Matching Items (326)
Description
Enhancing the expression levels of Fabs (antigen-binding antibody fragments) in Escherichia coli is a difficult field that has a variety of potential exciting implications. The field has grown substantially in the past twenty years. The main area of difficulty is facilitating the entry of the antibody fragments into the periplasm of E. Coli, where the antibody fragments can be successfully expressed. Entry into the periplasm is difficult for antibody fragments due to their inability to fold in any other section besides the periplasm. Therefore it is necessary for the antibody to enter the periplasm in an unfolded state. Background research was done into inspecting the three primary methods of periplasmic entry: the Sec-dependent pathway, the SRP-dependent pathway (signal recognition particle) and the TAT-dependent pathway (twin arginine translocase). The Sec-dependent and SRP-dependent pathways were deemed more viable for expressing antibodies due to their ability to transfer an unfolded protein into the periplasm, which the TAT-dependent pathway cannot do. Academic research showed that the Sec-dependent and SRP-dependent pathways were equally viable methods, with more research being done into the Sec-dependent pathway, particularly of the OmpA signal sequence. Physical experiments were done using typical cloning procedures with slight modifications to the ligation step (Gibson Assembly was performed instead of normal ligation). These physical experiments showed that the Sec-dependent and SRP-dependent pathways were equally viable methods of periplasmic entry. The A4 and C6 antibodies were successfully expressed using these pathways. These antibodies were expressed on an SDS gel using 10% SDS. It was hypothesized that with further experimental modifications, using different signal sequences, Fabs can be expressed at higher and more consistent level.
ContributorsParker, Matthew David (Author) / Nannenga, Brent (Thesis director) / Nielsen, David (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Rotary equipment has been used widely in the processing of particulates for the last century, but low thermal efficiency and poor effluent uniformity continue to plague its performance. Consequently, these technologies contribute largely to modern energy waste, environmental pollution, and price inflation of products dependent on particulates in their manufacture. Large industries like pharmaceuticals and oil are impacted, yet minimal research has been conducted into optimizing the equipment because of costs associated with process shut-downs necessary to enable study. Recent works bypassed this constraint with simulations and scaled-down replicates to observe impact of common design parameters, fill level and rotation speed, on heating. This thesis supplanted these studies by investigating particle diameter as a control parameter to optimize heating. The thesis investigated methodologies to study a stainless-steel rotary drum model facilitating the conductive heating of a silica bed by external heat guns. Diameter was varied 2-4 mm at controlled fill levels and rotation speeds, and radial temperature profiles were measured with thermocouples. Heating performance was evaluated for efficiency and uniformity; the former by analyzing thermal time constants and average temperature progression across 70 minutes of operation, and the latter with corresponding radial temperature variances. It was theorized that the direct influence of size on transport properties would implicate an inverse correlation between diameter and performance, but results demonstrated no significance. The apparatus and methodology were still under development, so results were preliminary. From results, the study proposed setup modifications to refine results and future directions to guide follow-up research.
ContributorsDeBruin, Dylan (Author) / Emady, Heather (Thesis director) / Adepu, Manogna (Committee member) / Chemical Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Genetic manipulation of human cell lines has widespread applications in biomedical research ranging from disease modeling to therapeutic development. Human cells are generally difficult to genetically engineer, but exogenous nucleic acids can be expressed by viral, chemical, or nonchemical means. Chemical transfections are simpler in practice than both viral and nonchemical delivery of genetic material, but often suffer from cytotoxicity and low efficiency. Novel aminoglycoside antibiotic-derived lipopolymers have been synthesized to mediate transgene delivery to human cells. These polymers are comprised of either paromomycin or apramycin crosslinked with glycerol diglycidylether and derivatized with stearoyl chloride in varying molar ratios. In this work, three previously identified target lipopolymers were screened against a library of human embryonic and induced pluripotent stem cell lines. Cells were transfected with a plasmid encoding green fluorescent protein (GFP) and expression was quantified with flow cytometry 48 hours after transfection. Transfection efficiency was evaluated between three distinct lipopolymers and four lipopolymer:DNA mass ratios. GFP expression was compared to that of cells transfected with commercially available chemical gene delivery reagent controls\u2014JetPEI, Lipofectamine, and Fugene\u2014at their recommended reagent:DNA ratios. Improved transgene expression in stem cell lines allows for improved research methods. Human stem cell-derived neurons that have been genetically manipulated to express phenotypic characteristics of aging can be utilized to model neurodegenerative diseases, elucidating information about these diseases that would be inaccessible in unmanipulated tissue.
