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Cleveland State University

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Articles 31 - 60 of 193

Full-Text Articles in Biomedical Engineering and Bioengineering

A 3d Cancer Cell Migration Assay On A 384-Pillar Plate With Sidewalls, Nicholas Lesh, Alexander Roth, Stephen Hong, Oju Jeon, Eben Alsberg Jan 2018

A 3d Cancer Cell Migration Assay On A 384-Pillar Plate With Sidewalls, Nicholas Lesh, Alexander Roth, Stephen Hong, Oju Jeon, Eben Alsberg

Undergraduate Research Posters 2018

Hepatocellular carcinoma (HCC) is an aggressive liver cancer where prognosis is heavily tied to metastasis progression. Researchers look to determine the triggers for metastasis to control its spread. The goal of this project is to determine these triggers by quantifying Hep3B cell migration on a high-throughput platform. We infected Hep3B cells with lentiviruses containing mCherry to produce stable fluorescent cells. Next, we determined the stability of growth factors in oxidized, methacrylated alginate (OMA) hydrogel by binding growth factors with methacrylated heparin sulfate (MHS) before encapsulating in OMA, printing onto the 384-pillar plate with sidewalls, and quantifying growth factor release via …


Boundary Effects On The Locomotion Of Active Janus Particles, Marola W. Issa, Nicky R. Baumgartner Jan 2018

Boundary Effects On The Locomotion Of Active Janus Particles, Marola W. Issa, Nicky R. Baumgartner

Undergraduate Research Posters 2018

Self-propelled or “active” micrometer scale particles are capable of supplying local mechanical work, necessary for microscale cargo delivery and useful in other applications within bioimaging and sensing. Research in the last decade has focused on developing, measuring, and manipulating the locomotion mechanisms of active particles in simple environments. However, many applications will be in complex environments with nearby boundaries or variations in physiochemical cues. This poster reports the directed motion of platinum coated polystyrene particles at infinite dilution in the presence of H2O2, which acts as a fuel to drive motion. A transport mechanism called “diffusiophoresis” drives motion of the …


Treatment Of Non-Epithelial Vaginal Cells From Lysyl Oxidase Like One Knockout Mice (Loxl 1) With Nanoparticles (Nps), Priya Patel Jan 2018

Treatment Of Non-Epithelial Vaginal Cells From Lysyl Oxidase Like One Knockout Mice (Loxl 1) With Nanoparticles (Nps), Priya Patel

Undergraduate Research Posters 2018

Female pelvic floor dysfunction includes pelvic organ prolapse (POP) due to multiple vaginal births causing elastin strength to be reduced. Several normal functions are compromised including bladder control, fecal continence, and painful urination and many other symptoms. Currently no effective treatment is known and women seek surgical mesh implants to correct these issues which are not entirely safe nor effective. The condition of POP affects women across the world and effective treatment is sought. Varying proteins including lysyl oxidase (LOX), tissue inhibitors of metalloproteinases, and matrix metalloproteinases are involved in elastin homeostasis. In this experiment, non-epithelial vaginal cells (NEVCs) retrieved …


The Role Of Synthesis Solvent In Particle Size Of Metal Organic Frameworks, Jonathan Krisak Jan 2018

The Role Of Synthesis Solvent In Particle Size Of Metal Organic Frameworks, Jonathan Krisak

Undergraduate Research Posters 2018

Metal organic frameworks are a class of nanoporous materials with pore sizes ranging from 0.5 to 3 nm and high surface areas (500-6000 m2/g). These materials have potential applications in industrial catalysis, separation and purification, bio-mimetics, drug delivery, semiconductors, sensors and other electronics. The aim of this study is to understand the role of solvent in control of the particle size of the final MOF product. CuBTC MOF has been used as a model MOF in this study to understand this effect. Altering the dielectric constant of solvents is a potential method of controlling the particle size. The data obtained …


The Effect Of Cognitive Limb Embodiment On Vascular Physiological Response, Hala Elsir Mustafa Osman Jan 2018

