Biomaterials Commons^™

Metabolic Responses Of Adipose-Derived Stem Cells In Collagen I Hydrogels, Caroline R. King

Biological Sciences Undergraduate Honors Theses

Peripheral nerve injury affects approximately 44 in 1 million people in the United States every year and can lead to incomplete nerve recovery and loss of motor and sensory function. A significant amount of energy is required for nerve injury repair. A lack of energy allocation to the injury site hinders repair. Current treatments include hollow nerve guidance conduits, decellularized nerve grafts, and autografts. However, they are limited by factors such as donor site morbidity and sustained immunosuppressive treatments. Using three-dimensional collagen I hydrogels laden with adipose-derived stem cells (ASCs) can assist in neural regeneration. Three-dimensional collagen scaffolds aim to …

Dust Analyses In Ventilation Ducts, Karolina Vyhlidalova, Petr Vlček, Olga Rubinová, Jiří Bernard

Journal of Sustainable Construction Materials and Technologies

The paper describes the importance of monitoring the dust in the atmosphere of human life. It deals with the issue of dust in air ducts, approaching the methods that can be used to detect the amount of dust. For conditions for buildings in the Czech Republic there is created the methodology of quantitative and qualitative evaluation of dust sediment for the needs of HVAC and other building surfaces. The scale for visual evaluation was created and it has been elaborated the assessment of kind of particles contained in dust.

Assessment Of Long Time Approximation Equation To Determine Thermal Conductivity Of High Porous Materials With Nss Probe, Hussein Humaish, Bastien Ruet, Laurent Marmoret, Hassen Beji

Journal of Sustainable Construction Materials and Technologies

Recent economic changes have increased the focus on energy conservation in buildings. Improve insulation represents one of the biggest challenge to save energy. The TP02 Huksefux® Non Steady State Probe (NSSP) has been used to determine the thermal conductivity of the building insulation materials. Usually, the long term approximation equation (linear form) is applied to determine the thermal conductivity when using hot wire techniques. Long term approximation has been successfully used to characterize glycerol: a fluid which doesn’t present contact resistance and porosity. But, an S-shaped appears for more porous materials. So to generalize the possibility of using this method, …

Determining The Wound Closure Capabilities Of A Biological Engineered Blood Vessel For Hd Access, Brianna Regan, Alex Dumitru, Mai Lam

Medical Student Research Symposium

End stage renal disease (ESRD) is a prominent chronic condition with dialysis as a primary treatment option. Dialysis necessitates implementation of an access point, with the gold standard being an AV fistula which possesses multiple shortcomings. Alternative access points, namely synthetic grafts, do not allow wound healing characteristics. This work aims to explore how a tissue engineered vascular graft (TEVG) may be able to address these issues by allowing a long-term access point for HD that can close puncture wounds.

The effects of growth factors on our cells were tested preliminarily by means of a scratch assay on plates of …

Fabricating Silver-Ceria Polymer Nanocomposite Scaffolds For Biomedical Therapeutic Applications, Shreya S. Pawar

Honors Undergraduate Theses

Improper healing of bone fractures and limited regeneration of bone following bone tumor resection remain a prevalent complication worldwide. Long-term effects of this include joint instability, limited movement, and arthritis. Bone infections (osteomyelitis), reactive oxygen species (ROS) generation via excessive inflammation, and underlying conditions such as osteoporosis can contribute to suboptimal bone tissue regeneration. ROS accumulation stimulates osteoblast apoptosis, while promoting osteoclast differentiation. These processes inhibit mineralization and osteogenesis. Conventional therapeutics involve the utilization of drugs and bone grafts. However, these approaches pose limitations and can result in subsequent complications. Microbial infections, ROS accumulation, and excessive inflammations are factors that …

Advances In Bacterial Cellulose-Based Scaffolds For Tissue Engineering: Review, Rewati Raman Ujjwal, Gymama Slaughter

