Biomaterials Commons^™

Effect Of Reinforcement Thickness And Content On The Properties Of Compressed Earth Blocks, Salah Eddine Mokeddem, Abdelmadjid Hamouine, Rabia Abdeldjebar, Atef Hamaidi

Journal of Sustainable Construction Materials and Technologies

This study explores the mechanical, hygroscopic, and thermal behavior of stabilized and unstabilized compressed earth blocks (CEB) by incorporating date palm wood chips (DPWC) as a natural fiber additive. The investigation covers a range of DPWC thicknesses (1 mm, 2 mm, 3 mm) and content variations (0% to 1% by weight), focusing on the interaction between the bio-based reinforcement and the stabilized soil matrix, which is stabilized with 10% white Portland cement. The mixtures were compressed at a pressure of 5 MPa using a hydraulic press, providing a detailed examination of how these parameters impact the structural integrity and functional …

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 …

Opmed Seal: Engineering A Rapid-Response Biodegradable Device For Hemorrhage Control And Infection Prevention In Abdominal Trauma, Paula M. Cabrera, Wesley Stephen Murphy

Honors Theses

Abdominal gunshot wounds are amongst the deadliest injuries encountered in combat and remote emergency settings. For military medics and first responders, the challenge lies in controlling internal bleeding and preventing infection before patients can reach surgical care-often within a narrow window of time known as the “golden hour”. Currently available field treatments are either too slow, not designed for internal wounds, or fail to provide antimicrobial protection. To address this gap, our team developed OpMed Seal: a compact, dual-syringe delivery system that deploys a biodegradable, antibiotic-infused hydrogel directly into abdominal injuries. The system is designed for rapid hemorrhage control, localized …

Analysis Of The Mechanical, Microstructural, And Biocompatibility Properties Of Novel Magnesium-Based Hybrid Nanocomposite Materials For Orthopedic Applications, Thomas H. Mcgehee

Biomedical Engineering Undergraduate Honors Theses

Bone fractures and complete joint replacements are becoming more common, primarily because of accidents and age-related issues. Conventional solutions to treat these orthopedic injuries involve inert metal alloys to correct bone fractures until the healing process is complete, where a secondary revision surgery is then required to remove the implant. Issues regularly associated with these solutions include stress shielding, bone resorption, infection, inflammation, and implant loosening. Magnesium (Mg)-based nanocomposites offer promising potential as an alternative to commonly used metal alloys because of their favorable mechanical properties and biocompatibility. A particularly advantageous property of Mg is its natural biodegradation in vivo, …

Fabrication And In Vitro Biocompatibility Assessment Of Composite-Coated Magnesium Materials, Bryce Williams

Biomedical Engineering Undergraduate Honors Theses

This study provides a comparative assessment of the corrosion, morphology, and biological properties of four of the most promising coating methods for magnesium in biomedical applications, namely micro-arc oxidation (MAO), graphene oxide (GO)-containing MAO coating, MAO/sol-gel composite coating, and MAO/polycaprolactone (PCL) polymer dip coating approaches. Despite the abundance of research focused on these promising approaches, there is a notable lack of comparative studies evaluating their properties. To this end, the investigated composite coatings are ZK60+MAO, ZK60+MAO/GO, ZK60+MAO/Sol-gel, and ZK60+MAO/PCL composite coating. Several tests were used to assess various properties of the prepared groups such as in vitro corrosion characteristics, surface …

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 …

The Effect Of A Peptide Targeting Ligand On Transfection Efficiency Of Polymeric Nanoparticles To Dendritic Cells, Anthony Radka

Honors Theses

Autoimmune diseases affect approximately 5-8% of the global population, leading to chronic symptoms, long-term treatment, and reduced quality of life. Current therapies primarily rely on lifelong administration of immunosuppressants, which are associated with severe side effects and heightened susceptibility to infections. This has spurred interest in cellular therapies that manipulate dendritic cells (DCs) effectively and can selectively treat these diseases. This work aims to improve the efficacy of dendritic cell-based therapies using cationic polymers that can electrostatically complex with nucleic acids, forming nanoparticles referred to as polyplexes, that can deliver therapeutic nucleic acid cargo. These particles are a favorable alternative …

Deciphering And Translating Bioinspired Structures For Engineering Materials Design Via Computational Modeling And Machine Learning, Zhangke Yang

All Dissertations

Nature has evolved extraordinary structural materials—such as nacre, bone, and the mantis shrimp’s dactyl club—that achieve remarkable combinations of strength, toughness, and impact resistance. These properties arise from sophisticated synergies between structure and composition. Inspired by these biological systems, this dissertation presents a comprehensive investigation into bioinspired materials, uncovering fundamental mechanisms and providing guidance on designing materials with superior mechanical properties.