The Effect Of Cognitive Limb Embodiment On Vascular Physiological Response, Hala Elsir Mustafa Osman

ETD Archive

The rubber hand illusion (RHI) is a visual-tactile perceptual illusion commonly used to study body ownership. In this paradigm, a rubber hand is positioned in front of a participant, and the person’s real hand is hidden from sight behind a barrier. When the real hand and the rubber hand are stroked synchronously, individuals perceive the rubber hand as if it were their own; it becomes “embodied.” This illusory experience of body ownership is associated with multimodal integration of touch and vision. From these visual-tactile-cognitive mechanisms, we establish that our hands belong to us when what we see matches what we …


Characterizing The Effects Of High-Intensity Exercise On Balance And Gait Under Dual-Task Conditions In Parkinson’S Disease, El Iva Baron Jan 2018

Characterizing The Effects Of High-Intensity Exercise On Balance And Gait Under Dual-Task Conditions In Parkinson’S Disease, El Iva Baron

ETD Archive

Parkinson’s disease (PD) is a neurodegenerative disorder, characterized by four cardinal motor symptoms including bradykinesia, tremor, rigidity, and postural instability, and non-motor symptoms including cognitive impairment. Daily activities, such as walking and maintaining balance, are impacted due to impairments in motor function, and are further exacerbated with the addition of cognitive loading, or dual-tasking (DT). High-intensity exercise has demonstrated centrally-mediated improvements of PD symptoms, with additional positive effects on overall health. The goal of this project was to identify changes in dynamic balance recovery and gait function under conditions with and without increased cognitive load after a high-intensity exercise intervention …


Neuromuscular Reflex Control For Prostheses And Exoskeletons, Sandra K. Hnat Jan 2018

Neuromuscular Reflex Control For Prostheses And Exoskeletons, Sandra K. Hnat

ETD Archive

Recent powered lower-limb prosthetic and orthotic (P/O) devices aim to restore legged mobility for persons with an amputation or spinal cord injury. Though various control strategies have been proposed for these devices, specifically finite-state impedance controllers, natural gait mechanics are not usually achieved. The goal of this project was to invent a biologically-inspired controller for powered P/O devices. We hypothesize that a more muscle-like actuation system, including spinal reflexes and vestibular feedback, can achieve able-bodied walking and also respond to outside perturbations. The outputs of the Virtual Muscle Reflex (VMR) controller are joint torque commands, sent to the electric motors …


Feasibility Of Using An Equilibrium Point Strategy To Control Reaching Movements Of Paralyzed Arms With Functional Electrical Stimulation, Matthew Huffman Jan 2018

Feasibility Of Using An Equilibrium Point Strategy To Control Reaching Movements Of Paralyzed Arms With Functional Electrical Stimulation, Matthew Huffman

ETD Archive

Functional electrical stimulation (FES) is a technology capable of improving the quality of life for those with the loss of limb movement related to spinal cord injuries. Individuals with high-level tetraplegia, in particular, have lost all movement capabilities below the neck. FES has shown promise in bypassing spinal cord damage by sending electrical impulses directly to a nerve or muscle to trigger a desired function. Despite advancements in FES, full-arm reaching motions have not been achieved, leaving patients unable to perform fundamental tasks such as eating and grooming. To overcome the inability in current FES models to achieve multi-joint coordination, …


A Synthesis Platform For Temperature Responsive Star Polymers, Schmitt J. Richard Jr. Jan 2018

A Synthesis Platform For Temperature Responsive Star Polymers, Schmitt J. Richard Jr.

