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Full-Text Articles in Biomedical Engineering and Bioengineering

Influence Of Naoh Concentration On Transfer Process Of Graphene, Francisco Saldana, Chengyu Wen, George Patrick Watson Sep 2019

Influence Of Naoh Concentration On Transfer Process Of Graphene, Francisco Saldana, Chengyu Wen, George Patrick Watson

Protocols and Reports

The process of transferring a monolayer of graphene using two different concentrations of sodium hydroxide (NaOH) solution unto a silicon dioxide (SiO2) coated Si chip using electrochemistry was performed. The transfer process is crucial for the delamination of a continuous graphene monolayer film from copper foil. After examining and inspecting the integrity of the graphene monolayer, it was observed that the lower concentration to NaOH led to slower rate of hydrogen bubble generation; this condition was found to be less destructive and yielded a graphene film with fewer visible tears.


Investigation Of The Electrode Polarization Effect For Biosensor Applications, Anil Koklu Aug 2019

Investigation Of The Electrode Polarization Effect For Biosensor Applications, Anil Koklu

Mechanical Engineering Research Theses and Dissertations

My research focuses on electrokinetic transport. Particularly, in this dissertation, we focus on fabrication and testing of micro electrodes with nanostructured surfaces to minimize the electrode polarization (EP) effects for biosensor applications. In the first study, electrochemical deposition of gold nanoparticles on to planar gold electrodes was used to generate rough surfaces. Dendritic nanostructures that reduced EP up to two orders of magnitude was obtained by optimizing the deposition conditions. These structures also enhanced dielectrophoresis (DEP) response of our bio-chips, making them usable in physiological buffers. In further studies we discovered a universal scaling of EP in the frequency domain ...


Investigation Of Fundamental Principles Of Rigid Body Impact Mechanics, Khalid Alluhydan Jul 2019

Investigation Of Fundamental Principles Of Rigid Body Impact Mechanics, Khalid Alluhydan

Mechanical Engineering Research Theses and Dissertations

In impact mechanics, the collision between two or more bodies is a common, yet a very challenging problem. Producing analytical solutions that can predict the post-collision motion of the colliding bodies require consistent modeling of the dynamics of the colliding bodies. This dissertation presents a new method for solving the two and multibody impact problems that can be used to predict the post-collision motion of the colliding bodies. Also, we solve the rigid body collision problem of planar kinematic chains with multiple contacts with external surfaces.

In the first part of this dissertation, we study planar collisions of Balls and ...


Compositional Optimization Of Amyloid-Graphene Oxide Nanohybrids For Biomaterials, Claire L. Drewery Jun 2019

Compositional Optimization Of Amyloid-Graphene Oxide Nanohybrids For Biomaterials, Claire L. Drewery

Materials Engineering

Amyloid nanofibrils are natural materials capable of self-assembling into precise structures with tunable functionalities, while exhibiting excellent mechanical properties. In combination with highly conductive graphene oxide (GO), the 1-D amyloid nanofibrils and 2-D nanosheets of GO can produce a robust and bio-functional nanohybrid, hypothesized to exhibit multi-domain functional properties useful for enzyme sensing, water purification, drug delivery, and tissue scaffolding applications. Here, we examine the properties of an amyloid-graphene oxide nanohybrid film made with amyloids derived from hen egg white lysozymes in an attempt to explore the diverse toolbox of amyloid derivatives and establish ideal fabrication methods and formulations of ...


Fabrication And Characterization Of Collagen-Polypyrrole Constructs Using Direct-Ink Write Additive Manufacturing, Rooshan Arshad May 2019

Fabrication And Characterization Of Collagen-Polypyrrole Constructs Using Direct-Ink Write Additive Manufacturing, Rooshan Arshad

Electronic Thesis and Dissertation Repository

Current efforts in the tissue engineering field are being directed towards the creation of platforms which will facilitate in instructing cells towards biologically relevant outcomes such as stem cell differentiation and disease pathophysiology. Traditional fabrication methods serve as a limiting factor for the production of such platforms as they lack feature and geometric complexity. Additive Manufacturing (AM) offers advantage over said methods by affording designers creative freedom and great control over printed constructs. Such constructs can then be used to create appropriate models for study- ing a plethora of tissues and structures. An AM methodology for Direct-Ink Write (DIW) printing ...


