REU Past Students
Jacqueline Anatot - Biochemistry, University of Florida
Educational Institution: University of Florida
List of Mentors: Dr. John Wilson & Taylor Sheehy
Program: NSF REU
Research Project: Macrophage-Targeted Polymer-Drug Conjugates for STING Pathway Activation to Improve Cancer Immunotherapy
Poster: NSF REU Jacqueline Anatot Poster
Research Abstract: The cGAS-STING pathway plays a crucial role in the immune recognition and elimination of cancer cells, and STING agonists are being explored as next- generation cancer immunotherapeutics. Specifically, STING activation has the potential to reprogram tumor-associated macrophages (M2) into an anti-tumor phenotype (M1), further facilitating cancer clearance. STING agonists suffer from poor drug-like properties and off-target toxicities, which could be mitigated using drug delivery systems. Therefore, we aim to develop a tumor and macrophage-targeted, polymer-drug conjugate that enhances macrophage uptake of STING agonists. Due to the overexpression of the mannose receptor in M2-macrophages, mannose serves as a promising cell-targeting agent. Through Reversible Addition-Fragmentation Chain Transfer (RAFT) polymerization, we synthesized 100kDa poly(N,N-dimethylacrylamide-co-Azide ethylmethacrylate-co-Mannose) terpolymers with various mannose composition. The DMA backbone enables efficient drug solubilization and prolonged circulation, while the presence of AzEMA permits conjugation of DBCO-functionalized STING agonists. Murine macrophage cell lines were polarized to an M2-phenotype and utilized to investigate uptake of our polymers. As expected, mannose functionalized polymers demonstrated enhanced uptake in M2 macrophages. An ongoing biodistribution study aims to further validate enhanced macrophage uptake by measuring polymer accumulation within macrophage-rich organs. Future studies will incorporate a STING agonist onto the lead polymer platform and demonstrate its ability to repolarize macrophages and enhance antitumor immunity. This study contributes to the advancement of polymer-drug conjugates, unlocking unparalleled potential in the realm of drug delivery technology to revolutionize therapeutic outcomes.
Bio. Jacqueline Anatot is a rising senior pursuing a B.S. in Biochemistry with a minor in MSE at the University of Florida. She is currently working as an undergraduate research assistant in Dr. Brent S. Sumerlin's research group and recently released a publication in the JACS titled: “Degradation of Polyacrylates by One-Pot Sequential Dehydrodecarboxylation and Ozonolysis.” Jacqueline is a recipient of the prestigious CLAS Sciences Scholars program as well as the Bristol-Myers Squibb Scholars Program. She is involved in the UF Chemistry club Outreach Initiative and intends to pursue a PhD in BME, specifically focusing on mechanisms to treat and prevent disease.
Taylor Baugher - Biomedical Engineering, Georgia Institute of Technology
Educational Institution: Georgia Institute of Technology
List of Mentors: Dr. William Fissell & Dr. Harold Love
Program: NSF REU
Research Project: Inducible Gene Expression to Drive Cell Differentiation in Renal Tubule Epithelial Cells In Vitro
Poster: NSF REU Taylor Baugher Poster
Research Abstract: The growing use of tissue and cell cultures for the development of organ replacement therapies has brought about challenges regarding the differentiation of cultured cells. Renal tubule epithelial cells are specialized to carry out vital functions in the kidney such as reabsorption and secretion. These cells express genes such as NHE3, AQP1, and N-Cadherin to aid in water and ion transport. However, in vitro renal tubule epithelial cells lack the transcriptional profile to fully differentiate, decreasing transport, polarization, and metabolic activity compared to their in vivo counterparts. This presents challenges to biomedical research as cultures are used for bio-inspired design and conceptual frameworks. Cell differentiation in intestinal epithelial cells in vitro is activated by a serine/threonine kinase encoded by a tumor suppressor gene, LKB1, with the help of an LKB1-specific adaptor protein, STRAD- (Baas et. al 2004). Using a cumate gene-switch system integrated into a piggyBac transposon, we studied how induced expression of the LKB1 and STRAD- genes would influence renal epithelial cell differentiation in vitro. Gene expression analyses proved STRAD- and LKB1-induced cells significantly expressed more proximal tubule biomarkers when compared to control renal proximal tubule epithelial cells, but this was not dependent upon transgene expression. These findings suggest a transcriptional variation between clones that could aid in isolating new cell lines with better differentiation for future biomedical research.