ContributorsMehta, Frea (Author) / Brafman, David (Thesis director) / Rege, Kaushal (Committee member) / Chemical Engineering Program (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The objective of this research study is to assess the effectiveness of a poster-based messaging campaign and engineering-based activities for middle school and high school students to encourage students to explore and to pursue chemical engineering. Additionally, presentations are incorporated into both methods to provide context and improve understanding of the presented poster material or activity. Pre-assessments and post-assessments are the quantitative method of measuring effectiveness. For the poster campaign, ASU juniors and seniors participated in the poster campaign by producing socially relevant messages about their research or aspirations to address relevant chemical engineering problems. For the engineering-based activity, high school students participated in an Ira A. Fulton Schools of Engineering program "Young Engineers Shape the World" in which the students participated in six-hour event learning about four engineering disciplines, and the chemical engineering presentation and activity was conducted in one of the sessions. Pre-assessments were given at the beginning of the event, and the post-assessments were provided towards the end of the event. This honors thesis project will analyze the collected data.
ContributorsBueno, Daniel Tolentino (Author) / Ganesh, Tirupalavanam (Thesis director) / Parker, Hope (Committee member) / Chemical Engineering Program (Contributor) / School of Historical, Philosophical and Religious Studies (Contributor) / W. P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Polymer modified tuning fork-based sensors were fabricated to assure reproducibility. The effect of system valve switching on the modified tuning fork-based sensors was studied at the different temperature. The response to Xylene gas sample on stabilized modified tuning fork-based sensors with temperature was defined while learning about the key analytical performance for chemical sensors to be used in the real-world application.
ContributorsRohit, Riddhi S (Author) / Forzani, Erica (Thesis director) / Tsow, Francis (Committee member) / Dean, W.P. Carey School of Business (Contributor) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The overall goal of this project is to use metallic nanoparticles to develop a thin, ductile amorphous film at room temperature. Currently bulk metallic glasses are mainly formed via quenching, which requires very high cooling rates to achieve an amorphous molecular structure. These formations often fail in a brittle manner. The advantages of using a bottom-up approach with amorphous nanoparticles at ambient conditions is that the ductility of the metal can be improved, and the process will be less energy intensive. The nanoparticles used are iron precursors with ATMP and DTPMP ligand stabilizers and dispersed in methanol. Three forms of experimentation were applied over the course of this project. The first was a simple, preliminary data collection approach where the particles were dispersed onto a glass slide and left to dry under various conditions. The second method was hypersonic particle deposition, which accelerated the particles to high speeds and bombarded onto a glass or silicon substrate. The third method used Langmuir-Blodgett concepts and equipment to make a film. Qualitative analyses were used to determine the efficacy of each approach, including SEM imaging. In the end, none of the approaches proved successful. The first approach showed inconsistencies in the film formation and aggregation of the particles. The results from the hypersonic particle deposition technique showed that not enough particles were deposited to make a consistent film, and many of the particles that were able to be deposited were aggregated. The Langmuir-Blodgett method showed potential, but aggregation of the particles and uneven film formation were challenges here as well. Although there are ways the three discussed experimental approaches could be optimized, the next best step is to try completely new approaches, such as convective assembly and 3D printing to form the ideal nanoparticle film.
ContributorsKline, Katelyn Ann (Author) / Lind, Mary Laura (Thesis director) / Cay, Pinar (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Zeolite thin films and membranes are currently a promising technology for pervaporation, gas separation and water purification. The main drawback with these technologies is that the synthesis is not consistent leading to varied and unreproducible results. The Langmuir-Blodgett technique is a robust method for transferring monolayers of molecules or crystals to a solid substrate. By measuring the surface pressure and controlling the area, reliable results can be achieved by transferring monolayers to different solid substrates. It has been shown previously that various types of zeolites can be functionalized and dispersed on the top of water. This is done by using an alcohol to form a hydrophobic coating on the surface of zeolite. The Langmuir-Blodgett can be used to create thin, compact films of zeolites for synthesizing and growing zeolite films. For the first reported time, cubic LTA Zeolites monolayers have been assembled with the Langmuir-Blodgett technique with multiple solvents and different sizes of zeolites. These films were characterized with Scanning Electron Microscopy and Pressure-Area Isotherms generated from the Langmuir-Blodgett. It was found that linoleic acid is a required addition to the zeolite dispersions to protect the mechanical stability during agitation. Without this addition, the LTA zeolites are broken apart and lose their characteristic cubic structure. This effect is discussed and a theory is presented that the interparticle interactions of the long alkane chain of the linoleic acid help reduce the shear stress on the individual zeolite particles, thus preventing them from being broken. The effect of size of the zeolites on the monolayer formation was also discussed. There seemed to be little correlation between the monolayer quality and formation as size was changed. However, to optimize the process, different concentrations and target pressures are needed. Lastly, the effect of the solvent was explored and it was found that there is a different between monolayer formations for different solvents likely due to differing interparticle interactions. Overall, LTA zeolites were successfully fabricated and the important factors to consider are the zeolite size, the solvent, and the amount of surfactant stabilizer added.