This dissertation begins by examining the "brick-and-mortar" structure of nacre, which informs the design of layered polymer-graphene nanocomposite films. Using coarse-grained molecular dynamics simulations, I elucidate mechanisms of dynamic wave propagation and energy dissipation in these systems, providing critical …

Design And Evaluation Of Antibody-Conjugated Microneedle Patch For Early Mrsa Biomarker Detection, Kylee Marie Pop, Alexis Richie, Nicholas Jenkins, Andrew Holmes

Honors Theses

Post-operative orthopedic surgical site infections (SSIs), specifically those caused by methicillin resistant Staphylococcus aureus (MRSA), present a significant clinical challenge due to delayed detection, increased morbidity, and current rising healthcare costs. Early detection of infection remains limited due to the current methods of diagnosis, which consist of observation of the surgical site and laboratory infrastructure for conformation of infection. To combat these issues, my team and I have designed and evaluated a minimally invasive microneedle diagnostic patch that continuously monitors for the presence of MRSA-associated biomarker PBP2a in interstitial fluids around surgical site incisions. Upon antigen detection, a colorimetric response …

Mechanistic Investigation Of Ring-Opening Polymerization Of Polycaprolactone Using Tin(Ii) Catalysts: Ligand Effects And Biomedical Applications, Eva-Larue M. Barber

Honors Scholar Theses

This research explores the mechanistic aspects of ring-opening polymerization (ROP) of ε-caprolactone (CL) to produce polycaprolactone (PCL), a biodegradable polymer widely used in biomedical applications. The study investigates how light exposure and catalyst concentration influence polymerization efficiency, using tin(II) 2-ethylhexanoate [Sn(Oct)₂] as the catalyst in a non-polar toluene solvent at 90 °C. Reactions were conducted under either ambient light or black light bulb (BLB) illumination, with monomer-to-catalyst ratios of 1:1 and 200:1.

Proton nuclear magnetic resonance (¹H NMR) spectroscopy was used to analyze conversion efficiency by tracking the disappearance of monomer signals and appearance of characteristic PCL peaks. Results revealed …

Development Of Rolipram Loaded Pgp Nanoparticles For Spinal Cord Injury Repair, Zhen Liao

All Dissertations

Spinal cord injury (SCI) leads to devastating neurological deficits due to primary mechanical damage and secondary injury mechanisms, including inflammation, oxidative stress, excitotoxicity, and inhibitory scarring, which collectively impede neural regeneration. One key aspect of SCI pathology is a significant reduction in cyclic adenosine monophosphate (cAMP) levels, primarily due to increased phosphodiesterase (PDE 4) activity. As a ubiquitous second messenger, cAMP regulates key signaling pathways, including protein kinase A (PKA) / cAMP response element-binding protein (CREB) and exchange protein activated by cAMP 2 (EPAC2). Therefore, restoring/increasing cAMP level is one of the major therapeutic strategies to reduce neurotrauma and restore …

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, …

Optimizing Hydrogel Performance Composed Of Japanese Pagoda Tree Extract Loaded-Gelatin-Sodium Alginate-Polyethylene Oxide For Biomedical Applications: Influence Incorporated Calcium-Based Metal Organic Frameworks And Zinc Oxide Nps, Samar A. Salim

Nanotechnology Research Centre

Gelatin/sodium alginate/polyethylene oxide hydrogel was synthesized by self-gelation method and utilized to achieve enhanced mechanical strength. Japanese pagoda, tree extracts rich in flavonoids and isoflavonoids was incorporated to enhance tissue repair along with ZnO-NPs to provide the hydrogel with necessary antimicrobial and other desirable biological properties. The inclusion of Ca-BDC MOF enhanced hydrogel matrix by providing more surface area and the presence of calcium ion needed for tissue regeneration. Results revealed that composite hydrogel displayed suitable gelation time and swelling rate that was further improved by incorporating the plant extract, ZnO-NPs, and Ca-BDC MOF. The efficacy of the tested formulations …

Evervital Patch: The Design And Development Of A Continuous Cardiac Monitoring Device For Post-Operative, In-Hospital Patients, Abigail Moeller, Jonathan Seid

Honors Theses

In the United States, due to the increasing prevalence of cardiovascular disease, over 900,000 cardiac surgeries are performed annually, with projections exceeding 1.3 million by 2029. Many post-surgical patients require continuous in-hospital cardiac monitoring, which is typically conducted using electrocardiograms (EKGs). However, traditional EKG systems such as bedside cardiac monitors and cardiac telemetry monitors rely on wired leads that can easily tangle, degrade signal quality, and require frequent readjustments or replacements due to wire breakage, and for the patient, this can cause discomfort from prolonged use. To overcome these challenges, our company, CardioSync, aims to develop a wireless cardiac monitoring …

