Engineering Commons^™

Methodology Of Citric Acid Based Functional Biomaterial Development And Application, Yi Leaf Zhang

Bioengineering Dissertations - Archive

Biomaterials play critical roles in modern strategies of biomedical applications, such as tissue engineering, and theranostic therapy. Attempts to design ideal biomaterials for each specific application have led to an enormous increase in the number of polymeric biomaterials. Different biomedical applications require specific functionality of biomaterials. Unfortunately, the limited versatility of currently available biodegradable polymers fails to meet the wide range of requirement for biomedical applications. Therefore, a methodology of functional biomaterials development would be beneficial to the biomaterial field. It has been proved that citric acid can be utilized as a key element in the development of novel biodegradable …

Phase Sensitive Spectral Domain Interferometry For Label Free Biomolecular Interaction Analysis And Biosensing Applications, Sajal Chirvi

Bioengineering Dissertations - Archive

Biomolecular interaction analysis (BIA) plays vital role in wide variety of fields, which include biomedical research, pharmaceutical industry, medical diagnostics, and biotechnology industry. Study and quantification of interactions between natural biomolecules (proteins, enzymes, DNA) and artificially synthesized molecules (drugs) is routinely done using various labeled and label-free BIA techniques. Labeled BIA (Chemiluminescence, Fluorescence, Radioactive) techniques suffer from steric hindrance of labels on interaction site, difficulty of attaching labels to molecules, higher cost and time of assay development. Label free techniques with real time detection capabilities have demonstrated advantages over traditional labeled techniques. The gold standard for label free BIA is …

Application Of Scanning Correlation Spectroscopy Techniques To Quantify Dna Double Strand Break Repair Kinetics In The Living Cell After Exposure To Γ-Rays And Radiomimetic Chemicals, Salim Abdisalaam

Bioengineering Dissertations - Archive

The kinetics of most proteins involved in DNA damage sensing, signaling and repair following ionizing radiation exposure cannot be quantified by current live cell fluorescence microscopy methods. This is because most of these proteins, with only few notable exceptions, do not attach in large numbers at DNA damage sites to form easily detectable foci in microscopy images. As a result a high fluorescence background from freely moving and immobile fluorescent proteins in the nucleus masks the aggregation of proteins at sparse DNA damage sites. Currently, the kinetics of these repair proteins are studied by laser-induced damage and Fluorescence Recovery After …

Development Of Sers Nanoprobes For Multiplexed And Multi-Modality Molecular Diagnosis Of Cancer, James Otieno Nyagilo

Bioengineering Dissertations - Archive

Importance of cancer diagnosis and staging through molecular biomarker detection is evident in the increasing number of molecular biomarkers being discovered that are associated with specific cancers types with their role in disease severity and progression being elucidated. Development of molecular imaging modalities capable of simultaneously detecting multiple molecular biomarkers will have a major impact on research, detection, diagnosis, treatment and monitoring of cancer. Combining molecular imaging with high resolution structural imaging can potentially deliver a cancer diagnostic imaging platform with superior resolution and sensitivity. Nanotechnology, specifically in the form of functionalized metal nanoparticles exhibit unique chemical and electromagnetic properties …

Micro-Device For Selective Isolation And Cytology Of Cancer Cells, Yuan Wan

Bioengineering Dissertations - Archive

Early detection and isolation of circulating tumor cells (CTCs) can enable early cancer diagnosis and more effective therapeutics. Aptamers have emerged as probe molecules that have binding affinities comparable to antibodies but specificities better than those of antibodies. Epidermal Growth Factor Receptor (EGFR) is the most frequently overexpressed receptor in all human malignancies. The expression levels of EGFR in cancer cells can be over 100 times higher than those in normal cells. It is an attractive target for cancer therapy and cancer cell isolation.This dissertation focuses on two different areas: developing strategies for anti-EGFR aptamer based cancer cell isolation, and …

Raman Spectroscopy And Diffuse Reflectance Spectroscopy For Diagnosis Of Human Cancer And Acanthosis Nigricans, Suneetha Devpura

