Biomaterials Commons^™

Crevice Corrosion Mechanisms Of Cocrmo Alloys In Orthopedic Implants: Retrieval Analysis, Nano-Tribocorrosion And Cellular Responses, Hwaran Lee

All Dissertations

Mechanically assisted corrosion and non-mechanically (chemically) driven corrosion in modular junctions of orthopedic implants using cobalt-chromium-molybdenum (CoCrMo) alloys remain clinical concerns and may contribute to implant failure. The underlying corrosion mechanisms are not yet fully understood, leaving a critical research gap. We hypothesized that corrosion in modular junctions may be driven by aggressive local environments, including fretting, metal ion release (cobalt ion, Co²⁺), low pH and reactive oxygen species (ROS). This dissertation aims to (1) analyze corrosion modes and potential causes in modular junctions; (2) identify chemically driven corrosion modes on CoCrMo alloys using simulated inflammatory modular taper …

Development And Characterization Of Pmma/Pvp Nanofiber-Loaded Bioactive Agents With Enhanced Breast Cancer Activity, Samar A. Salim, The British University In Egypt, Esraa Abdelazim, Marwa Abdel Aleem

Nanotechnology Research Centre

Breast cancer remains a leading cause of cancer-related mortality globally, driving the need for novel effective and less toxic therapeutic agents. This study explores the synthesis and characterization of bioactive compounds: 1-(4-methoxyphenyl)-N- (p-tolyl)methanimine (MPTI), N-(4-methylphenyl)benzamide (MPB), and 4-methyl-N-(p-tolyl)benzenesulfonamide (MTS), and their incorporation into a PMMA/PVP polymer matrix for potential anticancer applications. Morphological analysis of the PMMA/PVP-loaded agents via SEM depicts structural modifications in the PMMA/PVP nanofibrous matrix upon incorporation of the bioactive agents. The FTIR analysis of the synthesized compounds before and after loading into the 7PMMA:3PVP nanofibers reveals successful incorporation of MPTI, MPB, and MTS, with characteristic absorption bands …

Harnessing Environmentally Healthy Approaches For Plastic Degradation: A Review And Future Perspectives, Marc Chojnacki

Beyond: Undergraduate Research Journal

In the face of escalating plastic pollution, innovative degradation strategies, such as enzymatic degradation, smokeless incineration technology, and biodegradable plastics, are gaining traction. This paper collates comprehensive research on these methods, assessing their environmental impact and operational feasibility. A special focus is placed on the role of technology and its capacity to spark advancements in these degradation strategies as well as to draw on specific research to understand the economic implications of these methods. At the core of this study is the exploration of potential new, inventive degradation methodologies. Through examining methods of green plastic degradation, the study aims to …

Characterization Of Lactobacilli-Containing Catheter Segments Developed By Using Selective Laser Sintered Mold., Caden Maners

Master of Engineering Theses

Catheter-associated urinary tract infections (CAUTIs) are a major healthcare burden with current prevention strategies offering limited success. This study presents a novel, self-coating biomaterial approach using a silicone-based bioink embedded with thermally sensitive probiotic strains (L. crispatus, L. rhamnosus, and L. reuteri). Catheter segments were fabricated via bio-injection molding using 3D-printed CAD molds. These Lactobacilli, selected for their probiotic and antimicrobial potential, serve as a non- antibiotic strategy to reduce infection risk. These segments were evaluated for mechanical strength (Shore A hardness), thermal stability (TGA/DSC), porosity and bacterial presence (SEM), biofilm formation (crystal-violet assay), as well as mass retention in …

A Wearable-Based Approach To Spinal Posture Tracking And Assessment, Sydney Marie Sherman, Noah Jeffery

Biomedical Engineering: Graduate Reports and Projects

This paper describes the design, manufacturing, and testing of a novel spinal posture tracking wearable device with embedded sensors. Currently on the market, most of the spinal posture tracking devices only focus on one segment of the spine and therefore do not track the entirety of human posture. The objective for this project was to create a wearable device in the form of a “smart shirt” that offers insights into posture trends throughout the day by tracking the entire spine. To begin the project, multiple designs were developed for the sensor array and wearable materials. These concepts were compared against …

The Utilization Of Basic Oxygen Furnace Slag As Fine Aggregates In Concrete: Physical, Mechanical, And Durability Properties, Hakan Ozkan

Journal of Sustainable Construction Materials and Technologies

This study examines the feasibility of using basic oxygen furnace slag (BOFS) as an alternative to fine crushed limestone aggregate in concrete. BOFS is sourced from two steel production facilities in Türkiye, designated as I-BOFS and E-BOFS. The experimental results showed that as the E-BOFS aggregate replacement ratio increased, the water-to-cement (w/c) ratio increased to maintain the target workability. The concrete mixtures incorporating E-BOFS exhibited consistent reductions in the compressive strength with an increase in the BOFS ratio. At the same time, I-BOFS maintained higher compressive strength, with only minor losses up to 80% of the substitution ratio. Flexural strength …

Development Of A Self-Cured Alkali-Activated Mortar, Kübra Ekiz Barış

Journal of Sustainable Construction Materials and Technologies

Alkali-activated mortars (AAM) can be produced with self-curing (SC), which supplies internal moisture to accelerate alkaline-activation reactions. The aim of using SC is to make AAMs with an early-age strength without any additional curing energy consumption and higher CO2 emissions, and to obtain in-situ practical advantages that enable the large-scale application of AAMs. The previous study produced natural pozzolan-based AAMs by applying energy-intensive heat (HC), microwave (MWC), and hybrid (HC+MWC) curing. This study investigates alternative curing regimes that reduce production energy without compromising material properties. The impacts of air curing (AC), water curing (WC), and SC on the properties were …