Bio. Taylor Baugher is a rising third-year in the B.S. Biomedical Engineering program at the Georgia Institute of Technology. In the past, Taylor has worked as a data curator for the Pathology Dynamics Lab at Georgia Tech, where she used data mining and quality control techniques to aid in the buildout of a natural language processing model for drug repurposing. Currently, Taylor serves as the secretary for Bioinformatics at GT, a club that expands the knowledge of computational biology across campus. For the upcoming year, Taylor will serve as a teaching assistant in the biomedical engineering department at Georgia Tech, guiding first-year students through the development of their skills as academics and employees. As for graduate school, she hopes to dive more into the role of bioinformatics for personalized medicine along with expanding her current knowledge of genome engineering for biomedical applications.
- Baugher was awarded Best Layout at the capstone poster session.
Emily Buckner - Mechanical Engineering, University of of Tennesee, Knoxville
Educational Institution: University of Tennesee, Knoxville
List of Mentors: Dr. Xiaoguang Dong & Boyang Xiao
Program: NSF REU
Research Project: Wirelessly Actuated Soft Miniature Robots with Integrated Microfluidic Modules for Targeted Drug Delivery
Poster: NSF REU Emily Buckner Poster
Research Abstract: The inherent softness of soft robots offers unique advantages in medical applications where safe interaction with surrounding biological tissues is crucial. Soft robots made of smart soft materials allow for programmable functionalities by spatially patterning material properties. More recently, magnetic actuation has gained significant attention due to its ability to wirelessly control soft robots for medical operations. Despite recent advances, the development of wireless soft robots for minimally invasive medical procedures that can traverse complex terrains remains challenging. In this study, we propose an untethered soft robot actuated by magnetic fields and integrated with microfluidic channels to achieve on-demand and targeted drug delivery in complex, confined environments within the body, such as the gastrointestinal (GI) tract. The robot, constructed at the millimeter scale through laser lamination and layer-by-layer assembly, boasts optimized material properties and dimensions to facilitate multi-modal locomotion and targeted drug delivery functions. By employing a tailored magnetization profile design, the robot exhibits various modes of locomotion, including crawling and climbing. Furthermore, the integration of microfluidic channels into the robot body, along with an origami-inspired self-folding pump and flexible valve, enables precise control of drug delivery. To actuate the robot's movement, we have designed a customized electromagnet array that accurately directs and regulates the magnitude of the applied magnetic field. Finally, we experimentally validate the robot's locomotion and drug delivery capabilities in phantom structures. This novel soft robot design holds great potential to navigate complex terrains and serve therapeutic functions in biomedicine as well as on-demand and targeted drug delivery, minimizing the side effects of overdosing during medical treatments.
Bio. Emily Buckner is a rising senior at the University of Tennessee, Knoxville pursuing a degree in mechanical engineering. She became involved in undergraduate research in the Advincula Lab where she works jointly between the Institute for Advanced Materials and Manufacturing and Oak Ridge National Laboratory on the additive manufacturing of nanocomposites. For this research, she has been awarded two research grants, presented at national conferences, and co-authored the paper “Digital Light Processing (DLP): 3D printing of polymer-based graphene oxide nanocomposites—Efficient antimicrobial material for biomedical devices”. In addition to research, Emily is the President of the Tau Beta Pi Tennessee Alpha chapter, an ambassador to UT’s Engineering Professional Practice Office, and involved in the Society of Women Engineers.
- Buckner was awarded a $1K travel grant at the capstone poster session.