Wayne State University Dissertations

Cancer and diabetes are common chronic diseases in today's world causing numerous deaths in adults as well as children. Most common types of cancers in adults include prostate, lung, breast, colorectal and head and neck squamous cell carcinoma, while among children; leukemia, and brain and central nervous system cancers are quite common. In each of these cases, early detection of the cancer or disease dramatically increases the chances of successful treatment. In recent years, there has been much interest in using Raman spectroscopy and diffuse reflectance spectroscopy as analytical optical spectroscopic methods for early diagnosis of diseases. Raman spectroscopy can …

Development Of Gelatin Microbubble Based Plga Scaffold For Application In Bone Tissue Engineering, Krishna M. Shah

Bioengineering Theses - Archive

The overall goal of the study was to develop a delivery system for a potential bone tissue engineering application focusing on fabrication of gelatin microbubble (MB) based PLGA scaffolds capable of recruiting Mesenchymal stem cells (MSCs) and delivering bioactive molecules. Challenges associated with inefficient use of stem cells, scaffolding techniques and poor understanding of the role of growth factors hinders the success of tissue engineering strategies. A major challenge with the use of autologous stem cells is its low proliferation and migratory capacity. Our lab previously established that using a biomaterial implant, autologous MSCs can be directed and recruited in …

Development Of Magnetic-Based Multi-Layer Microparticles For Stem Cell Isolation, Enrichment And Detachment, Sonia Santimano

Bioengineering Theses - Archive

Stem cells have been studied and used in several cell-based therapies for regenerative medicine, 3D tissue-engineered scaffolds, and in vitro models for drug screening and testing. For instance, cell based therapy via the use of stem cells like Endothelial Progenitor Cells (EPCs) to treat patients with cardiovascular diseases, including ischemic heart disease, in-stent restenosis, and peripheral arterial occlusive disease. In addition, Circulating Cancer Cells (CSCs) have been used as an indication of cancer progression-free survival and for studying the mechanisms of tumor formation, metastasis, and anti-cancer drug screening. Due to their extensive diagnostic and therapeutic potential, various techniques have been …

Quantification And Comparisons Of Motion Metrics For Finger Tapping Performed By Children With Cerebral Palsy Before And After Therapy With Two Motion Tracking Camera Systems, Ankita H. Chainani

Bioengineering Theses - Archive

The quantification of any improvements in the use of a paretic arm after children with cerebral palsy (CP) undergo rehabilitation is currently done by occupational therapists who administer a series of manual ability tests and assign a subjective score for each test task performed. In this work the hypothesis was explored of whether quantification of hand motion metrics by motion tracking while children with CP performed a hand tapping task could be used as a more quantitative surrogate for assessing how well these children control the use of their hand. To that end, two children with CP, both classified as …

Spectrophotometric Quantification Of Bilirubin In Sclera Of The Eye Using Visible Dlp® Hyperspectral Imaging, Naveen Balaji Balasubramanian

Bioengineering Theses - Archive

In clinical settings doctors strive to give best care to the patients by looking for methods to diagnose the illness early to intervene with the necessary treatment. In the case of patients with liver problems (e.g. cirrhosis, hepatitis) an early indicator of impaired liver function is an increased concentration of bilirubin in the blood circulation. Bilirubin concentration is currently quantified by blood sampling, which is invasive, and it would be desirable to have a technology that quantifies bilirubin non-invasively. The goal of this work was to help address this clinical need and develop a methodology for determining non-invasively a measure …

Antimicrobial Properties Of Citric Acid Based Polymers, Lee-Chun Su

Bioengineering Theses - Archive

A series of citric acid derived polymers synthesized in our lab were investigated and compared for their physiochemical and antimicrobial properties. We selected citric acid based polymers since citric acid is a product of natural metabolism. These polymers are not only biocompatible but also possess an antimicrobial effect. In polymer synthesis, citric acid (CA) provides profound functional groups available for binding and crosslinking to allow the controllable crosslinking degrees of polymers. A number of citric acid based polymers has been synthesized and studied for their chemical, mechanical, and biological characteristics for use in various biomedical applications. Since bacterial infections became …

