Finite Element Analysis Of 3d-Printed Pcl Scaffolds, Ireolu K. Orenuga, Joao Soares, Phillip D. Glass, Daeha Joung Ph.D.

Undergraduate Research Posters

Finite Element Analysis of 3D-printed PCL Scaffolds for Synergizing Cellular Micro-Environment and Mechanical Stimuli to Enhance Engineered Tissue Growth in Vitro

Ireolu Orenuga,1 Phillip Glass,2 Daeha Joung,2 Joao S. Soares1

1. Department of Mechanical and Nuclear Engineering, College of Engineering, Virginia Commonwealth University
2. Department of Physics, College of Humanities & Sciences, Virginia Commonwealth University

Introduction: Tissue engineering aims to create viable and functional engineered tissues via biodegradable scaffolds and autologous cells. Scaffolds play an essential part in organizing the architecture of developing tissues and aid in the proper function of implants acutely by serving as mechanical support and long-term by …

Therapeutic Injectable Iron-Chelating Hydrogels, Debbie Campbell-Rance

Theses and Dissertations

ABSTRACT

Therapeutic Injectable Iron-Chelating Hydrogels for Improved Central Nervous System Regeneration

By

Debbie S. Campbell-Rance

A dissertation submitted in partial fulfillment of the requirements of the degree of Doctor of Philosophy at Virginia Commonwealth University 2021.

Director: Xuejun Wen, M.D., Ph.D., AIMBE Fellow, Alice T. and William H. Goodwin Jr. Endowed Chair Professor in Regenerative Medicine, Institute for Engineering and Medicine, Department of Chemical and Life Science Engineering

Severe traumatic brain and spinal cord injuries are major global public health and socioeconomic problems in terms of mortality and morbidity. Currently there are two main lines of treatment under development for …

A Highly Conductive, Flexible, And 3d-Printable Carbon Nanotube-Elastomer Ink For Additive Bio-Manufacturing, Andy Shar, Phillip Glass, Daeha Joung Ph.D.

Undergraduate Research Posters

The synthesis of a highly conductive, flexible, 3D-printable, and biocompatible ink has been of great interest in the field of bio-based additive manufacturing. Various applications include ultra-sensitive, microscale tactile sensors, patient-customizable scaffolds for cardiac and nerve tissue regeneration, and flexible electrocardiogram (ECG) electrodes. Here, a novel elastomeric carbon nanocomposite is presented consisting of amino-functionalized carbon nanotubes (CNT-NH₂) homogenously dispersed in a one-part room-temperature vulcanizing (RTV) silicone matrix. The use of acetone as a swelling solvent aids in electrical percolation through the elastomer matrix. CNT-NH₂ ratios can be tuned to fit various needs; higher tensile strength is favored …

Nature-Inspired Material Strategies Towards Functional Devices, Sayantan Pradhan

Theses and Dissertations

Naturally sourced, renewable biomaterials possess outstanding advantages for a multitude of biomedical applications owing to their biodegradability, biocompatibility, and excellent mechanical properties. Of interest in this dissertation are silk (protein) and chitin (polysaccharide) biopolymers for the fabrication of functional biodevices. One of the major challenges restricting these materials beyond their traditional usage as passive substrate materials is the ability to combine them with high-resolution fabrication techniques. Initial research work is directed towards the fabrication of micropatterned, flexible 2D substrates of silk fibroin and chitin using bench-top photolithographic techniques. Research is focused on imparting electrochemical properties to silk proteins using conducting …

Decellularized Matrices Effect On The Adaptive Immune Response, Kegan Sowers

Theses and Dissertations

Decellularized extracellular matrices have been a growing area of interest in the biomedical engineering fields of tissue engineering and regenerative medicine.As these materials move toward clinical applications, the immune response to these materials will be a driving force toward their success in clinical approaches. Fully digested decellularized matrix constructs derived from porcine liver, muscle and lung were created to test the adaptive immune response. Hydrogel characterization ensured that the materials had relatively similar stiffness levels to reduce variability, and in vitro studies were conducted. Each individual construct as well as a gelatin control were plated with a co-culture of macrophages …

Engineering Surface Properties To Modulate Inflammation And Stem Cell Recruitment Through Macrophage Activation, Kelly M. Hotchkiss

Theses and Dissertations

Biomaterials are becoming the most commonly used therapeutic method for treatment of lost or damaged tissue in the body. Metallic materials are chosen for high strength orthopaedic and dental applications. Titanium (Ti) implants are highly successful in young, healthy patients with the ability to fully integrate to surrounding tissue. However the main population requiring these corrective treatments will not be healthy or young, therefore further research into material modifications have been started to improve outcomes in compromised patients. The body’s immune system will generate a response to any implanted material, and control the final outcome. Among the first and most …

Polysaccharide-Based Shear Thinning Hydrogels For Three-Dimensional Cell Culture, Vasudha Surampudi

Theses and Dissertations

The recreation of the complicated tissue microenvironment is essential to reduce the gap between in vitro and in vivo research. Polysaccharide-based hydrogels form excellent scaffolds to allow for three-dimensional cell culture owing to the favorable properties such as capability to absorb large amount of water when immersed in biological fluids, ability to form “smart hydrogels” by being shear-thinning and thixotropic, and eliciting minimum immunological response from the host. In this study, the biodegradable shear-thinning polysaccharide, gellan-gum based hydrogel was investigated for the conditions and concentrations in which it can be applied for the adhesion, propagation and assembly of different mammalian …

Design Of Engineered Biomaterial Architectures Through Natural Silk Proteins, Nicholas Kurland

Theses and Dissertations

Silk proteins have provided a source of unique and versatile building blocks in the fabrication of biomedical devices for addressing a range of applications. Critical to advancing this field is the ability to establish an understanding of these proteins in their native and engineered states as well as in developing scalable processing strategies, which can fully exploit or enhance the stability, structure, and functionality of the two constituent proteins, silk fibroin and sericin. The research outlined in this dissertation focuses on the evolution in architecture and capability of silks, to effectively position a functionally-diverse, renewable class of silk materials within …

Engineering Of Polyamidoamine (Pamam) Dendrimers For Gene And Drug Delivery, Quan Yuan

Theses and Dissertations

Dendrimers are a class of polymers with a highly branched, three-dimensional architecture composed of an initiator core, several interior layers of repeating units and multiple surface groups. They have been recognized as the most versatile compositionally and structurally controlled nanoscale building blocks throughout the fields of engineering, materials science, chemistry, and biology, and they have been widely investigated for drug and gene delivery. Polyamidoamine (PAMAM) dendrimers have inherent properties for gene delivery because of their high buffering capacity, polycationic surface and numerous surface groups for biofunctionlization. This dissertation is organized into four independent sections. The first section investigates a series …

Angiogenic Potential Of Human Macrophages On Electrospun Bioresorbable Vascular Grafts, Koyal Garg

Theses and Dissertations

The aim of this study was to investigate macrophage interactions with electrospun scaffolds and quantify the expression of vital angiogenic growth factors in vitro. This study will further help in evaluating the potential of these electrospun constructs as vascular grafts for tissue repair and regeneration in situ. Human peripheral blood macrophages were seeded in serum free media on electrospun (10 mm) discs of polydioxanone (PDO), elastin and PDO:elastin blends (50:50, 70:30 and 90:10). The growth factor secretion was analyzed by ELISA. Macrophages produced high levels of vascular endothelial growth factor (VEGF) and acidic fibroblast growth factor (aFGF). Transforming growth factor …