Erin Burgard - Environmental Engineering, Arizona State University
Educational Institution: Arizona State University
List of Mentors: Dr. Richard Haglund & Jackson Bentley
Program: NSF REU
Research Project: Using Machine Learning with Porous Silicon to Determine IgG Concentrations in Human Serum
Poster: NSF REU Erin Burgard Poster
Research Abstract: Conventional solar panels currently operate at a low efficiency of approximately 25%. However, Mott insulators present a promising avenue for enhancing solar energy conversion as they have shown a theoretical potential to achieve over 65% efficiency. Impaction ionization occurs in a semiconductor if the kinetic energy of the charge carrier is greater than twice the bandgap, which may then excite an additional electron-hole pair. In Mott insulators, this process occurs over one hundred times faster than a typical semiconductor (i.e. silicon), which contributes to almost doubled efficiency, and the possibility of creating multiple charge carriers per photon absorption. The Mott insulator proposed to be used in solar energy is LVO (lanthanum vanadium oxide). However, this research focuses on V2O3 because it is a strongly correlated material that is easier to work with in the preliminary investigation of the multiexciton generation process. The films were synthesized using sputtering and annealing techniques, and characterized with xray diffraction, Raman spectroscopy, scanning electron microscopy, and atomic force microscopy. Using this model Mott insulator thin film, we successfully established a reliable recipe detailing the sputtering and annealing procedures for producing quality thin V2O3 films. This investigation contributes to the advancement of solar panel technology by providing a better understanding of Mott insulator synthesis and offering a potential avenue for improving solar energy conversion efficiency by studying impact ionization in a model Mott insulator system.
Bio. Erin Burgard is an honors undergraduate senior at Arizona State University, where she majors in Environmental Engineering and minors in Spanish and Environmental Humanities. This summer, she is researching at Vanderbilt University, where she is synthesizing and characterizing Mott insulators for solar cell applications. At ASU, she researches the stress response of perovskite thin films for use in solar cells. This work was supported by her honors thesis which was defended in May 2023 and awarded the Bidstrup fellowship, Mensch prize, Jaap Sustainability scholarship, and Fulton Undergraduate Research Initiative. Erin also works with the international water treatment non-profit 33 Buckets and spent two months in the rural communities in the outskirts of Cusco, Peru conducting research surveys and assessments. Within ASU, Erin worked as a first-generation engineering student mentor for the Fulton Engineering School with the objective to increase the retention of first-generation students in engineering. She also started a small business selling hand painted cards. She will graduate in May of 2024.
- Burgard was $1K in the VINSE summer image competition
Andres Cotto - Chemical Engineering, University of South Florida
Educational Institution: University of South Florida
List of Mentors: Dr. Sharon Weiss & Kellen Arnold
Program: NSF REU
Research Project: Design and Characterization Techniques to Advance Integrated Photonics for Space Missions
Poster: NSF REU Andres Cotto Poster
Research Abstract: Photonic integrated circuits are hybrid circuit designs that marry the data transmission efficiency of optical signaling with the compact, powerful data processing of electrical integrated circuits on a single chip. Integrated photonics research has led to strong commercial applications in communications, biosensing, and quantum computers. There is also a strong desire to develop integrated photonics for space missions, where the size, weight, power, and performance advantages of on-chip photonic systems can improve the capabilities of scientific equipment. In the Weiss group, we innovate photonic design and characterization methods for enhancing light-matter interactions at the nanoscale to advance on-chip photonic component performance and revolutionize space industry equipment. This summer, we compared energy redistribution between different nanoscale geometries in specially-designed periodic cavities in silicon waveguides, called photonic crystals. Using electromagnetic simulations, the photonic crystal unit cell designs can be tailored to match fabrication capabilities with design specifications. As we develop these photonic crystal designs, the Weiss group also works on commercially-viable photonic crystals, which are fabricated using deep ultraviolet lithography. We developed a polishing and etching technique that removes the coatings from commercially fabricated chips to reveal the photonic structures below the surface. This procedure is useful for imaging for publications and design feedback and will also be used in the future for space environment testing with/without encapsulation and biosensing experiments.