Center for Bioelectronics Publications

Bacterial cellulose (BC) has emerged as a highly versatile and promising biomaterial in tissue engineering, with potential applications across skin, bone, cartilage, and vascular regeneration. Its exceptional properties like high mechanical strength, superior biocompatibility, excellent moisture retention, and inherent ability to support cell adhesion and proliferation, make BC particularly effective for wound healing and skin regeneration. These attributes accelerate tissue repair and foster new tissue formation, highlighting its value in skin-related applications. Additionally, BC's capacity to support osteogenic differentiation, combined with its mechanical robustness, positions it as a strong candidate for bone tissue engineering, facilitating regeneration and repair. Recent advancements …

The Bacteriostatic, Regenerative, And Immunomodulatory Properties Of Extracellular Matrix Particles For Lung Injury, Keera P. Rhoads

Theses and Dissertations

Acute respiratory distress syndrome (ARDS) is a prevalent, life-threatening lung condition, affecting nearly 200,000 Americans annually, with a 40% international mortality rate. There is no cure for ARDS, and current pharmacological treatments have limited effectiveness. Symptoms can be mitigated with mechanical ventilation, though this often leads to ventilator-induced lung injuries (VILI) and puts critically ill patients at risk of infections, including ventilator-associated pneumonia (VAP). A promising therapeutic is the extracellular matrix (ECM), a complex network of structural proteins and bioactive molecules that has been shown to have anti-inflammatory properties and prevent fibrosis. We aim to utilize the regenerative and immunomodulatory …

Demonstrating Feasibility Of Ultrasound-Sensitive Microbubbles Delivery To Treat Disruptions In The Blood Brain Barrier Endothelium, Rubens Jourdain

Theses and Dissertations

Vascular cognitive impairment and dementia (VCID) is one of the main causes of dementia. VCID is caused by age and other genetic factors that lead to disruptions in the blood brain barrier (BBB) and allow blood components to enter the brain. The currently available treatments of VCID include opening the BBB with high-frequency-ultrasound to deliver drugs to the brain. However, this only treats the already developed disease. Consequently, we developed a new drug delivery system whose goal is to restore the brain capillary endothelial cells (BCEC) lining the blood vessel. The objective of this study was to demonstrate the feasibility …

Advancing Biofabrication Methodologies To Develop Biomimetic Tissue Scaffolds For Musculoskeletal Applications, Nashaita Yezdi Patrawalla

Theses and Dissertations

Musculoskeletal injuries impose a significant global burden, affecting millions and generating an economic toll exceeding $14 billion. Tissue engineering has gained traction as a promising strategy offering potential for functional restoration of damaged musculoskeletal tissues. This research aims to advance biofabrication techniques for generation of biomimetic tissue scaffolds, by optimizing scaffold design and modulating fabrication process parameters to generate scaffolds for musculoskeletal regeneration with application-specific tailored properties. In this realm, collagen-based biomaterials have been extensively investigated for tendon and ligamentous applications, and in combination with bioceramics incorporated into the collagen framework to produce composite scaffolds that better recapitulate the native …

Multifunctional Peptides To Improve Nucleic Acid Delivery For Ovarian Cancer Treatment, Kharimat Lora Alatise

All Dissertations

RNA interference (RNAi) therapies, such as small interfering RNA (siRNA), offer a high-precision approach to reducing the expression of disease-promoting genes with minimal off-target effects. For aggressive diseases like ovarian cancer, RNAi therapy can serve as a robust treatment modality if delivered successfully. Over 70% of ovarian cancer patients are diagnosed in stages three and four, where the disease becomes more difficult to treat. High relapse rates and drug resistance in these stages demonstrate the need for novel strategies to sensitize tumors to chemotherapy, making siRNA a promising avenue for targeting resistance-associated oncogenes.