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 …

Comparison Of Milling Cutting Forces In Synthetic And Biological Cancellous Bone, Matthew Christopher Hartwell

Masters Theses

In many orthopedic and dental interventions, the cutting and removal of bone is necessary. Therefore, it is of the utmost importance that the tools used during these procedures are designed and tested with biological bone or a bone surrogate material that machines the same way as biological bone. To avoid the cost, hazard, and inconsistency of biological cadaveric bone or animal models, many biological engineering firms use bone surrogate material made of glass fiber filled epoxy and polyurethane foam. Although these materials may mimic the elongation of cortical and cancellous bone, respectively, the match of machinability of the bone is …

Enhancing The Mechanical Properties Of Sla 3d-Printed Bio-Resin From Linseed Oil Using Cellulose And Lignin Biopolymers, Chukwunonso A. Ikedionu

College of Graduate Studies: Theses & Dissertations

Abstract

This research explores the development of bio resin from linseed oil by the process of epoxidation and acrylation to produce acrylated epoxidized linseed oil (AELO). Lignin and cellulose biopolymers were added as reinforcement at varying weight fractions of 1 wt.%, 2.5 wt.%, and 5 wt.%, and their mechanical performance was compared against pure AELO. The formulations were printed using an Elegoo SLA 3D printer to create standardized test specimens like tensile bars, compression cylinders, and hardness blocks, which were all prepared according to the ASTM testing standard.

The results indicate that reinforcement effects depend on both filler type and …

Optimization Of Small-Scale Bioreactors For Increased Pdna Production And Yield, Laura M. Hills

Honors Theses and Capstones

No abstract provided.

Synthesis Of Bio-Orthogonal Hydrogels For 3d Cell Culture Via Penicillamine Β-Thiolactone-Mediated Native Chemical Ligation, Kaelin E. Marshall, Matthew E. Currier, Nathan J. Oldenhuis

Honors Theses and Capstones

Many hydrogel systems designed to mimic the extracellular matrix (ECM) employ thiol-based chemistries with undesirable functional groups, including vinyl sulfones and methacrylates. In downstream applications, any unreacted functional groups are problematic and render hydrogels non-viable for human use. Here, we introduce modifications to the Native Chemical Ligation (NCL) mechanism, exploring the elimination of cytotoxic byproducts and increased reaction rate by using a β-thiolactone. The inclusion of the β-thiolactone results in retention of the thiol within the gel, as well as enhanced kinetics due to the thermodynamic favorability of the ring opening and amide formation. We achieved this by functionalizing 4-arm …

Magnetic Heating Efficiency Of Magnetite Nanoparticles: Dependence On Size And Alternating Magnetic Field, Sarah E. Kubican

Theses and Dissertations--Biomedical Engineering

Magnetic heating mediated by magnetic iron oxide nanoparticles (MION) has several clinical applications including cancer thermal therapy, tissue thawing for organ preservation, and magnetogenetics. However, current models of magnetic heating, including the widely used linear response theory, inadequately predict MION heating efficiency. An experimental study covering alternating magnetic field (AMF) strengths and frequencies ranging from 3.98 – 27.85 kA/m and 103.6 – 984.1 kHz, respectively, with a range of MION core diameters 9.5- 30.3 nm was conducted to elucidate the relationships between these AMF parameters and MION sizes and the resulting heating efficiencies. Heating efficiency was found to increase approximately …

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 …

Application-Driven Materials Development Of Solid-State Conductive Composites Of Ultra-High Molecular Weight Polyethylene, Peder Solberg

Dartmouth College Ph.D Dissertations

Ultra-high molecular weight polyethylene (UHMWPE) is a linear long chain homopolymer valued for its toughness, wear resistance, and chemical inertness. In the medical field, these properties make it the material of choice for bearing surfaces despite recognized tradeoffs between wear resistance, toughness, and oxidation resistance. Electrically conductive composites of UHMWPE show promise to enable new types of smart and active load-bearing implants in a future of personalized medicine, if beneficial properties can be maintained with the addition of solid-state additives.