Bio. Andres M. Cotto is a rising junior at the University of South Florida, where he is earning his Bachelor of Science in Chemical Engineering. When not in the classroom, he works as an undergraduate researcher under Dr. Ryan Toomey, where he researched materials ellipsometry and developed an interest in learning about photonics. In addition to his work in curricula and research, Andres works as the elected Events Chair for the USF chapter of the American Institute of Chemical Engineers, and as the Operations Director for the USF chapter of Society of Hispanic Professional Engineers. Andres came to VINSE out of an interest to learn more about materials engineering, where he could gain insight into the life of research from Vanderbilt’s research groups. He hopes to one day use his chemical engineering knowledge for the synthesis of materials used in cutting edge, high-efficiency electronics and clean energy solutions. The industries he is most interested in are renewable energy, solar cell technologies, and the space industry.
- Conference Presentation
Anya Frazer - Physics, University of North Carolina, Chapel Hill
Educational Institution: University of North Carolina, Chapel Hill
List of Mentors: Dr. Greg Walker & Brad Baer
Program: NSF REU
Research Project: Thermal Conductivity Across Metal/Metal Oxide Interfaces
Poster: NSF REU Anya Frazer Poster
Research Abstract: Catalytic cracking of ethane to ethylene uses a large amount of heat energy, much of which goes to waste. The National Renewable Energy Laboratory has proposed a new method to reduce heat waste, which involves inductively heating the reaction through a layered metal/metal oxide device. We demonstrate a computational method for predicting thermal conductivity across nonequilibrium metal/metal oxide systems using molecular dynamics (MD) with a two-temperature model (TTM). The TTM allows for thermal conductivity to be modeled as a combination of lattice and electronic contributions by governing the exchange of energy between the lattice and an electronic subsystem. Iron and iron oxide were chosen as the model materials to demonstrate our method. Our method predicts the thermal conductivities of bulk iron and iron oxide to the same order of magnitude as experiment. The addition of the TTM improved the prediction of thermal conductivity of iron compared to MD alone, indicating that electronic contributions are significant in the thermal conductivity of iron. Our system predicted a large temperature drop across the metal/metal oxide interface. The TTM created a more physical representation of heat traveling through iron, but was not applicable to the iron oxide due to a deficiency of conduction electrons. Our approach is transferrable to other metal/insulator systems.
Bio. Anya Frazer is a rising sophomore at UNC Chapel Hill, double majoring in physics and music. Prior research experience includes a senior capstone studying the impact of practice habits on harmonic content of middle and high school flute players’ tone, as well as participation in a large-scale literature review through NASA’s Backyard Worlds research group to catalogue known qualities of star systems within 20 parsecs. She has made the Dean’s List during both of her semesters at UNC. Anya hopes to get a diverse range of research experiences in her undergraduate career to prepare her for pursuing a PhD in physics. When she is not studying physics, you can find her playing the flute in UNC’s Wind Ensemble and in solo performances.
- Conference Presentation
Jonathan Gonzalez - Mechanical Engineering, University of Puerto Rico
Educational Institution: University of Puerto Rico
List of Mentors: Dr. Cynthia Reinhart-King & Jenna Mosier & Emily Fabiano
Program: NSF REU
Research Project: Understanding the Role of Microtubules and Focal Adhesions in Breast Cancer Cell Migration
Poster: NSF REU Jonathan Gonzalez Poster
Research Abstract: Cancer metastasis, an advanced stage of cancer, is responsible for 90% of cancer-related deaths. In this process, cancer cells migrate from the primary tumor to different regions in the human body to form secondary sites. Cell migration is a complex stage in this process requiring the coordination of cytoskeletal components and focal adhesions. Microtubules provide structure as well as internal organization of the cell. Vinculin, a key focal adhesion protein, connects the surrounding matrix and the cell cytoskeleton. Microtubule destabilization has previously been reported to increase focal adhesion size, resulting in increased vinculin recruitment to focal contact sites. While previous research has primarily focused on the physical link between actin and focal adhesions, or the individual roles of microtubules and focal adhesions, the interplay of vinculin and microtubule dynamics in directing cancer cell behavior is still unknown. To assess this relationship, we created a vinculin-knockout cell line using CRISPR/Cas9 and visualized microtubules using a live-cell dye. Additionally, we used nocodazole, a pharmacological agent to disrupt microtubule polymerization, to understand how migration is affected by microtubule and vinculin organization. Using 500 nM nocodazole treatment, we found that microtubule front:rear distribution was significantly decreased in control, but not vinculin-knockout cells. Control cells moderately decreased velocity, while no change was observed in vinculin-knockout cells with treatment. Future work in this project will involve using representative, 3D collagen microtracks to further elucidate the role of vinculin and microtubules in a physiologically relevant environment to potentially highlight key therapeutics for treating cancer metastasis.