ETD Archive

Star polymers are a class of branched polymers comprised of several polymer chains extending from a central point. Star polymers have applications in biopharmaceuticals where they have been proposed to be suitable drug delivery vehicles. Star polymers have traditionally been synthesized through chemical synthesis with added functionality provided by grafting on the arms. This complex synthesis can be simplified by using a biosynthetic approach which enables precise control of molecular weight and composition. This approach is demonstrated using star polymers with arms composed of a temperature responsive protein-based polymer termed elastin-like polypeptide (ELP). Star polymers are characterized based on the …


Stabilization Of Hypoxia Inducible Factor By Cobalt Chloride Can Alter Renal Transepithelial, Subhra Sankar Nag Jan 2018

Stabilization Of Hypoxia Inducible Factor By Cobalt Chloride Can Alter Renal Transepithelial, Subhra Sankar Nag

ETD Archive

Kidney cyst expansion, stagnant fluid accumulation, and insufficient vascular supply can result in localized chronic ischemia-hypoxia in kidney cysts, as well as in normal renal epithelia adjacent to a cyst. We hypothesize that in normal epithelia near a cyst, the stabilization of Hypoxia Inducible Factor 1a (HIF1a), a major regulator of cellular response to hypoxia, can cause altered paracellular and transcellular transport, transforming a normal absorptive phenotype to a secretory and paracellularly leaky phenotype, leading to cyst expansion. Using 100 µmol/L cobalt chloride (CoCl2), HIF1a was stabilized in cellular nucleus of a mouse cortical collecting duct cell line (mCCD 1296 …


Predictive Simulations Of Gait And Their Application In Prosthesis Design, Anne D. Koelewijin Jan 2018

Predictive Simulations Of Gait And Their Application In Prosthesis Design, Anne D. Koelewijin

ETD Archive

Predictive simulations predict human gait by solving a trajectory optimization problem by minimizing energy expenditure. These simulations could predict the effect of a prosthesis on gait before its use. This dissertation has four aims, to show the application of predictive simulations in prosthesis design and to improve the quality of predictive simulations. Aim 1 was to explain joint moment asymmetry in the knee and hip in gait of persons with a transtibial amputation (TTA gait). Predictive simulations showed that an asymmetric gait required less effort. However, a small effort increase yielded a gait with increased joint moment symmetry and reduced …


High-Throughput Metabolism-Induced Toxicity Assays On A 384-Pillar Plate, Sooyeion Kang Jan 2018

High-Throughput Metabolism-Induced Toxicity Assays On A 384-Pillar Plate, Sooyeion Kang

ETD Archive

The U.S Environmental Protection Agency (EPA) launched the Transform Tox Testing Challenge in 2016 with the goal of developing practical methods that can be integrated into conventional high-throughput screening (HTS) assays to better predict the toxicity of parent compounds and their metabolites in vivo. In response to this need and to retrofit existing HTS assays for assessing metabolism-induced toxicity of compounds, we have developed a 384-pillar plate that is complementary to traditional 384-well plates and ideally suited for culturing human cells in three dimensions (3D) at a microscale. Briefly, human embryonic kidney (HEK) 293 cells in a mixture of alginate …


Multi-Phase Waste Gasification – Reaction Engineering For Sustainable Living Environments, Kristen M. Reyes, Mason J. Lang Jan 2018

Multi-Phase Waste Gasification – Reaction Engineering For Sustainable Living Environments, Kristen M. Reyes, Mason J. Lang

Undergraduate Research Posters 2018

Gasification converts carbon-based (organic) materials into gaseous products typically referred to as synthetic gas. This technology is an alternative for reducing carbon footprint of energy generation as well as for waste management. This research examines Catalytic Gasification as a route to Sustainability while converting spaceflight and municipal waste into high-value products. As polyethylene (PE) makes up one of the largest portions of both municipal and space waste, this project centered its attention on the gasification of mid-density PE. We used a slurry containing middensity PE, water, and solid catalysts (ruthenium on alumina, Ru/Al2O3) in a 1:1 PE/Ru ratio. The gasification …


Methodology Development For The Implementation Ofmicrofluidic Mixers, Tahir Butt, Gautam Mahajan Jan 2018

Methodology Development For The Implementation Ofmicrofluidic Mixers, Tahir Butt, Gautam Mahajan