However, the delivery of siRNA remains a …

Engineered Nucleic-Acid Binding Intrinsically Disordered Proteins For Biomedical Applications, Telmo Diez Perez

Biomedical Engineering ETDs

This dissertation explores the use of intrinsically disorder proteins (IDPs) in biomedical applications related to the detection and biosensing of nucleic-acid species. We engineer several low critical solution temperature (LCST) nucleic-acid binding elastin-like polypeptides (ELPs) as model IDPs and study their potential in biomedical application via interactions with short single-stranded (ss) DNA, tRNA and viral RNAs. First, we engineer a simple polycationic ELP capable of recruiting DNA on demand in a DNA-protein-rich condensate via LLPS. Moreover, we develop a modified Flory-Huggins theory to quantify the partitioning of DNA and protein upon coacervate formation with and without salts. We then design …

Innovative 4d Printing Of Biomimetic Collagen-Tcp Scaffolds For Bone Regeneration, Karly Morgan Liebendorfer

Theses and Dissertations

Bone tissue engineering (BTE) is a promising alternative approach to autografts and allografts when treating various bone diseases and disorders. BTE enables the fabrication of biocompatible, biomimetic, and osteo-stimulating constructs for the repair and regeneration of damaged bone tissue. The native bone environment primarily consists of anisotropic type 1 collagen (organic) and hydroxyapatite nanocrystals (inorganic). Composite biomimetic scaffolds fabricated by combining collagen with bioceramics have shown immense promise for BTE applications. Prior work has reported on different biofabrication methods to synthesize collagen-based composite scaffolds for use in BTE applications. However, to date, a customizable 3D composite scaffold that resembles the …

Scaffold-Free Development Of Multicellular Tumor Spheroids With Spatial Characterization Of Structure And Metabolic Radial Profiles, Shelby N. Bess, Gaven K. Smart, Matthew J. Igoe, Timothy J. Muldoon

Biomedical Engineering Faculty Publications and Presentations

Purpose

In vitro assays are essential for studying cellular biology, but traditional monolayer cultures fail to replicate the complex three-dimensional (3D) interactions of cells in living organisms. 3D culture systems offer a more accurate reflection of the cellular microenvironment. However, 3D cultures require robust and unique methods of characterization.

Methods

The goal of this study was to create a 3D spheroid model using cancer cells and macrophages, and to demonstrate a custom image analysis program to assess structural and metabolic changes across spheroid microregions.

Results

Structural characterization shows that cells at the necrotic core show high normalized fluorescence intensities of …

Manufacturing Silicone In-House For The Creation Of Customized Neurovascular Blood Vessel Mimics, Jacob Wilbert Perisho

Master's Theses

The Tissue Engineering Lab at California Polytechnic State University San Luis Obispo focuses on creating tissue-engineered Blood Vessel Mimics (BVMs) designed for the preclinical testing of neurovascular devices. These BVMs are composed of silicone models, representing anatomically accurate neurovasculatures, that are sodded with vascular cell types and then cultivated in bioreactors (which maintain physiologic conditions). These silicone models are currently sourced externally from industry partners, so the primary goal of this thesis was to develop the means and methods for the Tissue Engineering Lab to manufacture silicone models in-house.

The first aim of this thesis was to develop and explore …

Environment And Response Of 3d-Encapsulated Mesenchymal Stem Cells To Mechanical Loading, Augustus Greenwood

McKelvey School of Engineering Graduate Student Theses & Dissertations

This thesis explores the micromechanical environment induced when cyclically compressing hydrogels via finite element modeling and experimentally on the impact of loading on mesenchymal stem cells (MSCs) when encapsulated withing 3D hydrogel matrices. Degenerative joint diseases, characterized by cartilage degradation, present significant challenges due to cartilage's limited self-repair capacity. Innovative approaches, including stem cell-based therapies and engineered biomaterials, have emerged as promising strategies for cartilage repair and regeneration. This work specifically investigates the calibration of a bioreactor, the uniformity of load response across the hydrogel constructs via finite element modeling (FEM), and the stress response of MSCs subjected to various …