Naoh Molarity Effect On Mechanical And Hydrochloric Acid Resistance Of Geopolymer Mortar Based On Slag, Mahmoud Ziada, Zahraa Mohammed Kamil Al-Mayali

Journal of Sustainable Construction Materials and Technologies

The present research investigates the influence of different sodium hydroxide (NaOH) molarities on the mechanical characteristics and hydrochloric acid (HCl) resistance of geopolymer grouts manufactured from ground granulated blast-furnace slag (GGBS). Geopolymer mortars have attracted interest as sustainable substitutes for traditional cementitious materials due to their advantageous environmental effects and enhanced durability features. This study involved the fabrication of geopolymer mortar specimens by altering the NaOH molarity (M) from 6 M to 14 M. The mechanical and physical qualities were assessed using compressive strength, capillary water absorption, flexural strength, slump flow, and ultrasonic pulse velocity (UPV) tests. Subsequently, the geopolymer …

Effect Of Expanded Perlite And Exfoliated Vermiculite Aggregate Additives On Water Vapor Permeability Performance Of Cement-Based Lightweight Mortars, Lütfullah Gündüz, Şevket Onur Kalkan

Journal of Sustainable Construction Materials and Technologies

Vapor diffusion is the movement of water vapor molecules through porous materials such as wood, insulation products, and lightweight wall elements due to differences in vapor pressure. Vapor retarders are used to control vapor diffusion through wall sections and surfaces. All building materials provide some resistance to vapor diffusion, and the amount of resistance varies depending on the material's properties. These properties can vary with relative humidity and moisture content, age, temperature, and other factors. Vapor resistance is usually expressed using the inverse term of ``vapor permeability,'' which is the relative ease of vapor diffusion through a material. Water vapor …

Rubber-Modified Self-Compacting Mortar: Evaluating Setting Time And Strength Development, Navvar Makansi, Süleyman Ipek, Erhan Güneyisi

Journal of Sustainable Construction Materials and Technologies

The influence of using crumb rubber (CR) obtained from the second scraping of used tires as fine aggregate in manufacturing self-compacting mortar (SCM) was investigated experimentally in this study. To explore this, natural fine aggregate in SCM mixes was partially replaced with CR at levels ranging from 5% to 25% by total fine aggregate volume. Two mix series, one with a total binder of 500 kg/m3 and the other with a 540 kg/m3 binder, were designed at water-to-binder ratios of 0.40 and 0.33. Ordinary Portland cement (80% by weight) and fly ash (20% by weight) were used to manufacture mortars. …

Smart Traffic Management At Intersections, Gezim Hoxha, Piotr Gorzelanczyk, Rame Likaj, Shaban Thaqi, Flori Cikaqi

Journal of Sustainable Construction Materials and Technologies

Effective traffic control methods, whether at intersections or other nodes within the road network, play a critical role in ensuring traffic quality and safety. An inappropriate choice of traffic control techniques or poorly optimized light signal programming at intersections often leads to unsatisfactory service levels. This study specifically addresses the issues related to intersections controlled by traffic lights. It aims to identify the key factors influencing the regulation and programming of traffic lights, with a focus on using different microcontrollers, particularly the Raspberry Pi. The primary objective of this research is to develop a methodology and an adapted programming approach …

Identification Of Barriers And Drivers In The Adoption Of Sustainable Construction Practices In The Turkish Construction Industry: Exploratory Factor Analysis, Tülay Çivici, Mustafa Serhan Ünlütürk

Journal of Sustainable Construction Materials and Technologies

Although the importance of sustainability in the construction industry has been emphasised by many researchers and endorsed by many authorities, it is clear that the practices in the industry still need to be improved. The primary issue for adopting sustainable practices in the construction industry is identifying the barriers and drivers. For this reason, the study analysed the literature to identify the critical barriers and incentives for adopting sustainable practices in the construction industry. In light of the information from the literature, the necessary barriers and motivators in adopting sustainable practices in the construction industry were determined, and a questionnaire …

Synergistic Effect Of Alccofine As Partial Replacement Of Cement And M-Sand As Sand Substitution In Concrete For The Assessment Of Mechanical And Microstructural Properties, Yellinedi Madhavi, R.S. Ravichandran, J. Saravanan, N. Venkatasairam Kumar

Journal of Sustainable Construction Materials and Technologies

Using supplementary cementitious materials (SCMs) and traditional binder mass has revolutionized concrete production technology in the building industry. This study examines how Alcofine-1203 affects the microstructure and mechanical characteristics of concrete. The mechanical qualities of the mixtures were evaluated using six different mixes prepared for each M25 and M40 Grade. In the proposed mixes, cement is substituted with alccofine at 0 to 25% and M-Sand as fine aggregate. The Compressive strength and ultrasonic pulse velocity were assessed after 3, 7, 14, 28, 56, and 90 days of curing, and split tensile strength and flexure strength were evaluated after 28 and …

Sustainable Modification Of Stone Column Technique With Polyethylene Terephthalate (Pet) Plastic For Strengthening The Expansive Clay, Ng Jun Shen, Muzamir Hasan

Journal of Sustainable Construction Materials and Technologies

This research investigated the modification of stone column application by the association of PET plastic as a coarse aggregate material for sustainable material replacement. Clay soil improvement with a granular material fabricated column substantially affected its soil-bearing capacity. Subsequently, it avoided severe problems such as soil settlement and structural instability. Previous studies have mentioned the function and alteration of stone columns using materials like bottom ash and fly ash. Still, no attention has been paid to the utilization of PET plastic for this area. This study examined the feasibility and reliability of materials, PET plastic, and kaolin clay S300 before …

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 …