Biomedical Engineering and Bioengineering Commons^™

Evaluation Of Alternative Solvents For Electrospinning Occluded Scaffolds To Model Intracranial Atherosclerotic Disease In Blood Vessel Mimics, Olivia D. Rankin

Master's Theses

Intracranial atherosclerotic disease (ICAD) is characterized by a buildup of fatty plaque within the walls of arteries supplying the brain, resulting in vessel narrowing, restricted blood flow, and increased risk of ischemic stroke. While various treatments exist for ICAD, most are accompanied by high recurrent stroke rates and other adverse events, highlighting the need for further investigation and models for pre-clinical testing. Tissue engineered Blood Vessel Mimics (BVMs), consisting of a polymer scaffold sodded with human vascular cells, serve as physiologically relevant in vitro models for vascular device testing. This thesis focused on the application of alternative solvents to a …

Electrospun Nanofiber Scaffolds For In Vitro 3d Tissue Engineering, Victoria E. Santillan, Samerender Nagam Hanumantharao, Stephanie Bule, Ronish M. Shrestha, Carter Rodzik, Alan Mendoza Estrada, Stephen L. Farias, Marina Tanasova, Smitha Rao

Michigan Tech Publications

Tissue engineering is widely used in research for investigating cellular proliferation, behavior, and responses to various stimuli. However, the predictive value of preclinical studies using cell culture plates is limited by the inability to recapitulate the complexity of the physiological microenvironment. Synthetic three-dimensional (3D) scaffolds can be engineered to mimic the complex morphology of the extracellular matrix of native tissues and can serve as physiologically relevant platforms for preclinical studies. In this study, 3D electrospun scaffolds were characterized to aid in breast cancer research. Unlike previous studies that focused primarily on scaffold fabrication or cell viability, this work systematically evaluates …

Tetramethylbenzidine Loaded Pva Nanofibers Strip For Visual Detection Of Hydrogen Peroxide Via Cu2+ Catalysis And Its Applications, Samar A. Salim

Nanotechnology Research Centre

Background Advancements in sensor technology have facilitated the development of cost-effective and highly sensitive sensors which have significantly improved the detection of biological analytes in various fields. This study presents a novel approach for the detection of hydrogen peroxide (H₂O₂), a critical analyte in both biological and environmental systems. A simple and sensitive colorimetric sensing platform was developed based on polyvinyl alcohol (PVA) nanofibers loaded with tetramethylbenzidine (TMB). Results The nanofibers were characterized using scanning electron microscopy, confirming the formation of smooth, spindle-shaped fibers with diameters from 324 to 551 nm. The colorimetric detection method utilized TMB, which undergoes oxidation …

Enhancing Wound Healing With Synergistic Dual-Drug Electrospun Roflumilast And L-Arginine Loaded Pla/Pva Nanofibers Through Fabrication, Optimization, And In Vivo Assessment, Samar A. Salim

Nanotechnology Research Centre

Current trends in improved wound management emphasize the development of dual-drug-loaded electrospun nanofibrous scaffolds. Herein, electrospun dual-drug loaded PLA/PVA nanofibrous scaffolds, incorporating roflumilast, a selective phosphodiesterase-4 inhibitor with anti-inflammatory activity, and L-arginine, a precursor to nitric oxide with stimulating activity towards wound healing and tissue regeneration, were developed. A dual-spinneret electrospinning process enabled the coloading of drugs in PLA and PVA phases. Scaffolds were characterized by SEM, FTIR, and XRD, showing consistent fiber morphology, and amorphous drug formation. FTIR analysis was performed to confirm drug–polymer compatibility and successful incorporation of roflumilast and L-arginine within the PLA/ PVA nanofibrous matrix. Swelling …

Fiber-Reinforced Composites For Vaginal Tissue Engineering Applications, Samyuktha S. Kolluru, Abir Hamdaoui, Annabella M. Mascot, Siobhan S. Sutcliffe, Jerry L. Lowder, Michelle L. Oyen, Samantha G. Zambuto