Regenerative Peripheral Nerve Interfacing Of Sensory Modalities, Nilanjana T. Dutta

Bioengineering Theses - Archive

Peripheral neural interfaces (PNI) has proved potential to record motor commands for the control of these prosthetic limbs, together with stimulation of specific sensory axons, so as to transmit specific sensory sub-modalities. Although PNI is hypothesized to provide adequate sensory feedback, realizing this degree of specificity is not fully established. Recently, a regenerative multi-electrode interface (REMI) was reported to be capable of recording peripheral nerve activity from a transected nerve. This study is aimed at interfacing neural activity specific to sensory sub-modalities, such as thermal pain, mechanoception and limb stretching using the REMI, in a freely moving animal. In the …

Characterization Of Immune Response And Peripheral Nerve Regeneration Of Implanted Regenerative Multi-Electrode Interface Post-Subchronic Amputation, Camilo Andres Sanchez Useche

Bioengineering Theses - Archive

Interfacing high degree-of-freedom robotic prosthetics directly to the peripheral nervous system aims at improving the quotidian life of amputees. Despite advancements in robotics that have lead to human-like upper limb prosthetics, long-term interfacing has not been accomplished, thus voiding them from clinical use. Interfacing electrodes in the central nervous system fail due to the foreign body reaction and glial scar formation at the site of implantation. Concrete mechanisms for the failure of long-term Interfacing at the peripheral nervous level remain unclear. A regenerative multi-electrode interface (REMI) which allows for action potential recording as early as 7 days and provides support …

Development Of A Measurement System For Quantifying Ultrasound Field Distribution Of Different Transducers, Jayanth Kandukuri

Bioengineering Theses - Archive

Ultrasound has been widely used in many fields, such as nondestructive examination and medical imaging. Ultrasound is mostly characterized by its pressure and, dynamic pressure wave can be considered to be the foundation of ultrasound physics and imaging techniques. It is thus important for understanding ultrasound pressure properties to that of ultrasound intensity. Moreover, there are many applications that require mainly characterizing ultrasound pressure field (instead of intensity field alone). Therefore, reconstruction of an ultrasound pressure field is highly desirable not only for education but also for research. There may be some commercially available systems that can be used for …

Cell Permeabilization And Inhibition Of Voltage-Gated Ca²+ And Na+ Channel Currents By Nanosecond Pulsed Electric Fields, Vasyl Nesin, Angela M. Bowman, Shu Xiao, Andrei G. Pakhomov

Bioelectrics Publications

Previous studies have found that nanosecond pulsed electric field (nsPEF) exposure causes long-term permeabilization of the cell plasma membrane. In this study, we utilized the whole-cell patch-clamp method to study the nsPEF effect on currents of voltage-gated (VG) Ca²⁺ and Na⁺ channels (I_Ca and I_Na) in cultured GH3 and NG108 cells. We found that a single 300 or 600 ns pulse at or above 1.5-2 kV/cm caused prolonged inhibition of I_Ca and I_Na. Concurrently, nsPEF increased a non-inactivating leak current (I_leak), presumably due to the formation of nanoelectropores or larger …

Numerical Simulation And Experimentation Of Pulsatile Flows In Axisymmetric Arterial Models, Tadesse Gebreegziabher

Wayne State University Dissertations

ABSTRACT

NUMERICAL SIMULATION AND EXPERIMENTATION OF PULSATILE FLOWS IN AXISYMMETRIC ARTERIAL MODELS

by

TADESSE GEBREEGZIABHER

December 2011

Co-advisors: 1. Dr. Emmanuel Ayorinde 2. Dr. Trilochan Singh

Major: Mechanical Engineering

Degree: Doctor of Philosophy

The primary motivation for this dissertation is the fluid flow and structural response to unsteady blood flow in the human body. The research work is a synergistic merging of numerical simulation and experimentation. For the experiments, an all-encompassing, highly flexible experimental apparatus was designed and fabricated to facilitate a wide range of operating conditions, the range of which was chosen to accommodate mammalian cardiovascular system for both …