Undergraduate Research Posters 2018

Microfluidic platforms have been widely regarded as defining technologies for the development of chemical and biological synthesis and analysis systems, due to benefits associated with reduced reactant consumption, increases by orders of magnitude of the surface-to-volume ratios, and greatly enhanced control over reactions variables such as temperature and pressure. However, one of the bottlenecks for their wide application is the difficulty in achieving mixing, given the typical laminar flows in these systems. In this work we implement experimentally, various strategies using geometrical features to control the fluid motion and induce stirring flows. The mixers are fabricated using soft-lithography in PDMS …


Characterizing Complexes Of Dna And Elastin-Like Polypeptides, Bryce Noe Jan 2018

Characterizing Complexes Of Dna And Elastin-Like Polypeptides, Bryce Noe

Undergraduate Research Posters 2018

Elastin-like polypeptides (ELPs) are a class of environmental responsive materials. When prepared with a protein motif that selectively binds to nucleic acids, a nucleic acid-ELP complex can be formed, conferring the responsive properties of ELP onto the nucleic acid. One possible use for such a complex is in DNA origami, where nanoscaled assemblies of DNA can be transformed into nanomachines by using the ELP as an actuator. Other possible uses include the isolation and extraction of a selected strands of genetic material, or the delivery of genetic material to a cell. Using a bacterial expression system, our lab has prepared …


Surface Functionalization Of Pure-Chirality Carbon Nanotubes By Covalent And Noncovalent Chemistry, Fjorela Xhyliu, Niyousha Mohammad Shafie Jan 2018

Surface Functionalization Of Pure-Chirality Carbon Nanotubes By Covalent And Noncovalent Chemistry, Fjorela Xhyliu, Niyousha Mohammad Shafie

Undergraduate Research Posters 2018

Single-wall carbon nanotubes (SWCNTs) are one-dimensional cylindrical nanostructures with distinct electronic and optical properties. With all its atoms on the surface, SWCNTs have been widely explored for chemical modification through noncovalent and covalent chemistry, which can provide promising applications in bioimaging and sensing. Here we investigated surface functionalization of purechirality SWCNTs with various glycopolymers, surfactants, and RPMI cell culture media with and without fetal bovine serum (FBS). Raman, vis-NIR absorption, and vis-NIR fluorescence spectra of SWCNTs in various solvent environments were monitored over time. While nanotube aggregation was not observed for incubation in FBS containing RPMI for 8 hours, interactions …


Idiosyncratic Drug-Induced Liver Injury (Idili): Potential Mechanisms And Predictive Assays, Alexander D. Roth, Moo-Yeal Lee Jan 2017

Idiosyncratic Drug-Induced Liver Injury (Idili): Potential Mechanisms And Predictive Assays, Alexander D. Roth, Moo-Yeal Lee

Chemical & Biomedical Engineering Faculty Publications

Idiosyncratic drug-induced liver injury (IDILI) is a significant source of drug recall and acute liver failure (ALF) in the United States. While current drug development processes emphasize general toxicity and drug metabolizing enzyme- (DME-) mediated toxicity, it has been challenging to develop comprehensive models for assessing complete idiosyncratic potential. In this review, we describe the enzymes and proteins that contain polymorphisms believed to contribute to IDILI, including ones that affect phase I and phase II metabolism, antioxidant enzymes, drug transporters, inflammation, and human leukocyte antigen (HLA). We then describe the various assays that have been developed to detect individual reactions …


C-Jun N-Terminal Kinase Inhibitory Nanotherapeutics For Regenerative Elastic Matrix Repair In Abdominal Aortic Aneurysms, Andrew T. Camardo Jan 2017

C-Jun N-Terminal Kinase Inhibitory Nanotherapeutics For Regenerative Elastic Matrix Repair In Abdominal Aortic Aneurysms, Andrew T. Camardo