Bio. Jonathan Gonzalez is a rising junior at the University of Puerto Rico Mayagüez studying mechanical engineering. Through his education journey, he had the opportunity to join the research team Innovating Design Decisions in Engineering and Applied Systems (IDDEAS) and optimized patient waiting time at a cardiologist’s office. Here, he collected and analyzed samples to improve patient waiting time. Furthermore, he shadowed the creation of A3B, an emergency ventilator with the aim of being the first FDA-approved ventilator in Puerto Rico. Currently he is an REU student at the Vanderbilt Institute of Nanoscale Science and Engineering (VINSE) investigating microtubule-mediated behavior of vinculin knockout breast cancer cells in confined migration. After completing his undergraduate degree, Jonathan aspires to obtain a Ph.D. in biomedical engineering to further his contributions to healthcare.
Raey Hunde - Chemical Engineering, University of Maryland, Baltimore County
Educational Institution: University of Maryland, Baltimore County
List of Mentors: Dr. Ethan Lippmann & Corinne Curry
Program: NSF REU
Research Project: Stimulating Collateral Arterial Growth Using Acellular, Growth-Factor Free Hydrogels for the Treatment of Critical Limb Ischemia
Poster: NSF REU Raey Hunde Poster
Research Abstract: Critical Limb Ischemia (CLI) is a condition that affects millions of people all over the world who may suffer from diabetes or are chronic smokers. It is a severe blockage in the arteries caused by a buildup of plaque that significantly reduces blood flow to lower extremities like the legs. The lack of blood flow causes the surrounding tissue to become necrotic, thus requiring amputation. As of now, CLI lacks a lot of robust treatment options. In the past, clinical trials have attempted to stimulate arterial growth using growth-factor encapsulated hydrogels. Unfortunately, these clinical trials have failed to appreciably improve patient outcomes. We propose an alternative method that uses acellular-growth factor-free hydrogels to stimulate arteriogenesis. This methodology is twofold: (1) to further develop and characterize a previously studied GelCad hydrogel (gelatin-based hydrogel with Cadherin peptides attached) and synthesize this GelCad hydrogel into microspheres, and (2) to implement a cell-responsive siRNA release strategy that will trigger arteriogenesis through macrophage polarization. Preliminary results suggest GelCad microspheres can be synthesized using both a 4-Arm PEG SG (negative control) and 3,3′-Dithiodipropionic acid di(N-hydroxysuccinimide ester) (positive control) crosslinkers. 3,3′-Dithiodipropionic acid di(N-hydroxysuccinimide ester) is a reactive oxygen species or ROS active and is capable of macrophage polarization.
Bio. Raey Hunde is a rising senior chemical engineering student at the University of Maryland, Baltimore County. She has researched biomedical and chemical engineering at the following institutions: FDA: CBER, Laboratory of Virology, University of Minnesota: Twin Cities, University of Maryland, Baltimore County, Purdue University, and Vanderbilt University. Raey is a Meyerhoff and U-RISE scholar at the University of Maryland, Baltimore County, and aspires to obtain her Ph.D. in chemical engineering after graduation.