Curcumin-Loaded Magnetic Nanoparticles For Breast Cancer Therapeutics And Imaging Applications., Murali M. Yallapu, Shadi F. Othman, Evan Curtis, Nichole A. Bauer, Neeraj Chauhan, Deepak Kumar, Meena Jaggi, Subhash C. Chauhan

All Faculty Articles - School of Engineering and Computer Science

BACKGROUND: The next generation magnetic nanoparticles (MNPs) with theranostic applications have attracted significant attention and will greatly improve nanomedicine in cancer therapeutics. Such novel MNP formulations must have ultra-low particle size, high inherent magnetic properties, effective imaging, drug targeting, and drug delivery properties. To achieve these characteristic properties, a curcumin-loaded MNP (MNP-CUR) formulation was developed.

METHODS: MNPs were prepared by chemical precipitation method and loaded with curcumin (CUR) using diffusion method. The physicochemical properties of MNP-CUR were characterized using dynamic light scattering, transmission electron microscopy, and spectroscopy. The internalization of MNP-CUR was achieved after 6 hours incubation with MDA-MB-231 breast …

Optimization Of Bio-Impedance Sensor For Enhanced Detection And Characterization Of Adherent Cells, Dorielle T. Price

USF Tampa Graduate Theses and Dissertations

This research focuses on the detection and characterization of cells using

impedance-based techniques to understand the behavior and response of cells to internal/environmental changes. In combination with impedimetric sensing techniques, the biosensors in this work allow rapid, label-free, quantitative measurements and are very sensitive to changes in environment and cell morphology. The biosensor design and measurement setup is optimized to detect and differentiate cancer cells and healthy (normal) cells. The outcome of this work will provide a foundation for enhanced 3-dimensional tumor analysis and characterization; thus creating an avenue for earlier cancer detection and reduced healthcare costs.

The magnitude of …

Biophysical Assessment Of Single Cell Toxicity: Diesel Exhaust Particle-Treated Human Aortic Endothelial Cells, Kytai Truong Nguyen, Hao Xu, ​Yangzhe Wu, Anhong Zhou, Tian Yu, Timothy A. Gilbertson

Bioengineering Faculty Publications - Archive

Exposure to diesel exhaust particles (DEPs), a major source of traffic-related air pollution, has become a serious health concern due to its adverse influences on human health including cardiovascular and respiratory disorders. To elucidate the relationship between biophysical properties (cell topography, cytoskeleton organizations, and cell mechanics) and functions of endothelial cells exposed to DEPs, atomic force microscope (AFM) was applied to analyze the toxic effects of DEPs on a model cell line from human aortic endothelial cells (HAECs). Fluorescence microscopy and flow cytometry were also applied to further explore DEP-induced cytotoxicity in HAECs. Results revealed that DEPs could negatively impair …

Multifunctionality Of Indocyanine Green-Loaded Biodegradable Nanoparticles For Enhanced Optical Imaging And Hyperthermia Intervention Of Cancer, Kytai Truong Nguyen, Ronak H. Patel, Nimet L. Patel, Venkaiah C. Kavuri, Hanli Liu

Bioengineering Faculty Publications - Archive

The aim of this study was to develop and characterize multifunctional biodegradable and biocompatible poly lactic-co-glycolic acid (PLGA) nanoparticles loaded with indocyanine green (ICG) as an optical-imaging contrast agent for cancer imaging and as a photothermal therapy agent for cancer treatment. PLGA-ICG nanoparticles (PIN) were synthesized with a particle diameter of 246 11 nm, a polydispersity index of 0.10 0.03, and ICG loading efficiency of 48.75 5.48%. PIN were optically characterized with peak excitation and emission at 765 and 810 5 nm, a fluorescence lifetime of 0.30 0.01 ns, and peak absorbance at 780 nm. The cytocompatibility study of PIN …

Fabrication Of Small Diameter Vascular Graft Using Stacked Collagen Films, Sandeep Shah