ContributorsDopilka, Andrew Michael (Author) / Lind, Mary Laura (Thesis director) / Cay, Pinar (Committee member) / Materials Science and Engineering Program (Contributor) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Microbial dysbiosis is a condition where one’s gut bacteria colonies and species are imbalanced due to infection, antibiotics, and diet. Dysbiosis can lead to chronic illnesses like inflammatory bowel disease where current clinical treatments, such as probiotics and fecal matter transplant, have limitations from precisely delivering the right bacteria species in the right location in the gastrointestinal tract. With recent developments of magnetically actuated endoscopy bots which are precisely controlled and less invasive, magnetically-controlled robotic solutions can be applied to solving microbial dysbiosis. Two GI bot designs were developed, an accordion and concertina design, which differ in geometry. These designs involved a soft Ecoflex body, four ring magnets that are made of NdFeB and Ecoflex (in a 4:1 weight ratio) and magnetically actuated in the same direction, and a 3D-printed plastic capsule. The design rationale involved introducing the GI bot to external magnetic fields to deliver a payload, i.e. bacteria, for an application in solving microbial dysbiosis.
First, the design was optimized. Tensile and compression testing were used to determine an optimal Ecoflex coating combination with Ecoflex 00-10 making the first layer and Ecoflex 00-50 making the second layer. Afterward, two main functions were tested for in the robot: (1) precise magnetic control of the robot’s movement and direction and (2) magnetic control of the GI bot’s compression to trigger a payload release. Orientation control of the GI bot was demonstrated with a robot arm introducing a magnetic field of 4.08 mT. The test demonstrated proper control of the robot for five degrees of freedom. Lastly, delivery capabilities for the designs were established under a 173 mT external magnetic field with the accordion and concertina having dyed water (payload) release efficiencies of 35.33% and 40.16% respectively. From these results, a GI bot in the gut is achievable, and the accordion or concertina models provide a basis for further exploring and optimizing the safety and efficiency of this clinical robotic and magnetic solution. Moreover, the results showcase that magnetic actuation can be used for both orientation and delivery control as they are decoupled based on the external magnetic field strength.
ContributorsNguyen, Sophie (Author) / Marvi, Hamidreza (Thesis director) / Ceylan, Hakan (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / Chemical Engineering Program (Contributor)
Created2023-12
Description
Globally Hummus is a food brand that reimagines hummus by offering clean, plant-based recipes inspired by global cuisines. Its flagship product, Thai Red Curry Hummus, combines traditional chickpeas with bold, international flavors to create a unique and versatile snack. The company targets health-conscious individuals and adventurous eaters who value quality, convenience, and cultural exploration. Globally Hummus uses sustainable practices, creative branding, and social media engagement to build community and encourage exploration through food.
ContributorsNair, Dhruv (Author) / Aggarwal, Arnav (Co-author) / Prem, Prithvi (Co-author) / Rusconi, Jackson (Co-author) / Fricke, Ethan (Co-author) / Byrne, Jared (Thesis director) / LaRosa, Julia (Committee member) / Barrett, The Honors College (Contributor) / Department of Finance (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Department of Information Systems (Contributor)
Created2025-05
Description
Globally Hummus is a food brand that reimagines hummus by offering clean, plant-based recipes inspired by global cuisines. Its flagship product, Thai Red Curry Hummus, combines traditional chickpeas with bold, international flavors to create a unique and versatile snack. The company targets health-conscious individuals and adventurous eaters who value quality, convenience, and cultural exploration. Globally Hummus uses sustainable practices, creative branding, and social media engagement to build community and encourage exploration through food.
ContributorsAggarwal, Arnav (Author) / Nair, Dhruv (Co-author) / Fricke, Ethan (Co-author) / Prem, Prithvi (Co-author) / Rusconi, Jackson (Co-author) / Byrne, Jared (Thesis director) / LaRosa, Julia (Committee member) / Barrett, The Honors College (Contributor) / Department of Finance (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Department of Information Systems (Contributor)
Created2025-05