Novel Nucleus Pulposus Biomaterial Development And Low Field Mri Assessment For Intervertebral Disc Degeneration, Mario Krussig

All Dissertations

Intervertebral disc degeneration (IVDD) is a prominent pathology in the modern world that causes debilitating pain for many patients. The onset of IVDD occurs in the nucleus pulposus (NP). NP biomaterials will play a vital role in mitigating the progression of IVDD. Within this work, we sought to synthesize a solubilized extracellular matrix (ECM)-based NP biomaterial. Utilizing pepsin or urea extraction, bovine NP ECM was successfully solubilized (SBNPs). SBNP formulations were characterized biochemically, evaluated for cytotoxicity, and down-selected for front-running formulations. Leading candidate SBNPs were incorporated into an alginate bead biomaterial model to determine the potential bioactivity with human adipose-derived …

Low Impedance, Durable, Self-Adhesive Hydrogel Epidermal Electrodes For Electrophysiology Recording, Naiyan Wu

McKelvey School of Engineering Graduate Student Theses & Dissertations

Traditional electrodes used for electrophysiology recording, characterized by their hard, dry, and inanimate nature, are fundamentally mismatched with the soft, moist, and bioactive characteristics of biological tissues, leading to suboptimal skin-electrode interfaces. Hydrogel materials, mirroring the high water content and biocompatibility of biological tissues, emerge as promising candidates for epidermal electronic materials due to their adjustable physicochemical properties. However, challenges such as inadequate electrical conductivity, elevated skin impedance, unreliable adhesion in moist conditions, and performance decline from dehydration have significantly restricted the efficacy and applicability of hydrogel-based electrodes. In this thesis, we report a high-performance hydrogel epidermal electrode patch for …

Review Of The Potential Use Of Poly (Lactic-Co-Glycolic Acid) As Scaffolds In Bone Tissue Recovery, Kushendarsyah Saptaji, Asriyanti Asriyanti, Nisa Khoiriyah, Laely Muryanti, Iwan Setiawan

Makara Journal of Science

Scaffolds are used as temporary tissue in the human body to expedite healing. Biocompatible materials play a vital role in the field of tissue engineering. Therefore, they can be used to reduce human pain as soon as possible. Polymeric materials are widely used to replicate bone tissue. Poly(lactic-co-glycolic acid) (PLGA) is a potential material for bone tissue scaffolds because of its superior properties, including compatibility with the human body. Accordingly, adding hydroxyapatite and introducing different fabrication methods can enable the production of PLGA scaffolds with good abilities to help cells grow, expand, differentiate, and proliferate. The paper reviews the current …

4d Epr Oximetry Imaging For 4d Bioprinting And Tissue Engineering, Sajad Sarvari

Graduate Theses, Dissertations, and Problem Reports (ETD)

Bioprinting, akin to 3D printing, employs cell-laden hydrogels such as GelMA (Gelatine Methacrylate) and Alginate instead of plastic or resin to create biological structures. The printing process followed by subsequent tissue maturation is known as 4D bioprinting, where the fourth dimension is time. Ensuring adequate and consistent oxygen, O2, supply within 3D bioprint volume over the entire maturation period process is crucial, as even transient hypoxia can impact cellular behavior and phenotypes. However, printing of fully developed vasculature remains an unresolved technical challenge. Several approaches to chemically (peroxides) or biologically (photosynthesis) generate oxygen during bioprint maturation have been proposed. However, …

Muscle-Nerve Signaling And Its Role In Myogenesis, Synaptogenesis, And Regeneration, James T. Redden

Theses and Dissertations

Despite only comprising 0.1% of the myofiber surface area, a healthy motor endplate is densely packed with acetylcholine receptors (AChRs) responsible for mediating activity between the connected motor neuron and skeletal muscle via the neurotransmitter, acetylcholine. Loss of the endplate, known as fragmentation, is caused by car crashes, deep lacerations, and other traumatic injuries to the innervating nerve or direct injuries to the limb muscle(s) with intramuscular denervation as a common comorbidity. In both cases, endplate fragmentation begins within a week of injury proceeding muscle atrophy causing decreased mobility, paralysis, and quality of life. Endplate fragmentation of intact muscle fibers …