Mechanical Engineering Faculty Publications

The vagina is a fibromuscular tube-shaped organ that plays critical roles in menstruation, pregnancy, and female sexual health. Vaginal tissue constituents, including cells and extracellular matrix components, contribute to tissue structure, function, and prevention of injury and pathology. However, much microstructural function remains unknown, including how the fiber-cell and cell–cell interactions influence macromechanical properties. A deeper understanding of these interactions will provide critical information needed to reduce and prevent vaginal pathologies. Our objective for this work is to design a novel tissue-mimicking biomaterial for vaginal tissue engineering, and characterize its biological and mechanical performance in the vaginal microenvironment. We successfully …

Engineering Electrospun Pvdf Nanofibers For Next-Generation Wearable Bioelectronics, Reshmi Banerjee, Gymama Slaughter

Center for Bioelectronics Publications

Electrospun poly(vinylidene fluoride) (PVDF) and P(VDF-TrFE) nanofibers offer a mechanically flexible, high-surface-area platform for wearable bioelectronics, including piezoelectric sensing and self-powered operation. This review establishes a process–structure–property–performance framework for engineering electrospun PVDF- and P(VDF-TrFE)-based wearable systems. Relationships amongst precursor composition, electrospinning parameters, fiber morphology and alignment, crystalline phase formation, dipole orientation, and device-level piezoelectric performance are examined. Electrospinning is compared with other established fabrication methods including solution casting, spin coating, melt processing, phase inversion, and printing in terms of electroactive β-phase fraction, flexibility, scalability, manufacturing complexity, cost, and wearable-device suitability. Device architectures and performance are evaluated across pressure and strain …

Novel Electrospinning Techniques For Fabricating Scaffolds To Model Intracranial Atherosclerotic Disease In Tissue Engineered Blood Vessel Mimics, Isaac "Squeaky" Buentipo

Master's Theses

Novel Electrospinning Techniques for Fabricating Scaffolds to Model Intracranial

Atherosclerotic Disease in Tissue Engineered Blood Vessel Mimics

Isaac “Squeaky” Buentipo

Dr. Kristen Cardinal’s Tissue Engineering Lab at California Polytechnic State University specializes in fabricating customized vascular models, known as Blood Vessel Mimics (BVMs), for medical device testing. BVMs are simplified in vitro vascular models designed to bridge the gap between bench testing and in vivo evaluation of intravascular medical devices. BVMs are produced by combining a polymer scaffold with human vascular cells. Through novel scaffold fabrication techniques, such as silicone injection molding, silicone dip casting and electrospinning, the capabilities of …

Fabrication Of Docetaxel Loaded Pcl/Plga Electrospun Nanofibers For Lung Cancer Therapy, Rahul Tiwari, Fnu Pranav, Eswara N. Hanuma Kumar Ghali, Subhash Chauhan, Murali Yallapu, Luis Chavez

Research Symposium

Background: Electrospinning is a commonly employed method in tissue engineering due to its ability to produce nano-/microscale fibrous materials with mechanical and functional properties that mimic the extracellular matrix of living tissues. The general interest in electrospun fibrous matrices has recently expanded to cancer research both as scaffolds for in vitro cancer modeling and as patches for in vivo therapeutic delivery. This research aims to investigate the efficient delivery of anticancer drug in lung cancer treatment.

Methods: Three different biocompatible polymeric nanofibers (i.e. PCL fibers, PCL-PLGA mixed fibers, and PCL-PLGA tetra-layered fibers) loaded with docetaxel, were prepared using electrospinning technique. …

Multilayer Pva/Gelatin Nanofibrous Scaffolds Incorporated With Tanacetum Polycephalum Essential Oil And Amoxicillin For Skin Tissue Engineering Application, Ebrahim Soleiman-Dehkordi, Vahid Reisi-Vanani, Samanesadat Hosseini, Zahra Lorigooini, Vajihe Azimian Zvareh, Mahour Farzan, Elham Moghtadaie Khorasgani, Karen Lozano, Zohreh Abolhassanzadeh

Mechanical Engineering Faculty Publications

Wound infection is still an important challenge in healing of different types of skin injuries. This highlights the need for new and improved antibacterial agents with novel and different mechanisms of action. In this study, by electrospinning process Tanacetum polycephalum essential oil (EO), as a natural antibacterial and anti-inflammatory agent, along with Amoxicillin (AMX) as an antibiotic are incorporated into PVA/gelatin-based nanofiber mats individually and in combination to fabricate a novel wound dressing. Briefly, we fabricated PVA/gelatin loaded by Amoxicillin as first layer for direct contact with wound surface to protects the wound from exogenous bacteria, and then built a …