Shereena Johnson - Bioengineering, Rice University
Educational Institution: Rice University
List of Mentors: Dr. Marjan Rafat & Tian Zhu
Program: NSF REU
Research Project: Irradiated Extracellular Matrix Effects on Breast Cancer Cell Invasion
Poster: NSF REU Shereena Johnson Poster
Research Abstract: Triple negative breast cancer (TNBC) has a significantly higher rate of locoregional recurrence after radiation therapy than other forms of breast cancer but has limited treatment options due to the lack of targetable hormone and protein receptors. Previous work has shown that recurrence is caused by increased recruitment of circulating breast cancer cells to the irradiated site. However, the change to the tumor microenvironment that leads to increased invasion is unknown. This project aims to determine whether the irradiated extracellular matrix (ECM) is responsible for increased TNBC cell invasion through the study of irradiated ECM hydrogels. ECM hydrogels were created using mammary fat pads (MFPs) extracted from immunocompromised Nu/Nu mice. MFPs were irradiated to a dose of 20 Gy ex vivo using a cesium source, decellularized to ECM components, and formed into hydrogels through pH-controlled restructuring of the ECM environment. Murine TNBC cell invasiveness in irradiated vs. non-irradiated control ECM hydrogels was measured via colocalization of F-actin and cortactin in 4T1 cells embedded into the hydrogels for 48 hours, staining and imaging of E-cadherin and vimentin proteins, and an invasion assay.
Using fluorescence microscopy, we determined an increase in colocalization of F-actin and cortactin in 4T1 cells as well as increased invasion when embedded into irradiated ECM hydrogels. We also observed cell morphology changes toward a more invasive phenotype and increased expression of E-cadherin and vimentin proteins in irradiated ECM hydrogels. These results suggest that the isolated effect of ECM changes contribute to increased TNBC invasion after radiation therapy. Future work will focus on analyzing altered individual protein components of the ECM and interactions between immune cells and cancer cells in the irradiated microenvironment.
Bio. Shereena Johnson is a third-year undergraduate student, studying Bioengineering at Rice University in Houston, TX. She is originally from Orlando, Florida and attends Rice as a Questbridge Scholar. During her time at Rice, she contributed to research at the Tabor Lab in the Department of Bioengineering, which focuses on the study and manipulation of bacterial gene networks for use in disease diagnosis and drug delivery. Shereena is an active contributor to the engineering community at Rice through her roles as a Writing Mentor for Introductory Engineering Design Courses, the Fundraising Senator for the National Society for Black Engineers Executive Board, and through her future role as a Teaching Assistant for Fundamentals of Bioengineering.
Deborah Oke - Chemistry, Northeastern University
Educational Institution: Northeastern University
List of Mentors: Dr. Janet Macdonald & Tony Peng
Program: NSF REU
Research Project: Rediscovering Lost Rock Art Painting Techniques
Poster: NSF REU Deborah Oke Poster
Research Abstract: Hundreds of years ago, the Anishinaabe people of the northern US and Southern Canada region painted on cliff sides along lakes, which leaves their art susceptible to wear and erosion – or so one would think. How to create these long lasting works of art have been lost within the culture. Previous studies have found that the main pigment is hematite, and a substance with high amounts of silicon are found below, above, and mixed within the paint layer. Using various plants native to the region and of cultural -significance, different lyes were made from the ashes of these plants to create a natural source of silica that can be painted. The silicon content of the lye was dependent on the ashing time and the identity of the plant. Chemical analysis techniques including Inductively Coupled Plasma Optical Emission Spectroscopy and X-ray Fluorescence were used to analyze the amounts of silicon in the lyes. Lyes made from sweet grass and horsetail had the highest amounts of silicon in them relative to other plants including cedar, red osier dogwood, and tamarack bark. In regards to painting, the use of water glass to represent the silicon layer beneath and above the paint aided in the overall durability. Going forward, additional plants will be used to continue making and testing lyes, as well as industrial tests to provide quantitative analysis of the durability of the paint.
Bio. Deborah Oke is a rising second year Honors student at Northeastern University, studying chemistry. She is a member of Northeastern University's Student Affiliates of the American Chemical Society, NuSci, and serves as an Honors Ambassador. During her first year, she created a curriculum surrounding molecular structure and bonding theories to be taught at a local high school, got to volunteer with the American Chemical Society for National Chemistry Week, and has aided Northeastern’s Department of Chemistry by being a student interviewer for potential faculty members. She hopes to join a lab at her home institute this fall to continue expanding her research experience.
