" and metal microfabrication for 3D MEAs. In the first part of the thesis, we explore the capabilities and limitations of 3D printed microserpentines (µserpentines) and utilize these structures to develop dynamic 3D microelectrodes. Analytical modeling of µserpentines flexibility followed by integration into a flexible Kapton® package and PDMS insulation are demonstrated. These 3D …


Fabrication And Characterization Of Nanofiber Nylon-6-Mwcnt As An Electrochemical Sensor For Sodium Ions Concentration Detection In Sweat, Kelsey Mills Jan 2019

Fabrication And Characterization Of Nanofiber Nylon-6-Mwcnt As An Electrochemical Sensor For Sodium Ions Concentration Detection In Sweat, Kelsey Mills

Williams Honors College, Honors Research Projects

Fabrication and characterization nylon-6-MWCNT nanofiber as an electrochemical sensor to detect sodium ion concentrations specifically in sweat. Using contact angle to determine surface morphology and chronoamperometry testing to identify ideal sensor conditions, tests optimized parameters like weight percent of nylon or other polymers, carbon nanotube (CNT) isomer, and solution concentration to determine reproducibility of functional sensors. Utilizing the electric qualities of carbon nanotubes partnered with the sodium ion selectivity of calixarene treatment and polymers unique properties like flexibility and scalability create open an arena for optimizing sodium ion sensors for further development for functional prototypes. Morphology tests showed that the …


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 develop …


Migration Resistance Of Esophageal Stents: The Role Of Stent Design, Hozhabr Mozafari, Pengfei Dong, Shijia Zhao, Yonghua Bi, Xinwei Han, Linxia Gu Jun 2018

Migration Resistance Of Esophageal Stents: The Role Of Stent Design, Hozhabr Mozafari, Pengfei Dong, Shijia Zhao, Yonghua Bi, Xinwei Han, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

Objective: Stenting is one of the major treatments for malignant esophageal cancer. However, stent migration compromises clinical outcomes. A flared end design of the stent diminishes its migration. The goal of this work is to quantitatively characterize stent migration to develop new strategies for better clinical outcomes.

Methods: An esophageal stent with flared ends and a straight counterpart were virtually deployed in an esophagus with asymmetric stricture using the finite element method. The resulted esophagus shape, wall stress, and migration resistance force of the stent were quantified and compared.

Results: The lumen gain for both the flared stent and the …