One-Pot Assembly Of Drug-Eluting Silk Coatings With Applications For Nerve Regeneration, Tanner D. Fink, Jessica L. Funnell, Ryan J. Gilbert, R. Helen Zha

Chemical and Biochemical Engineering Faculty Research & Creative Works

Clinical use of polymeric scaffolds for tissue engineering often suffers from their inability to promote strong cellular interactions. Functionalization with biomolecules may improve outcomes; however, current functionalization approaches using covalent chemistry or physical adsorption can lead to loss of biomolecule bioactivity. Here, we demonstrate a novel bottom-up approach for enhancing the bioactivity of poly (l-lactic acid) electro spun scaffolds though interfacial coassembly of protein payloads with silk fibroin into nano thin coatings. In our approach, protein payloads are first added into an aqueous solution with Bombyx mori-derived silk fibroin. Phosphate anions are then added to trigger coassembly of the payload …

Evaluation Of Polyvinyl Alcohol (Pva) For Electrospinning Utility In The Blood Vessel Mimic (Bvm) Lab, Logan Vandenbroucke

Master's Theses

Electrospinning has provided the opportunity to create extracellular matrix (ECM) mimicking scaffolds for the development of tissue-engineered constructs. Within Professor Kristen Cardinal’s Blood Vessel Mimic (BVM) Lab, at Cal Poly, there exists a constant demand for innovation and the expansion of polymer types and electrospinning capabilities for its BVM model. Along these lines, the BVM Lab has recently acquired two new electrospinning systems: the Spinbox, a commercially graded electrospinning system, and the Learn-By-Doing system, which was part of a recently completed thesis conducted by Jason Provol. Additionally, recently published literature has demonstrated polyvinyl alcohol (PVA) as a viable option for …

Cellulose Materials For Drug Delivery Applications, Reham Mohamed

Mechanical Engineering Theses

Non-healing wounds are a growing global public health concern due to inadequate or ineffective therapeutic products available. Cellulose-based biopolymers are attractive wound dressing materials due to their biocompatibility, biodegradability, non-toxicity, and cost-effectiveness. This study aims to design and fabricate solid dosage formulations using carboxymethyl cellulose (CMC) and ethyl cellulose (EC) to facilitate multi-stage releases of phenytoin (PHT) and tetracycline hydrochloride (TCH) from plain carriers, fibers/films composites, and layer-by-layer fiber composites. Results from in vitro drug release assays demonstrated a time-dependent release up to 8 hours from PHT-loaded EC fibers, while TCH-loaded CMC films exhibited a rapid release within 5 minutes. …

Advanced Processing Techniques For Electrospun Nanofibers: Investigating Annealing And Laser Zone-Drawing Effects On Material Characteristics, Matthew D. Flamini

Theses and Dissertations

Electrospun nanofibers hold potential for a wide range of commercial and scientific applications; however, their properties must be optimized through post-processing treatments to achieve optimal performance. This dissertation investigates the effects of annealing and laser zone-drawing on electrospun nanofiber properties. Annealing polycaprolactone nanofibers at 70°C results in the highest rate of crystallization and molecular alignment, impacting long-term stability and mechanical properties. A multivariate linear model incorporating crystallinity and molecular alignment predicts the material properties resulting from annealing under different conditions. Laser zone-drawing experiments reveal that polylactide fiber thinning under laser irradiation primarily occurs due to drawing rather than ablation. Steady-state …

Mechanical Properties And Morphological Alterations In Fiber-Based Scaffolds Affecting Tissue Engineering Outcomes, James Dolgin, Samerender Nagam Hanumantharao, Stephen Farias, Carl G. Simon, Smitha Rao