Clinical need-finding conducted through Dartmouth’s Training Program in Surgical Innovation revealed several potential applications for conductive, load-bearing polymers. These include: …

A Pyrrole Modified 3,4-Propylenedioxythiophene Conjugated Polymer As Hole Transport Layer For Efficient And Stable Perovskite Solar Cells, Yuanhao Tang, Ke Ma, Wenhao Shao, Yoon Ho Lee, Ashkan Abtahi, Jiaonan Sun, Hanjun Yang, Aidan H. Coffey, Harindi R. Atapattu, Mustafa Ahmed, Qixuan Hu, Wenzhan Xu, Raunak Dani, Limei Wang, Chenhui Zhu, Kenneth R. Graham, Jianguo Mei, Letian Dou

Chemical and Materials Engineering Faculty Publications

Despite the outstanding electric properties and cost-effectiveness of poly- (3,4-ethylenedioxythiophene) (PEDOT) and its derivatives, their performance as hole transport layer (HTL) materials in conventional perovskite solar cells (PSCs) has lagged behind that of widely used spirobifluorene-based molecules or poly(triaryl amine). This gap is mainly from their poor solubility and energy alignment mismatch. In this work, the design and synthesis of a pyrrole-modified HTL (PPr) based on 3,4-propylenedioxythiophene (ProDOT) are presented for efficient and stable PSCs. As a result of the superior defects passivation ability, excellent contact with perovskite, enhanced hole extraction, and high hydrophobicity, the unencapsulated PPr-based PSCs showed the …

Comparative Analysis Of Electrode Encapsulation Reliability: Planar Vs. Thermoformed Interdigitated Neural Electrodes In Biomedical Engineering, Tatum Peyerl

Graduate Theses, Dissertations, and Problem Reports (ETD)

Durable dielectric encapsulation is crucial for the long-term function of implantable neural electrodes; however, the reliability of curved, thermoformed coatings remains underexplored. This study addresses that gap by comparing planar (non-thermoformed) and thermoformed interdigitated neural electrodes (IDEs) encapsulated in Polyimide-2611. Both device types underwent accelerated in vitro aging in phosphate‑buffered saline (PBS) at 67 °C for approximately 91 days, simulating two years of physiological exposure. Post-accelerated aging evaluation included electrochemical impedance spectroscopy (EIS) from 0.1 Hz to 100 kHz to monitor moisture‑induced leakage, and high‑voltage breakdown testing under saline immersion to assess dielectric strength. After aging, all electrodes maintained impedance …

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 …

Delivery Method For Dissolvable Staples, Brian Nguyen, Colleen Kroah, Bethany Fogle, Sean Brown

Williams Honors College, Honors Research Projects

Surgical staples play a vital role in modern medicine by enabling efficient wound closure and tissue repair. However, traditional metal staples often require removal, increasing patient discomfort and the risk of infection. Dissolvable staples offer a promising alternative, eliminating the need for removal while maintaining secure wound closure. Despite their potential, current delivery systems for dissolvable staples face significant challenges, including inconsistent deployment, lack of precision, and inadequate integration with surgical workflows.

Developing an optimized delivery system is critical to maximizing the benefits of dissolvable staples. Such a system must ensure reliable performance, precision, and ease of use while maintaining …

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 …

Synthesis And Characterization Of Multifunctional Cerium Oxide Containing Nanoparticles For Biomedical Applications, Ishaan Patel

Honors Undergraduate Theses

This study presents the synthesis and comprehensive characterization of a novel core-shell nanoparticle composed of a maghemite (γ-Fe₂O₃) core and a europium-doped cerium oxide (EuCNP) shell, developed for potential use in cancer theranostics. Using a co-precipitation method, Fe₂O₃–EuCNP core-shell nanoparticles were synthesized and compared against control samples of CNPs, EuCNPs, and Fe₂O₃. A variety of characterization techniques, including UV-Vis spectroscopy, fluorescence spectroscopy, TEM, XRD, XPS, DLS, TGA, and DSC confirmed the successful synthesis of core-shell architecture and europium doping. Moreover, Fe₂O₃–EuCNPs demonstrating strong colloidal …

Investigation Using Single Point Incremental Forming (Spif) To Fabricate Patient-Specific, Titanium Orbital Floor Implants, Elizabeth M. Mamros, Lauren E. Blaha Md, Christian A. Kauffman Md

Faculty Conference Papers and Presentations

The floor of the human orbit is composed of thin bone that is prone to traumatic fracture. This leads to a loss of support for the eye, which can cause vision changes. Therefore, fractures may need surgical reconstruction using a thin, sheet-like implant. Titanium implants are available off-the-shelf in standard sizes, but fitting to each patient’s unique anatomy requires surgeons to cut, file, and bend these plates. This can be time-consuming and imprecise. To both save time and ensure a perfect fit for the patient, a custom plate can be created prior to surgery. This investigation focuses on single-point incremental …