ETD Archive

Abdominal aortic aneurysms (AAA) are localized expansions of the aorta wall that continue to grow until they reach a critical size and fatally rupture. This growth is driven by the chronic disruption, degradation, and subsequent loss of aortal wall elastic fibers by matrix metalloproteinases (MMPs) secreted by inflammatory cells recruited to the aorta wall following an injury stimulus, and the inherent inability of vascular smooth muscle cells (SMCs) to naturally repair or regenerate elastic fibers. This leads to a net loss of elastic matrix and the continuing weakening of the aortal wall until eventual rupture. Current treatments seek to reinforce …


P1: Using Modified Dean Flow Designs To Increase Mixing Performance, Joshua Clark Jan 2017

P1: Using Modified Dean Flow Designs To Increase Mixing Performance, Joshua Clark

Undergraduate Research Posters 2017

We are using numerical solutions for the Navier-Stokes equations and the concentration - diffusion equation to model fluid flow and reactant distribution in serpentine type channels for micromixers/microreactors development. These mixers exploit centripetal forces on the fluid to induce cross-sectional fluid mixing, aka Dean flows. Various modifications are used to increase the mixing character of these crosssectional flows. We found that the performance of these mixers exceeds that of unmodified channels and we currently assess their performance relative to other state of the art methodologies used to induce mixing on the microscale.


P2: Implementation Of Groove Based Designs For Engineering Fluid Flow In Micromixers, Tahir Butt Jan 2017

P2: Implementation Of Groove Based Designs For Engineering Fluid Flow In Micromixers, Tahir Butt

Undergraduate Research Posters 2017

Mixing on microscale is important for the development of miniaturized chemical reactors that use small quantities of reactants and allow better control over the reaction conditions and products. Nevertheless, achieving rapid mixing in this type of micro-reactors is challenging due to the lack of turbulence and slow diffusion on the microscale. In this work we implement micromixers designs based on surface groove/ridge patterns targeted at inducing cross-sectional flows that both extend the interface between the different reactants, as well as induce chaotic advection. We discuss the fabrication of these structures using soft-lithography in PDMS employing a mold and their optical …


Going Green: Experimental Adaptation Of Scenedesmus Dimorphus To Marine Conditions, Mohammed Khalil Jan 2017

Going Green: Experimental Adaptation Of Scenedesmus Dimorphus To Marine Conditions, Mohammed Khalil

Undergraduate Research Posters 2017

Algae has gained some interest as the need for alternative fuels becomes more pressing. Reliance on fossil fuels is causing our environment and economy harm, and is not sustainable moving forward. Lipid rich algae strains can be used in the production of biofuels, and provide an alternative fuel source. One challenge facing the prospect of algae as a fuel source is that lipid rich algae grows exclusively in freshwater. Considering the scarcity and cost to use freshwater for algae growth, interest has grown in the possibility of adapting lipid rich, freshwater algae to a seawater environment. Seawater can have up …


Development And Verification Of A Mechanical Loading Device For Microfluidics, Stefan Habean, Erin Tesny Jan 2017

Development And Verification Of A Mechanical Loading Device For Microfluidics, Stefan Habean, Erin Tesny

Undergraduate Research Posters 2017

Establishing the role that mechanics play in nerve cell (e.g. neurons) function requires experimental testing. Microfluidic based experiments are commonly used to study neuron growth and function, and studies have found mechanics to play an important role in neuron health. External loads can be applied to a microfluidic device using a motor, which presumably influences the mechanical environment of the cells. While a motor can easily apply known displacements, a “load cell” is necessary to measure corresponding forces. In an existing prototype microfluidic loading device, a load cell was integrated and verified. The manufacturer's calibration of the load cell was …


Design And Control Of A Powered Rowing Machine With Programmable Impedance, Jose Humberto De La Casas Zolezzi Jan 2017

Design And Control Of A Powered Rowing Machine With Programmable Impedance, Jose Humberto De La Casas Zolezzi