Bioengineering Theses - Archive

Collagen I have been widely used in the field of vascular tissue engineering. They are characterized better for their interaction at the cellular level but are often limited as vascular graft due to their weak mechanical strength and thrombic property. The crosslinking chemicals or polymers support are used to overcome weak mechanical property. Crosslinking agents tend to have cytotoxic effects while blend with synthetic polymers have mismatch or compliancy issues inside the body. Here in this set of study, we used stacked collagen films and embedded drug delivery system within the film to construct small tubular conduits to meet the …

Self-Assmbled Lithography-Free Fabrication Of Microchannels And Microfluidics In Polymers, Wintana Tadesse Kahsai

Bioengineering Theses - Archive

Rapid, reliable and easy to implement approaches are needed for fabrication of circular microchannels in polymeric microfluidics. PDMS has been a choice of material in microfluidics and it is being used as prototype due to its unique property such as flexibility and transparency. Traditional method of fabrication such as photolithography and soft lithography are complicated and time consuming. In this thesis, a non-lithography and bottom-up self-assembled approach is shown. The resulting devices can have uses in many applications such as assays, biosensing, separation of mixtures, micro-mixing and bioreactors. This thesis presents novel approaches of manufacturing self-assembled microchannels in polydimethyleneoxide (PDMS) …

Alignment And Composition Of Laminin-Polycaprolactone Nanofiber Blends Enhance Peripheral Nerve Regeneration, Rebekah A. Neal, Sunil S. Tholpady, Patricia L. Foley, Nathan Swami, Roy C. Ogle, Edward A. Botchwey

School of Medical Diagnostics & Translational Sciences Publications

Peripheral nerve transection occurs commonly in traumatic injury, causing deficits distal to the injury site. Conduits for repair currently on the market are hollow tubes; however, they often fail due to slow regeneration over long gaps. To facilitate increased regeneration speed and functional recovery, the ideal conduit should provide biochemically relevant signals and physical guidance cues, thus playing an active role in regeneration. To that end, laminin and lamininpolycaprolactone (PCL) blend nanofibers were fabricated to mimic peripheral nerve basement membrane. In vitro assays established 10% (wt) laminin content is sufficient to retain neurite-promoting effects of laminin. In addition, modified collector …

Enhanced Killing Effect Of Nanosecond Pulse Electric Fields On Panc1 And Jurkat Cell Lines In The Presence Of Tween 80, Gaurav Basu, Bhargava Subhash Kalluri, Ahmet Can Sabuncu, Christopher J. Osgood, Michael W. Stacey

Bioelectrics Publications

We investigated the effects of nanosecond pulse electric fields (nsPEFs) on Jurkat and PANC1 cells, which are human carcinoma cell lines, in the presence of Tween 80 (T80) at a concentration of 0.18% and demonstarted an enhanced killing effect. We used two biological assays to determine cell viability after exposing cells to nsPEFs in the presence of T80 and observed a significant increase in the killing effect of nsPEFs. We did not see a toxic effect of T80 when cells were exposed to surfactant alone. However, we saw a synergistic effect when cells exposed to T80 were combined with the …

Probing Nanoparticle Interactions In Cell Culture Media, Ahmet C. Sabuncu, Janna Grubbs, Shizhi Qian, Tarek M. Abdel-Fattah, Michael W. Stacey, Ali Beskok

Bioelectrics Publications

Nanoparticle research is often performed in vitro with little emphasis on the potential role of cell culture medium. In this study, gold nanoparticle interactions with cell culture medium and two cancer cell lines (human T-cell leukemia Jurkat and human pancreatic carcinoma PANC1) were investigated. Gold nanoparticles of 10, 25, 50, and 100 nm in diameter at fixed mass concentration were tested. Size distributions and zeta potentials of gold nanoparticles suspended in deionized (DI) water and Dulbecco's Modified Eagle's Media (DMEM) supplemented with fetal calf serum (FCS) were measured using dynamic light scattering (DLS) technique. In DI water, particle size distributions …