- Oke was awarded Best Use of Graphics at the capstone poster session.
Ellie Okonak - Biomedical Engineering, Bucknell University
Educational Institution: Bucknell University
List of Mentors: Dr. Craig Duvall & Amelia Soltes
Program: NSF REU
Research Project: Nanoparticle Development For siRNA Delivery To Treat Osteoarthritis (OA)
Poster: NSF REU Ellie Okonak Poster
Research Abstract: Osteoarthritis (OA) is a degenerative joint disease that affects over 32 million US adults and currently has no cure; treatments for OA focus on alleviating symptoms and include lifestyle changes, pain-relieving medications, and joint replacements. Short interfering RNA (siRNA) has the capability to degrade protein-producing mRNA, which can be used in OA to prevent the expression of the gene that drives cartilage degradation and ultimately inhibit disease progression. However, siRNA delivery is challenging in vivo due to issues such as endosomal escape and kidney clearance. One alternative method of delivery is loading the siRNA into polymeric nanoparticles (si-NPs) that enable siRNA to be delivered into the cell. The purpose of this project was to optimize nanoparticle formulation using a confined impinging jets mixer (CIJ) for effective siRNA delivery.
Various formulations of si-NPs were made using a CIJ mixer with solvent and antisolvent streams. The si-NPs contain a core consisting of poly(dimethylaminoethyl methacrylate-co-butyl methacrylate) (DB) to enable endosomal escape and poly(lactide-co-glycolide) (PLGA) for nanoparticle stability. DSPE-PEG (lipid-PEG) was used as a surfactant for biocompatibility and to prevent si-NP aggregation. The ratio of DB to PLGA in the si-NP core was varied, as well as the ratio of amines to phosphates (N:P), in order to optimize the gene silencing activity and toxicity of the si-NPs. The si-NPs were analyzed for size, zeta potential, and siRNA delivery capability. The formulation concentrations of 3 mg/mL of DB and PLGA in the solvent stream and 1 mg/mL lipid-PEG in the antisolvent stream were found to be the most successful for nanoparticle formation using the CIJ mixer. Studies investigating the gene silencing activity of the different si-NP formulations are ongoing.
Bio. Ellie is a rising third year biomedical engineering major at Bucknell University in Lewisburg, PA. She works as a study group facilitator for Chemistry and Calculus II students on-campus, and has been a teaching assistant for various calculus classes since her freshman year. Ellie also leads tours as an ambassador for the Office of Admissions, and has served on the Biomedical Engineering Society executive board. Ellie’s involvement in a sophomore year cell culturing class sparked her interest in drug delivery research, which further led her to Professor Duvall’s Advanced Therapeutics Laboratory through the VINSE REU. Ellie plans to pursue her PhD in biomedical engineering, and is grateful for the knowledge and support she gained this summer.
Ethan Ray - Materials Science and Engineering, Georgia Institute of Technology
Educational Institution: Georgia Institute of Technology
List of Mentors: Dr. Josh Caldwell & Saurabh Dixit
Program: NSF REU
Research Project: Controlling and Manipulating Confined Infrared Light in MoO3 via Polaritonic Design
Poster: NSF REU Ethan Ray Poster
Research Abstract: The Infrared (IR) spectrum of light is crucial for various applications such as thermal imaging, molecular sensing, free space communication, and many others. However, the long free-space wavelength of IR light greatly limits its applications in chip-scale devices. This problem can be circumvented using hyperbolic van der Waals materials that exhibit hyperbolic anisotropy in which the dielectric permittivities along the principal crystal directions exhibit opposite signs. Such hyperbolic materials can confine high-momentum (short wavelength) electromagnetic waves with the help of phonon polaritons — a quasi-particle made up of the hybridization of charged dipoles in a crystal and photons (an external light source). In this work, we investigate sub-wavelength wedges of a hyperbolic material known as alpha-phase molybdenum trioxide (α-MoO3) to demonstrate in-plane tight focusing of electromagnetic waves beyond the diffraction limit. We design our wedges by optimizing geometrical dimensions using 3D numerical simulations. Thereafter we fabricate such structures through mechanical exfoliation and focused-ion beam etching. Furthermore, we investigate the effect of geometrical confinement on changing the propagation direction of phonon polaritons in the forbidden direction. In addition, we explore the image polariton effect on propagation direction and tight in-plane focusing of phonon polaritons by introducing a perfect electric conductor beneath an α-MoO3 hyperbolic thin film. We observe that the confinement is greatly enhanced due to the image charge effect. These findings open avenues for chip-scale mid-IR nanophotonic devices and optical components with the ease of van der Waals integration.