ETD Archive

Due to the rise of obesity, diabetes and cardiovascular disease, research in human performance and physical activity has received increased attention. Rowing machines are used for performance improvements through concentric exercises, however a combination of concentric and eccentric actions is known to improve the effectiveness of training. In this work, a conventional rowing machine was modified to include an electric motor and a robust impedance control system, enabling programmable impedance with concentric and eccentric capabilities. Eccentric exercises are known to contribute significantly to the efficacy of training and to diminish the detrimental effects of humans operating in microgravity for long …


Cathepsin K Targeting Matrix Regenerative Nanoparticles For Small Abdominal Aortic Aneurysm Repair, Jonathan M. Fox Jan 2017

Cathepsin K Targeting Matrix Regenerative Nanoparticles For Small Abdominal Aortic Aneurysm Repair, Jonathan M. Fox

ETD Archive

Abdominal aortic aneurysms (AAAs) are characterized by the loss of elasticity in the aorta wall leading to a chronic increase in diameter and resulting in rupture. This is due to the lack of regeneration of elastic fibers and chronic proteolytic breakdown of elastic fibers within the aorta mediated by matrix metalloproteinases (MMPs), specifically MMP-2 and -9. Previous studies in our lab have shown cationic amphiphile-surface functionalized poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) loaded with doxycycline (DOX) to inhibit MMP activity and stimulate elastic matrix synthesis, effects we attributed to both low doses (< 10 mg/ml) of DOX released and independent effects of cationic amphiphile pendant groups on the NP surface. This promises application of these NPs to arrest or regress AAA growth since high oral DOX dosing inhibits new elastic matrix formation in the AAA wall and has undesirable side effects. In this study, we investigated feasibility of antibody-based active targeting of intravenously infused NPs to the AAA wall. Cathepsin K, a cysteine protease, is a biomarker for AAA and overexpressed in abdominal aortic aneurysm tissue making it an ideal target moiety. We have shown using a covalent conjugation method of modifying the surface of the NPs with a cathepsin K antibody resulted in a more robust antibody attachment which did not affect the DOX release profile. Cathepsin K expression was confirmed to be localized on the cell surface and utilizing cathepsin K Ab-conjugated NPs, we demonstrated an increased NP localization to the cathepsin K overexpressing cells in vitro and ex vivo. Importantly, the DOX-loaded NPs demonstrated pro-elastogenic and anti-proteolytic effects in aneurysmal smooth muscle cells supporting their use as regenerative therapies to arrest and regress AAA growth. Preliminary data has been collected indicating cathepsin K Ab-conjugated NP targeting to AAAs in elastase-injured rat models. The study outcomes support the feasibility of using cathepsin K Ab-conjugated NPs as a targeted therapy for elastic matrix regeneration in AAA tissue and will serve as a basis for already initiated follow up studies to assess NP biodistribution, in situ retention in the AAA wall, and safety as a function of time.


Methodological Considerations Of Electron Spin Resonance Spin Trapping Techniques For Measuring Reactive Oxygen Species Generated From Metal Oxide Nanomaterials, Min Sook Jeong, Kyeong-Nam Yu, Hyun Hoon Chung, Soo Jin Park, Ah Young Lee, Mi Ryoung Song, Myung-Haing Cho, Jun Sung Kim May 2016

Methodological Considerations Of Electron Spin Resonance Spin Trapping Techniques For Measuring Reactive Oxygen Species Generated From Metal Oxide Nanomaterials, Min Sook Jeong, Kyeong-Nam Yu, Hyun Hoon Chung, Soo Jin Park, Ah Young Lee, Mi Ryoung Song, Myung-Haing Cho, Jun Sung Kim

Chemical & Biomedical Engineering Faculty Publications

Qualitative and quantitative analyses of reactive oxygen species (ROS) generated on the surfaces of nanomaterials are important for understanding their toxicity and toxic mechanisms, which are in turn beneficial for manufacturing more biocompatible nanomaterials in many industrial fields. Electron spin resonance (ESR) is a useful tool for detecting ROS formation. However, using this technique without first considering the physicochemical properties of nanomaterials and proper conditions of the spin trapping agent (such as incubation time) may lead to misinterpretation of the resulting data. In this report, we suggest methodological considerations for ESR as pertains to magnetism, sample preparation and proper incubation …