The Use Of An In Vitro 3d Melanoma Model To Predict In Vivo Plasmid Transfection Using Electroporation, Benadette Marrero, Richard Heller

Bioelectrics Publications

A large-scale in vitro 3D tumor model was generated to evaluate gene delivery procedures in vivo. This 3D tumor model consists of a "tissue-like" spheroid that provides a micro-environment supportive of melanoma proliferation, allowing cells to behave similarly to cells in vivo. This functional spheroid measures approximately 1 cm in diameter and can be used to effectively evaluate plasmid transfection when testing various electroporation (EP) electrode applicators. In this study, we identified EP conditions that efficiently transfect green fluorescent protein (GFP) and interleukin 15 (IL-15) plasmids into tumor cells residing in the 3D construct. We found that plasmids …

Biomechanical Stability Of A Supra-Acetabular Pedicle Screw Internal Fixation Device (Infix) Vs External Fixation And Plates For Vertically Unstable Pelvic Fractures, Jonathan M. Vigdorchik, Amanda O. Esquivel, Xin Jin, King H. Yang, Ndidi A. Onwudiwe, Rahul Vaidya

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

We have recently developed a subcutaneous anterior pelvic fixation technique (INFIX). This internal fixator permits patients to sit, roll over in bed and lie on their sides without the cumbersome external appliances or their complications. The purpose of this study was to evaluate the biomechanical stability of this novel supraacetabular pedicle screw internal fixation construct (INFIX) and compare it to standard internal fixation and external fixation techniques in a single stance pelvic fracture model.

Methods

Nine synthetic pelves with a simulated anterior posterior compression type III injury were placed into three groups (External Fixator, INFIX and Internal Fixation). …

The Influence Of Membrane Cholesterol-Related Shear Stress Mechanosensitivity On Neutrophil Flow Behavior, Xiaoyan Zhang

Theses and Dissertations--Biomedical Engineering

Hypercholesterolemia is a dominant risk factor for a variety of cardiovascular diseases and involves a chronic inflammatory component in which neutrophil activity plays a critical role. Recently, fluid shear stress mechanotransduction has been established as a control mechanism that regulates the activity of neutrophils by reducing the formation of pseudopods and the surface expression of CD18 integrins, thereby rendering these cells rounded, deformable, and non-adhesive. This is critical for maintaining a healthy circulation, because chronically activated neutrophils not only release excess cytotoxic and degradative agents but also exhibit a reduced efficiency to pass through the small vessels of the microcirculation …

Virus Capsids As Nanoscale Delivery Vessels Of Photoactive Compounds For Site-Specific Photodynamic Therapy, Brian Alexander Cohen

Legacy Theses & Dissertations (2009 - 2024)

The research presented in this work details the use of a viral capsid as an addressable delivery vessel of photoactive compounds for use in photodynamic therapy. Photodynamic therapy is a treatment that involves the interaction of light with a photosensitizing molecule to create singlet oxygen, a reactive oxygen species. Overproduction of singlet oxygen in cells can cause oxidative damage leading to cytotoxicity and eventually cell death. Challenges with the current generation of FDA-approved photosensitizers for photodynamic therapy primarily stem from their lack of tissue specificity. This work describes the packaging of photoactive cationic porphyrins inside the MS2 bacteriophage capsid, followed …

Micropatterned Electrospun Nanofibrous Substrates As Scaffolds For Engineered Salivary Glands, David Alexander Soscia

Legacy Theses & Dissertations (2009 - 2024)

The salivary gland is a complex organ exhibiting a branching, 3-dimensional structure made up of acinar (saliva-producing), and ductal (saliva transporting and modifying) epithelial cells. The high surface area of the gland allows it to efficiently provide the mouth with saliva, maintaining oral cleanliness and comfort. Salivary gland hypofunction, a significant clinical problem often caused by the autoimmune disease Sjögren's syndrome or head and neck radiation for cancer patients, affects millions of Americans and is characterized by a loss of function of salivary gland acinar cells. Chronic xerostomia, or dry mouth, arises as a result of salivary gland hypofunction and …