Generation Of Silver Nanoparticle Pharmacokinetic Profiles In A Lung Model, Rachel Galaska Apr 2019

Generation Of Silver Nanoparticle Pharmacokinetic Profiles In A Lung Model, Rachel Galaska

Honors Theses

Nanomaterial technologies are becoming increasingly prevalent in consumer and industrial applications, including drug delivery, energy harvesting, environmental applications, and medicine due to their unique physiochemical properties. As nanomaterial use increases, so too does human exposure. This has made it progressively more important to understand the toxicological effects of nanomaterials and their interactions with the human body. Silver nanoparticles (AgNPs) are one of the most commonly used nanomaterials due to their antibacterial properties. As inhalation is one of the most common exposure routes, understanding the toxicity of these AgNPs on lung tissue was studied. Using A549 cells for a lung tissue ...


Effect Of Activated Carbon On The Performance Of A Solar Thermal Adsorptive Refrigerator (Star) Using Activated Carbon-Ethanol, Joshua Romo Apr 2019

Effect Of Activated Carbon On The Performance Of A Solar Thermal Adsorptive Refrigerator (Star) Using Activated Carbon-Ethanol, Joshua Romo

Honors Theses

The Solar Thermal Adsorptive Refrigerator (STAR) project at the University of Dayton seeks to bridge sustainability and the need for reliable refrigeration in developing communities. Cost-effective construction, operation, and maintenance as well as the use of a sustainable adsorption pair, activated carbon-ethanol, give STAR great potential in the realm of humanitarian engineering. This project explores the effect of using two activated carbon brands, 8x16 and CocoPlus, on the cyclic performance of the STAR system. Although both brands have similar specifications given by the manufacturer, one (8x16) inhibited successful performance while the other (CocoPlus) enabled it. This project highlights both the ...


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 ...


Reactive Ion Etching Selectivity Of Si/Sio2: Comparing Of Two fluorocarbon Gases Chf3 And Cf4, Meiyue Zhang, Pat Watson Mar 2019

Reactive Ion Etching Selectivity Of Si/Sio2: Comparing Of Two fluorocarbon Gases Chf3 And Cf4, Meiyue Zhang, Pat Watson

Protocols and Reports

Two reactive ion etching (RIE) processes were studied to show the relative etch selectivity between SiO2 and Si using two fluorocarbon gases, CF4 and CHF3. Results show that CHF3 gives better selectivity (16:1) over CF4 (1.2 :1). On the other hand, the etch rate of SiO2 of CF4 is approximately 52.8 nm/min, faster than CHF3 (32.4 nm/min).


Simulations Of Hydrogel-Coated Neural Microelectrodes To Assess Biocompatibility Improvement Using Strain As A Metric For Micromotion, Sarah A. Bentil, Rebecca B. Dupaix Feb 2019

Simulations Of Hydrogel-Coated Neural Microelectrodes To Assess Biocompatibility Improvement Using Strain As A Metric For Micromotion, Sarah A. Bentil, Rebecca B. Dupaix

Sarah A. Bentil

This study investigates the benefit of coating silicon-substrate microelectrode arrays with hydrogel material for improved biocompatibility. Varying coating thicknesses and hydrogel material descriptions were considered to determine the impact on reducing strain in the surrounding brain tissue caused by relative micromotion of the electrode. Finite element simulations were used to explore biocompatibility by focusing on the longitudinal micromotion of an implanted single electrode shank. The finite element model for the brain and electrode, both with and without the hydrogel coating, remained constant. Three constitutive models were considered to describe the brain and/or hydrogel material: linear elastic, hyperviscoelastic, and fractional ...


Ice-Binding Protein From Shewanella Frigidimarinas Inhibits Ice Crystal Growth In Highly Alkaline Solutions, Elizabeth Delesky, Shane D. Frazier, Jaqueline D. Wallat, Kendra L. Bannister, Chelsea Marie Heveran, Wil V. Srubar Iii Feb 2019

Ice-Binding Protein From Shewanella Frigidimarinas Inhibits Ice Crystal Growth In Highly Alkaline Solutions, Elizabeth Delesky, Shane D. Frazier, Jaqueline D. Wallat, Kendra L. Bannister, Chelsea Marie Heveran, Wil V. Srubar Iii

University Libraries Open Access Fund Supported Publications

The ability of a natural ice-binding protein from Shewanella frigidimarina (SfIBP) to inhibit ice crystal growth in highly alkaline solutions with increasing pH and ionic strength was investigated in this work. The purity of isolated SfIBP was first confirmed via sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and size-exclusion chromatography with an ultraviolet detector (SEC-UV). Protein stability was evaluated in the alkaline solutions using circular dichroism spectroscopy, SEC-UV, and SDS-PAGE. SfIBP ice recrystallization inhibition (IRI) activity, a measure of ice crystal growth inhibition, was assessed using a modified splat assay. Statistical analysis of results substantiated that, despite partial denaturation and ...