Matrix Stiffness Sensing By Nascent Adhesions And The Role Of Riam In Adhesion Assembly, Nikhil Mittal

Dissertations, Master's Theses and Master's Reports

Mechanical stiffness of the extracellular matrix (ECM) impacts many cellular functions such as proliferation, migration, and differentiation. ECM stiffness is sensed by a cell via integrin-based focal adhesions (FAs) by changing conformation and biochemical activities of molecules within FAs by the exchange of the force between the ECM and filamentous actin (F-actin). Cells in turn respond to this stiffness by generating traction force that plays an important role in many biological events such as tissue morphogenesis, stem cell differentiation, wound healing, and cancer cell metastasis. The stiffness of the extracellular matrix induces differential tension within integrin-based adhesions. Understanding stiffness sensing …

Air-Jet Bioprinting Of Stem Cell-Encapsulated Alginate Micro-Droplets For Organoid Biomanufacturing, Mirabella B. Stump

Electronic Theses and Dissertations

Biomanufactured 3D-organoids show promise for modeling and treating various conditions, particularly insulin-dependent diabetes mellitus (type-1 diabetes). Pancreatic islet organoids serve as sustainable sources of insulin-producing β-cells, potentially restoring insulin regulation in patients and providing a long-term solution for diabetes. Hydrogel droplet printing is an emerging technique in regenerative medicine due to its advantageous tunability and biocompatibility; however, challenges of consistency, quality control, and scalability persist. To address these issues, we developed a novel air-jetting based droplet bioprinting system for the generation of monodispersed alginate micro-droplets. The objective of this project was to incorporate human induced pluripotent stem cells (hiPSCs) into …

Engineering Next-Generation Cardiovascular Therapies, Ryan Walker Barrs

All Dissertations

Cardiovascular diseases are the leading cause of death worldwide. Heart disease, in particular, accounted for 1 in every 5 deaths in the United States in 2021, representing a substantial public health burden that will require more effective treatment options to alleviate. Heart transplant surgery is currently the only option to completely restore cardiac function, but many patients die while waiting for a transplant due to a longstanding organ donor shortage. Thus, there is a dire need for accessible treatment options that can repair damaged hearts. Recent advances in tissue engineering and regenerative medicine have accelerated the development of therapies for …

Development Of Air-Jetting System For Bioprinting Of Alginate Micro-Droplets, Nathan Lingenfelter

Electronic Theses and Dissertations

Transplantation of organoids has been demonstrated to be a promising cure to many diseases including Type-1 diabetes. However, achieving consistent and robust derivations of mature organoids from human pluripotent stem cells (hPSCs) is challenging. Cellular mechano-transduction, where mechanical stimuli is sensed and converted to biochemical signaling, has been proposed to overcome this challenge. This pathway relies on encapsulating hPSCs in a small volume of a biomaterial such as alginate, which has been widely used as cell encapsulation materials due to its biocompatibility and selective permeability. In this project, we focused on developing an air-jetting based technique to generate small and …

Prevention And Reversal Of Elastin-Associated And Phosphate-Dependent Arterial Calcification Using Targeted Nanotherapeutics In Pre-Clinical Models, Fatema Tuj Zohora

All Dissertations

Vascular calcification can be life-threatening, involving calcium phosphate crystal deposits in the blood vessels. The calcification in the intimal layer of the arterial wall is usually associated with atherosclerotic plaque build-up that, in the advanced stage, harbors ‘dispersed’ and ‘spotty’ deposits of calcium phosphate crystals in the necrotic core of the plaque. In contrast, medial arterial calcification (MAC) can form independently of atherosclerosis and appears as ‘Railroad-like’ calcific deposits along degraded elastin lamellae in the medial layer of arteries. The mechanisms of such elastin-associated medial arterial calcification and potential therapies are the key concerns of this dissertation. MAC is common …