Decitabine-Loaded Nanogel Treatment To Reverse Cancer Drug Resistance, Samantha A. Cramer Jan 2016

Decitabine-Loaded Nanogel Treatment To Reverse Cancer Drug Resistance, Samantha A. Cramer

ETD Archive

Cancers in which epigenetic changes, such as hypermethylation of DNA, lead to drug resistance cause the cancer to become unresponsive to existing chemotherapeutic treatments. The epigenetic drug – 5-aza-2’-deoxycytidine (decitabine, DAC) – is a potent hypomethylating agent, but its effect is transient due to its instability. Previous studies have shown that loading DAC into nanogel significantly enhances its antiproliferative effect (compared to DAC in solution) in drug-resistant breast cancer cells (MCF-7/ADR). Further, the previous studies demonstrated changes in the membrane lipid profile of resistant cells following treatment with DAC either as solution or in nanogels. The objective of the present …


Design And Production Of A Hydrogel Forming Polypeptide: Engaging High School Students In Protein Design, James K. Deyling Jan 2016

Design And Production Of A Hydrogel Forming Polypeptide: Engaging High School Students In Protein Design, James K. Deyling

ETD Archive

Bioinks are a class of hydrogel that have the potential to be the ink used in the creation of printed organs, connective tissue, and other important structures within the body. One class of material that may be a suitable bioink hydrogel is elastin-like polypeptides (ELPs), which are synthetic biopolymers inspired by the naturally existing connective tissue elastin. ELPs consist of a repeat pentapeptide sequence (GXGVP)n, where X is any of the 20 naturally existing amino acids other than proline. These biomolecules are capable of exhibiting environmental responsiveness when exposed to certain stimulus such as salt concentration, temperature, and pH, depending …


Time And Temperature Dependent Surface Tension Measurements Of Responsive Protein-Based Polymer Surfactant Solutions, Hakan Celik Jan 2015

Time And Temperature Dependent Surface Tension Measurements Of Responsive Protein-Based Polymer Surfactant Solutions, Hakan Celik

ETD Archive

A three-armed star elastin-like polypeptide (ELP-foldon) has thermoreversible character which exhibits phase separation above a transition temperature (Tt) in physiologic salt concentrations. At lower salt concentration, the ELP-foldon behaves like a thermoresponsive surfactant, exhibiting micelle formation above its Tt. The purpose of this study is characterize the surfactant behavior of the ELP-foldon at air-liquid interface by measuring the surface tension. The surface tension is measured as a function of time for different ELP concentrations from 10 nM to 50 ℗æM and over range of temperatures from 25 to 35 ℗¿ using the axisymmetric drop shape analysis (ADSA). The ADSA is …


Solute Partitioning In Elastin-Like Polypeptides: A Foundation For Drug Delivery Applications, Eric Helm Jan 2015

Solute Partitioning In Elastin-Like Polypeptides: A Foundation For Drug Delivery Applications, Eric Helm

ETD Archive

No abstract provided.


Characterization Of Highly Concentrated Elastin-Like Polypeptide Solutions: Rheometric Properties And Phase Separation Analysis, Kevin Michael Otto Jan 2015

Characterization Of Highly Concentrated Elastin-Like Polypeptide Solutions: Rheometric Properties And Phase Separation Analysis, Kevin Michael Otto

ETD Archive

Elastin-like polypeptides (ELPs) are environmentally responsive biopolymers. These protein based polymers are specific in that they exhibit phase separation in response to a number of stimuli. Some of these stimuli include temperature, light, and pH. There are a large number of factors to consider when designing ELP constructs that allow for control of the transitioning behavior, some of which include amino acid sequences, protein concentration, salt concentration, and the polymer chain length. Elastin-like polypeptides are soluble in water at low temperatures, however, upon an increase in temperature, the proteins become insoluble in water and phase separate. This point of temperature …