Degradation And Remodeling Of Epitaxially Grown Collagen Fibrils, Juan Wang, Anuraag Boddupalli, Joseph Koelbl, Dong Hyun Nam, Xin Ge, Kaitlin M. Bratlie, Ian C. Schneider Feb 2019

Degradation And Remodeling Of Epitaxially Grown Collagen Fibrils, Juan Wang, Anuraag Boddupalli, Joseph Koelbl, Dong Hyun Nam, Xin Ge, Kaitlin M. Bratlie, Ian C. Schneider

Materials Science and Engineering Publications

Introduction: The extracellular matrix (ECM) in the tumor microenvironment contains high densities of collagen that are highly aligned, resulting in directional migration called contact guidance that facilitates efficient migration out of the tumor. Cancer cells can remodel the ECM through traction force controlled by myosin contractility or proteolytic activity controlled by matrix metalloproteinase (MMP) activity, leading to either enhanced or diminished contact guidance.

Methods: Recently, we have leveraged the ability of mica to epitaxially grow aligned collagen fibrils in order to assess contact guidance. In this article, we probe the mechanisms of remodeling of aligned collagen fibrils on mica by ...


Use Of Flexible Sensor To Characterize Biomechanics Of Canine Skin, Austin R. J. Downey, Jin Yan, Eric M. Zellner, Karl H. Kraus, Iris V. Rivero, Simon Laflamme Jan 2019

Use Of Flexible Sensor To Characterize Biomechanics Of Canine Skin, Austin R. J. Downey, Jin Yan, Eric M. Zellner, Karl H. Kraus, Iris V. Rivero, Simon Laflamme

Civil, Construction and Environmental Engineering Publications

Background: Suture materials and techniques are frequently evaluated in ex vivo studies by comparing tensile strengths. However, the direct measurement techniques to obtain the tensile forces in canine skin are not available, and, therefore, the conditions suture lines undergo is unknown. A soft elastomeric capacitor is used to monitor deformation in the skin over time by sensing strain. This sensor was applied to a sample of canine skin to evaluate its capacity to sense strain in the sample while loaded in a dynamic material testing machine. The measured strain of the sensor was compared with the strain measured by the ...


Coatings On Mammalian Cells: Interfacing Cells With Their Environment, Kara A. Davis, Pei-Jung Wu, Calvin F. Cahall, Cong Li, Anuhya Gottipati, Brad J. Berron Jan 2019

Coatings On Mammalian Cells: Interfacing Cells With Their Environment, Kara A. Davis, Pei-Jung Wu, Calvin F. Cahall, Cong Li, Anuhya Gottipati, Brad J. Berron

Chemical and Materials Engineering Faculty Publications

The research community is intent on harnessing increasingly complex biological building blocks. At present, cells represent a highly functional component for integration into higher order systems. In this review, we discuss the current application space for cellular coating technologies and emphasize the relationship between the target application and coating design. We also discuss how the cell and the coating interact in common analytical techniques, and where caution must be exercised in the interpretation of results. Finally, we look ahead at emerging application areas that are ideal for innovation in cellular coatings. In all, cellular coatings leverage the machinery unique to ...


Computational Protein Design For Peptide-Directed Bioconjugation, Joseph Gabriel Plaks Jan 2019

Computational Protein Design For Peptide-Directed Bioconjugation, Joseph Gabriel Plaks

Chemical & Biological Engineering Graduate Theses & Dissertations

Proteins enable living organisms to perform many of their critical functions, having been applied over evolutionary time to solve problems of overwhelming diversity and complexity. Protein engineering seeks to deploy these versatile molecules in addressing problems of human concern and would benefit from innovations that improve protein utilization in unnatural environments as well as from increased predictive capability in protein design.

Bioconjugation facilitates the use of proteins in unnatural environments by permitting the attachment of molecules, such as polymers, that can modulate protein stability, solubility, and activity and by mediating protein immobilization. We initially explored this propensity of bioconjugation by ...