Michigan Tech Publications, Part 1

Electrospinning is a versatile tool used to produce highly customizable nonwoven nanofiber mats of various fiber diameters, pore sizes, and alignment. It is possible to create electrospun mats from synthetic polymers, biobased polymers, and combinations thereof. The post-processing of the end products can occur in many ways, such as cross-linking, enzyme linking, and thermal curing, to achieve enhanced chemical and physical properties. Such multi-factor tunability is very promising in applications such as tissue engineering, 3D organs/organoids, and cell differentiation. While the established methods involve the use of soluble small molecules, growth factors, stereolithography, and micro-patterning, electrospinning involves an inexpensive, labor …

An Assessment Of Blood Vessel Remodeling Of Nanofibrous Poly(Ε-Caprolactone) Vascular Grafts In A Rat Animal Model, Jana Horakova, Tereza Blassova, Zbynek Tonar, Connor Mccarthy, Katerina Strnadova, David Lukas, Petr Mikes, Patrick Bowen, Roger J. Guillory Ii, Megan C. Frost, Jeremy Goldman

Michigan Tech Publications, Part 1

The development of an ideal vascular prosthesis represents an important challenge in terms of the treatment of cardiovascular diseases with respect to which new materials are being considered that have produced promising results following testing in animal models. This study focuses on nanofibrous polycaprolactone-based grafts assessed by means of histological techniques 10 days and 6 months following suturing as a replacement for the rat aorta. A novel stereological approach for the assessment of cellular distribution within the graft thickness was developed. The cellularization of the thickness of the graft was found to be homogeneous after 10 days and to have …

Synthesis And Processing Of Pcl And Irdye Nanoparticles For Application In Drug Release Mechanism, Michael Adeniyi

College of Graduate Studies: Theses & Dissertations

The objective of this study is to produce core-shell nanoparticles utilizing PCL and IRDye and investigate the nanoparticle release mechanism. Biodegradable polymer, Polycaprolactone (PCL), was electrosprayed separately with two types of IRDye, NHS and Dextran Texas red. The solution of PCL was formed by mixing PCL in a solution of 9.47ml Acetic Acid, 9.47ml Formic Acid, and 1.05ml Trifluoroethanol, following a ratio of 9:9:1. The two solutions of IRDye were prepared by mixing 2mg of the IRdye with 20ml of DMF at a rate of 0.1mg/ml.

The NHS IRDye was electrosprayed coaxially with PCL and the Dextran Texas red dye …

Promotion Of Human Schwann Cell Proliferation Using Heparin/Collagen Coated Nerve Conduits, John Magness

Chemical Engineering Undergraduate Honors Theses

Often in the aftermath of an injury or surgery, the sense of touch and muscle control is lost in the affected area as nerves are damaged or severed and fail to grow back completely. The regeneration of the nerve cells can be promoted by treating the nerves with nerve conduits. Nerve conduits are hollow cylinders of bio-compatible materials that can be surgically implanted to the disconnected nerve to promote and direct the growth of nerves. The objectives of this research are to investigate the ability of nerve conduits treated with layer-by-layer coatings to promote the growth of Schwann cells, to …

Enhancement Of Electrospun Nanofiber Properties Via Automated Track Post-Draw Processing, David Anthony Brennan

Theses and Dissertations

Electrospinning is an alternative manufacturing method, capable of producing fibers with nanoscale diameters from a wide range of different polymers in a process which is relatively simple and inexpensive in comparison to other forms of nanofiber production. This has made electrospinning the subject a great deal of research as a method of producing nanofibers for various high-performance applications. However, electrospun nanofiber tensile strength is weak in comparison to conventional fibers of the same material, preventing widespread use and marketization. This disparity in mechanical strength is attributed to poor polymer chain alignment in individual fibers, caused by the absence of a …

Design Of An Affordable Rotating Drum Electrospinner For Classroom Education, Peder Solberg

The Journal of Undergraduate Research

Electrospinning is a technology used to generate small fibers down to nano-scale size. This method of fiber creation has been around for many years. However, in recent years electrospinning has found increased applications, especially in the area of tissue engineering due to its ability to create fibers with properties similar to the extracellular matrix in tissue. An electrospinning platform can illustrate concepts of engineering, electro-mechanical system design, manufacturing, and biomedical applications in one single package. Hence, it provides an excellent opportunity to integrate into secondary (middle and high school) and post-secondary (undergraduate) technology education.