In Vitro And In Vivo Diabetic Models For Assessment Of Tissue Engineered Vascular Grafts, Juan Carlos Carrillo Garcia

All Dissertations

Diabetes has become one of the leading causes of lower-limb loss worldwide. Every 30 seconds, a person loses a limb due to diabetic-related vascular complications. About one-third of patients needing lower-limb bypass surgery have debilitated autologous vessels unsuitable for use, and no other good long-term options are available. These detrimental effects on the vasculature are caused mainly by the hyperglycemic and hyperlipidemic conditions derived from diabetes. Under these conditions, an increase in advanced glycation end products (AGEs) and reactive oxygen species leads to irreversible crosslinks of extracellular matrix proteins, accelerating vascular pathology through vascular stiffening, endothelial dysfunction, inflammation, atherosclerosis, fibrosis, …

Study Of The Stability Of Heparin/Collagen Layer-By-Layer Coatings, Hector M. Apodaca Reyes

Chemical Engineering Undergraduate Honors Theses

Pairing heparin with collagen-based medical implants has opened a whole new area of research for enhancing the desired effect of current implants. In fact, heparin (HEP) and collagen (COL) layer-by-layer (LbL) coatings have shown impressive results in forming polyelectrolyte multilayers. It has been already seen on skin grafts, nerve guide conduits (NGCs), and drug delivery devices yielding promising results. Due to being a simple, cost-efficient, and versatile option to fabricate thin biomimetic films, this self-assembly technique is one of the most effective methods to immobilize extracellular matrix (collagen and heparin) onto medical devices and implants. Even though previous studies have …

A Magneto-Rheological Platform To Dynamically Control Afterload In Engineered Micro Heart Muscles, David Schuftan

McKelvey School of Engineering Graduate Student Theses & Dissertations

Cardiovascular disease is the leading cause of death is the United States, accounting for nearly 1 in 5 deaths. Many types of cardiovascular disease are linked to the mechanical forces placed on the heart. However, how these mechanical forces exactly affect the cellular biology of the heart is not well defined. In vitro models using cardiomyocytes derived from human induced pluripotent stem cells enable researchers to develop medium throughput systems to study cardiac mechanobiology at the cellular level. Previous models have been developed to enable the study of mechanical forces such as cardiac afterload. However, most of these models require …

Polymeric Biomaterials Approaches For Engineering The In Vitro Cellular Microenvironment For Mscs, Mahsa Letter-Mahsa Haseli

Graduate Theses and Dissertations

Cell therapy is a technology that relies on replacing diseased or dysfunctional cells with healthy functioning ones. One of the cells used for such advanced therapies are stem cells, owing to their ability to differentiate into specific cells required for repairing damaged or defective tissues or cells. The majority of cell-based products are intended to transiently persist in the patient, secreting factors which then allow the patient’s body to heal; in these products, the cells are subsequently eliminated from the body. Furthermore, unique manufacturing platforms, in addition to novel commercialization strategies, will be required to create a successful, sustainable cell …

Regenerative Medicine For Tendon/Ligament Injuries: De Novo Equine Tendon/Ligament Neotissue Generation And Application, Takashi Taguchi

LSU Doctoral Dissertations

Tendon and ligament injuries are debilitating conditions across species. Poor regenerative capacities of these tissues limit restoration of original functions. The first study evaluated the effect of cellular administration on tendon/ligament injuries in horses using meta-analysis. The cellular administration was effective in restoring ultrasonographic echogenicity and increasing vascularity during early phase of healing. Additionally, it improved microstructural organization of healed tissue in terms of cellularity and fiber alignment. However, the study did not support its use for increasing rate of return to performance, expression/deposition of tendon-specific genes/proteins, or mechanical properties.

The findings led to the second study that engineered implantable …