Development Of Novel Crispr-Based Methods For Transcriptional Control Over Bacterial Gene Expression, Katia Tarasava Jan 2019

Development Of Novel Crispr-Based Methods For Transcriptional Control Over Bacterial Gene Expression, Katia Tarasava

Materials Science & Engineering Graduate Theses & Dissertations

One of the challenges of the 21st century is creating a sustainable economy that is able to serve the needs of a growing population with the decreasing supply of natural resources. In addition to alternative energy sources, renewable economy concerns production of materials and chemicals. The chemical and polymer industries rely heavily on petroleum for manufacturing consumer goods. Many of these chemicals can be produced from renewable resources using microorganisms. However, the amounts produced are often not enough to make the process commercially viable. By rewiring cellular metabolism and regulation, it is possible to redirect metabolic flux to increase the ...


Effects Of Micro-Features On Cell Detachment From Poly(N-Isopropylacrylamide) Coated Polydimethylsiloxane Membranes, Luke Webel Jan 2019

Effects Of Micro-Features On Cell Detachment From Poly(N-Isopropylacrylamide) Coated Polydimethylsiloxane Membranes, Luke Webel

Williams Honors College, Honors Research Projects

The tested hypothesis was that features on polydimethylsiloxane (PDMS) surfaces coated with a poly(N-isopropylacrylamide)/aminopropyltriethoxysilane or pNIPAAM/APTES thin film would accelerate cell detachment than the film coated on a unfeatured surface. This project tested samples with features generated by molds, wrinkling, and sandpaper roughened substrates. Surface feature generation methods were limited to mechanical means, and characterized by microscopy and strain rates. 50/50 mixtures of 1.5 wt.% pNIPAAM/ APTES were used to coat thin films (30-40 nm) on PDMS membranes by spin-coating, and the coated membranes were thermally annealed to chemically graft pNIPAAm/APTES on the membrane ...


Nanoscale Stiffness Cues Influence Valvular Interstitial Cell Activation To Myofibroblasts, Michaela Wenning Jan 2019

Nanoscale Stiffness Cues Influence Valvular Interstitial Cell Activation To Myofibroblasts, Michaela Wenning

Undergraduate Honors Theses

Surgery is currently the primary treatment option for aortic valve stenosis (AVS) patients, many of whom are ineligible for surgery and are left untreated. AVS is progression is known to differ between males and females, and an understanding of sex-specific mechanisms of disease progression is imperative in developing accurate treatment options for men and women. The development of a nonsurgical therapy for AVS patients requires a deeper understanding of the molecular and cellular mechanisms of AVS progression. Currently, the role of calcium phosphate nanoparticles detected in the aortic valve during early stages of AVS in influencing disease progression and valvular ...


The Transcriptional Response Of Phanerochaete Chrysosporium And Trametes Versicolor To Growth On Stems Of Helianthus Argophyllus (Silverleaf Sunflower), Nadh Hamoud Alsubaie Jan 2019

The Transcriptional Response Of Phanerochaete Chrysosporium And Trametes Versicolor To Growth On Stems Of Helianthus Argophyllus (Silverleaf Sunflower), Nadh Hamoud Alsubaie

Masters Theses

Traditional physicochemical and physicomechanical pretreatment technologies have improved the deconstruction of lignocellulose, but often require high energy inputs and added chemical reagents. Recent studies have demonstrated the use of white-rot fungi as alternative biological pretreatment agents that can mitigate these concerns. Although, white-rot fungi have been shown to grow on a variety of non-woody substrates, they have not been explored with respect to sunflower, which has the potential to provide raw materials for both biodiesel and bioethanol. In the present study, Silverleaf sunflower stems (Helianthus argophyllus) were used as substrates for the white-rot fungi Phanerochaete chrysosporium and Trametes versicolor, and ...


How Crosslinking Mechanisms Of Methacrylated Gellan Gum Hydrogels Alter Macrophage Phenotype, Zhuqing Li, Kaitlin M. Bratlie Dec 2018

How Crosslinking Mechanisms Of Methacrylated Gellan Gum Hydrogels Alter Macrophage Phenotype, Zhuqing Li, Kaitlin M. Bratlie

Materials Science and Engineering Publications

In tissue engineering scaffolds, macrophages play a critical role in determining the host response to implanted biomaterials. Macrophage phenotype is dynamic throughout the host response, and a balance of phenotypes is essential for timely progression from injury to proper wound healing. Therefore, it is important to predict how materials will modulate the response of macrophages. In this study, we investigated the effect of methacrylated gellan gum hydrogels on macrophage phenotype and proliferation with the ultimate goal of improving rational design of biomedical implants. Naïve, along with classically and alternatively activated RAW 264.7 macrophages were seeded on methacrylated gellan gum ...