Furthermore, just as integration of 3D …

Development Of Cellulose Acetate-Based Scaffold For Bone Tissue Engineering Applications, Ruhit Sinha

Electronic Theses and Dissertations

Cellulose Acetate (CA) based biomaterials are being used as substrates for bone ingrowth applications due to their nontoxic and nonirritant nature coupled with optimum morphology and stiffness. Electrospinning with additives and/or post-treatment has emerged as a viable protocol to further improve mechanical properties of CA and expand its utility. Herein, we highlight the role of potassium chloride (KCl) in association with airdrying to enhance the elastic modulus and tensile strengths of CA fibers. Salt aggregation in between fibers is observed through Scanning Electron Microscopy (SEM), however, Fourier-transform infrared (FTIR) analysis signifies the interactions between K+ ions and acetyl groups. The …

Artificial Synthetic Scaffolds For Tissue Engineering Application Emphasizing The Role Of Biophysical Cues, Samerender Nagam Hanumantharao

Dissertations, Master's Theses and Master's Reports

The mechanotransduction of cells is the intrinsic ability of cells to convert the mechanical signals provided by the surrounding matrix and other cells into biochemical signals that affect several distinct processes such as tumorigenesis, wound healing, and organ formation. The use of biomaterials as an artificial scaffold for cell attachment, differentiation and proliferation provides a tool to modulate and understand the mechanotransduction pathways, develop better in vitro models and clinical remedies. The effect of topographical cues and stiffness was investigated in fibroblasts using polycaprolactone (PCL)- Polyaniline (PANI) based scaffolds that were fabricated using a self-assembly method and electrospinning. Through this …

Electrospun Nanofiber Scaffolds As A Platform For Breast Cancer Research, Carolynn Que

Dissertations, Master's Theses and Master's Reports

Tumorigenesis is a complex process involving numerous cellular signaling cascades and environmental factors. Here, we report the fabrication of 3D scaffolds with different morphologies obtained by to study cancer cell proliferation and migration. Using an FDA approved, biocompatible and biodegradable polymer Polycaprolactone (PCL), we electrospun nanofiber scaffolds having mesh, aligned, and honeycomb morphologies. The role of the morphology and cellular preferences to nutrition in cell adhesion and proliferation was assessed using scaffolds obtained by electrospinning PCL with fluorescent fructose-like molecular probes. Cell viability, cell morphology, localized cellular growth as related to scaffold morphology and availability of the fructose-like molecular probes …

Multi-Functional Electrospun Nanofibers From Polymer Blends For Scaffold Tissue Engineering, Samerender Nagam Hanumantharao, Smitha Rao

Michigan Tech Publications, Part 1

Electrospinning and polymer blending have been the focus of research and the industry for their versatility, scalability, and potential applications across many different fields. In tissue engineering, nanofiber scaffolds composed of natural fibers, synthetic fibers, or a mixture of both have been reported. This review reports recent advances in polymer blended scaffolds for tissue engineering and the fabrication of functional scaffolds by electrospinning. A brief theory of electrospinning and the general setup as well as modifications used are presented. Polymer blends, including blends with natural polymers, synthetic polymers, mixture of natural and synthetic polymers, and nanofiller systems, are discussed in …

Nano Fab Lab 63, Brian K. Deemer, Josh Clemons, Nick Brodine, Delaney Fitzsimmons

Mechanical Engineering

Lawrence Livermore National Laboratories (LLNL) has several steps in the production process for ceramic nanofiber tubes that they would like to improve - electrospinning, cutting, rolling, sealing and heat treating. We undertook the challenge to deliver LLNL with a semi-automated process that efficiently integrates the steps of cutting, rolling, and sealing to save time and improve control over end dimensions. In this document, we discuss the technical background of the manufacturing steps currently followed to create nanofiber tubes, identify which steps are incorporated in our prototype and explain how they will interface with one another, define the design requirements, present …

Self-Assembly Of 3d Nanostructures In Electrospun Polycaprolactone-Polyaniline Fibers And Their Application As Scaffolds For Tissue Engineering, Samerender Nagam Hanumantharao, Carolynn Que, Smitha Rao