The Subject Librarian Newsletter, Engineering And Computer Science, Fall 2017, Buenaventura "Ven" Basco Oct 2018

The Subject Librarian Newsletter, Engineering And Computer Science, Fall 2017, Buenaventura "Ven" Basco

Buenaventura "Ven" Basco

No abstract provided.


Pneumatospinning Of Collagen Microfibers From Benign Solvents, Seth Polk, Nardos Sori, Nick Thayer, Yas Maghdouri-White, Anna A. Bulysheva, Michael P. Francis Oct 2018

Pneumatospinning Of Collagen Microfibers From Benign Solvents, Seth Polk, Nardos Sori, Nick Thayer, Yas Maghdouri-White, Anna A. Bulysheva, Michael P. Francis

Medical Diagnostics & Translational Sciences Faculty Publications

Introduction. Current collagen fiber manufacturing methods for biomedical applications, such as electrospinning and extrusion, have had limited success in clinical translation, partially due to scalability, cost, and complexity challenges. Here we explore an alternative, simplified and scalable collagen fiber formation method, termed 'pneumatospinning,' to generate submicron collagen fibers from benign solvents. Methods and results. Clinical grade type I atelocollagen from calf corium was electrospun or pneumatospun as sheets of aligned and isotropic fibrous scaffolds. Following crosslinking with genipin, the collagen scaffolds were stable in media for over a month. Pneumatospun collagen samples were characterized using Fourier-transform infrared spectroscopy, circular dichroism ...


Electrospun Collagen Fibers For Tissue Regeneration Applications, Ying Li Sep 2018

Electrospun Collagen Fibers For Tissue Regeneration Applications, Ying Li

Electronic Thesis and Dissertation Repository

Tissue engineering aims to regenerate damaged and deceased tissue by combining cells with scaffold made from an appropriate biomaterial and providing a conducive environment to guide cell growth and the formation or regeneration of new tissue or organ. While collagen, an important material of the extracellular matrix (ECM), is a natural choice as a scaffold biomaterial, the conducive environment can only be created by having the ability to control the geometry, organization, structural and mechanical properties of the scaffold. Moreover, degradability and degradation rate control of the scaffold has to be taken into consideration too. In this work, we aim ...


Treatment Of Neurodegenerative Disorders Through The Blood-Brain Barrier Using Nanocarriers, Nitya Poovaiah, Zahra Davoudi, Haisheng Peng, Benjamin Schlichtmann, Surya K. Mallapragada, Balaji Narasimhan, Qun Wang Aug 2018

Treatment Of Neurodegenerative Disorders Through The Blood-Brain Barrier Using Nanocarriers, Nitya Poovaiah, Zahra Davoudi, Haisheng Peng, Benjamin Schlichtmann, Surya K. Mallapragada, Balaji Narasimhan, Qun Wang

Chemical and Biological Engineering Publications

Neurodegenerative diseases refer to disorders of the central nervous system (CNS) that are caused by neuronal degradations, dysfunctions, or death. Alzheimer’s disease, Parkinson’s disease, and Huntington’s disease (APHD) are regarded as the three major neurodegenerative diseases. There is a vast body of literature on the causes and treatments of these neurodegenerative diseases. However, the main obstacle in developing an effective treatment strategy is the permeability of the treatment components to the blood-brain barrier (BBB). Several strategies have been developed to improve this obstruction. For example, nanomaterials facilitate drug delivery to the BBB due to their size. They ...


Developing Strategies To Toughen Bio-Inspired Adhesives, Narelli P. Narciso, Samuel Lee Huntington, Jonathan J. Wilker Aug 2018

Developing Strategies To Toughen Bio-Inspired Adhesives, Narelli P. Narciso, Samuel Lee Huntington, Jonathan J. Wilker

The Summer Undergraduate Research Fellowship (SURF) Symposium

Mussels and other marine creatures adhere very well in underwater environments, having the ability to withstand the force of the sea. These animals have inspired synthetic biomimetic adhesives for wet systems, presenting potential for biomedical applications. However, most current commercial adhesives tend to be brittle, not resisting repetitive movements. This study assesses toughening strategies to improve the mussel-inspired adhesives’ ductility while maintaining its strength. The strategies included altering the polymer’s chemical structure by changing the percentage of polyethylene glycol (PEG) in the molecule and by adding fillers, such as calcium carbonate, silica and nacre - a calcium carbonate compound found ...