Department of Biomedical Engineering Publications

The fabrication of synthetic scaffolds that mimic the microenvironment of cells is a crucial challenge in materials science. The honeycomb morphology is one such bio-mimicking structure that possesses unique physical properties and high packing efficiency in a 3-dimensional space. Here, we present a novel method for electrospinning polycaprolactone-polyaniline with continuous, self-assembled, uniform, interwoven nanofibers forming patterns without the use of templates or porogens. By using the approach presented here, unique architectures mimicking the natural mechanical anisotropy of extracellular matrix were created by varying the electric field. Adult human dermal fibroblasts (HDFa) cells were successfully cultured on the nanofiber scaffolds without …

Identifying And Reducing Variability, Improving Scaffold Morphology, And Investigating Alternative Materials For The Blood Vessel Mimic Lab Electrospinning Process, Evan M. Dowey

Master's Theses

The work of the Cal Poly Tissue Engineering Lab is primarily focused on the fabrication, characterization, and improvement of “Blood Vessel Mimics” (BVMs), tissue engineered constructs used to evaluate cellular response to vascular medical devices. Currently, cells are grown onto fibrous, porous tubes made using an in-house electrospinning process from PLGA, a biocompatible co-polymer. The adhesion and proliferation of cells in a BVM is reliant on the micro-scale structure of the PLGA scaffold, and as such it is of great importance for the electrospinning process to consistently produce scaffolds of similar morphologies. Additionally, it has been shown that cell proliferation …

Evaluation Of Procedures To Quantify Solvent Retention In Electrospun Fibers And Facilitate Solvent Removal, Anthony R. D'Amato, Nicholas J. Schaub, Jesus M. Cardenas, Erich Franz, Deniz Rende, Alexis M. Ziemba, Ryan J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Electro spun fiber scaffolds crafted from polyesters are studied extensively for potential tissue engineering applications. For translation of electro spun fibers into the clinic, the FDA requires analysis and quantification of any organic solvent that may be retained in the fibers since many organic solvents can negatively affect cells and tissues. If a significant amount of solvent is retained, then developing procedures for efficient solvent removal may enhance the clinical potential of these materials. In this study we use fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and nuclear magnetic resonance spectroscopy (NMR) to analyze solvent retention. A correlative analysis …

Modulating The Innate Immune Response To Electrospun Scaffolds And Polymer Degradative Byproducts, Daniel Abebayehu

Theses and Dissertations

Implanted biomaterials often induce inflammation that frequently leads to the foreign body response, fibrosis, and the failure of the implant. Thus, it is important to evaluate how cells interact with materials to promote a more regenerative response. It is critical to determine how to modulate the response of tissue resident innate immune cells, as they are among the first cells to interact with implanted materials. Among tissue resident innate immune cells are mast cells, which are inflammatory sentinels that degranulate and orchestrate the fate of other cell populations, such as monocytes/macrophages and lymphocytes. Mast cells have also been reported to …

Development Of An Electrospun And 3d Printed Cellular Delivery Device For Dermal Wound Healing, Ryan M. Clohessy

Theses and Dissertations

The goal of this research was to develop a system of individualized medicine that could be applied to dermal wounds serving as a wound dressing and synthetic extracellular matrix while delivering stem cells to the wound bed. First, fabrication parameters for electrospinning polymer fibers were determined. This involved evaluating fiber morphology with respect to polymer selection and solution concentration. Next, construct fabrication was examined to produce an integrated void space, or cargo area, suitable to maintain stem cells. In vitro studies to ensure stem cell viability and phenotype were conducted, and results supported the notion that cells could be administered …

Development Of A Programmed Electrospun Three Dimensional (3d) Nanofiber Collecter And It’S Application To Orthopedic Implant Coatings, Liang Chen

Wayne State University Dissertations

Orthopedic implants might not directly unite with bones especially in compromised patients even if they have been appropriately fixed. The lack of early osseointegration would lead to the failure of the orthopedic implant. A “bone-like” implant surface is urgently needed to accelerate osseointegration. Electrospun nanofiber (NF) is a promising implant coating due to its highly porous nanoscale structure. It mimics the collagen I nanofibrous network of bone tissue; meanwhile it has been widely used as a drug delivery device. However, its compact and dense structure is not ideal for cell growth. Our strategy was to develop a functional three-dimensional (3D) …