Tissue-Engineered Vascular Grafts: Recellularisation And Surface Functionalisation With Hybrid Magnetic Nanomedicine Developed With Theranostic Potential, Tatiane Eufrásio Da Silva Jul 2018

Tissue-Engineered Vascular Grafts: Recellularisation And Surface Functionalisation With Hybrid Magnetic Nanomedicine Developed With Theranostic Potential, Tatiane Eufrásio Da Silva

PhD theses

Cardiovascular Disease is the number one cause of death in the world, with a mortality rate, globally of 35.1% representing 17.6 million lives lost annually. The majority of these deaths are related to vascular diseases, such as atherosclerotic plaques, which can obstruct blood flow perfusion of organs and tissue causing serious injuries or even death. In the heart, in order to prevent heart failure, blood flow to the tissue must be restored as quickly as possible, ideally via minimally invasive interventions such as stenting or other types of angioplasty as the gold standard. However, this is not always ...


Chemically Modified Gellan Gum Hydrogels With Tunable Properties For Use As Tissue Engineering Scaffolds, Zihao Xu, Zhuqing Li, Shan Jiang, Kaitlin M. Bratlie Jun 2018

Chemically Modified Gellan Gum Hydrogels With Tunable Properties For Use As Tissue Engineering Scaffolds, Zihao Xu, Zhuqing Li, Shan Jiang, Kaitlin M. Bratlie

Chemical and Biological Engineering Publications

Gellan gum is a naturally occurring polymer that can cross-link in the presence of divalent cations to form biocompatible hydrogels. However, physically cross-linked gellan gum hydrogels lose their stability under physiological conditions, thus restricting the applications of these hydrogels in vivo. To improve the mechanical strength of the gels, we incorporated methacrylate into the gellan gum and chemically cross-linked the hydrogel through three polymerization methods: step growth through thiol–ene photoclick chemistry, chain-growth via photopolymerization, and mixed model in which both mechanisms were employed. Methacrylation was confirmed and quantified by proton nuclear magnetic resonance (1H NMR) and Fourier transform infrared ...


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 ...


Structure And Property Of Polymers And Biopolymers From Molecular Dynamic Simulations, Xiaoquan Sun May 2018

Structure And Property Of Polymers And Biopolymers From Molecular Dynamic Simulations, Xiaoquan Sun

Theses and Dissertations

Natural and synthetic polymers and biopolymers have been studied for a variety of applications in food emulsion, biopharmaceutical purification, tissue engineering, and biosensor. The structure and property of polymers and biopolymers are critically important to determine their functions. Molecular dynamics (MD) simulations have a unique advantage to explore the structure and property of polymers and biopolymers from the molecular level. In the dissertation, MD simulations were conducted to study the mechanisms of various biological and chemical processes controlled by polymers and biopolymers based on real-world experimental results.

Seven heptapeptides have been screened from a peptide library in our earlier study ...


Simulations Of Hydrogel-Coated Neural Microelectrodes To Assess Biocompatibility Improvement Using Strain As A Metric For Micromotion, Sarah A. Bentil, Rebecca B. Dupaix Apr 2018

Simulations Of Hydrogel-Coated Neural Microelectrodes To Assess Biocompatibility Improvement Using Strain As A Metric For Micromotion, Sarah A. Bentil, Rebecca B. Dupaix

Mechanical Engineering Publications

This study investigates the benefit of coating silicon-substrate microelectrode arrays with hydrogel material for improved biocompatibility. Varying coating thicknesses and hydrogel material descriptions were considered to determine the impact on reducing strain in the surrounding brain tissue caused by relative micromotion of the electrode. Finite element simulations were used to explore biocompatibility by focusing on the longitudinal micromotion of an implanted single electrode shank. The finite element model for the brain and electrode, both with and without the hydrogel coating, remained constant. Three constitutive models were considered to describe the brain and/or hydrogel material: linear elastic, hyperviscoelastic, and fractional ...