Bio. Ethan Ray is a rising 3rd-year Materials Science and Engineering (MSE) major from Lexington Park, MD, studying at the Georgia Institute of Technology as a Stamps President’s Scholar. His research at GT is centered around the growth of 2D heterostructures and films for multiferroic devices. He is fascinated by device miniaturization, optimization of fabrication methods, and exploitation of novel functional material properties. Outside of research, Ethan mentors students as an MSE Ambassador and serves as President and Dance-Coordinator of the GT Filipino Student Association. His choreography has garnered over 30 million views online, displaying Filipino culture on a worldwide stage and cementing his mission to preserve and educate about the Philippine arts. Ethan plans to continue working towards materials research, education, and mentorship by pursuing a Ph.D. in MSE and becoming a professor.
- Ray was awarded a $1K travel grant at the capstone poster session.
Laura Weinstein - Biomedical Engineering, University of Delaware
Educational Institution: University of Delaware
List of Mentors: Dr. Mike King & Dr. Jason Zhang
Program: NSF REU
Research Project: Neutrophil-Mediated Transendothelial Delivery of E-selectin Liposomes for Targeting Inflammatory Sites
Poster: NSF REU Laura Weinstein Poster
Research Abstract: Nanomedicine is an expanding field that is revolutionizing translational medicine. Among the various nanoscale carriers, liposomal nanoparticles have gained significant attention due to their ideal size for robust transport within the environment of the body. Cell-mediated drug delivery harnesses the unique capability of nanoparticles to transport therapeutic cargo to specific destinations, such as tumors or inflamed tissues. To exploit this potential, our laboratory has developed a strategy for conjugating the protein E-selectin (ES) to the lipid-PEG shell of liposomes. This approach is advantageous as white blood cells possess ES ligands on their surface, enabling effective attachment of the liposomes to these cells. Subsequently, the liposomes can hitch a ride with white blood cells to target cancer cells in circulation or reach inflammatory sites, leveraging the immune system's natural response. Our investigation has focused on neutrophils as carriers for this cell-mediated delivery method, given their role as the body's first responders to infection or injury. By utilizing the protein Interleukin-8 (IL-8) as a signaling mechanism, we have successfully guided neutrophils to specific locations. Through comprehensive experimentation using TransWellTM migration chambers and identification through confocal imaging, we have demonstrated the ability of liposomes to attach to neutrophils and facilitate their migration across endothelial-like barriers via IL-8 signaling. These findings highlight the potential of liposome-neutrophil conjugates as efficient drug-carrying nanoparticle carriers, offering rapid and targeted relief in various medical conditions.
Bio. Laura Weinstein is a Eugene du Pont Scholar in the Honors College at the University of Delaware where she is studying biomedical engineering and nanoscale materials. At her home university, Laura is an undergraduate researcher in the Day Lab, where she researches polymeric nanoparticle synthesis for biomimetic cargo delivery. She presented her first poster in 2022 at the University of Delaware Summer Scholars Symposium as a part of the Center for Biomechanical Engineering Research (CBER) REU, and gave an oral presentation on her research as a Winter Research Fellow in January 2023. During her time at UD Laura has won the 2022 Ratcliffe Eco Entrepreneurship Foundation Switch Pitch and Innovation Sprint, 2022 and 2023 National Cyber Scholarship, and in 2023 was awarded the Biomedical Engineering Distinguished Sophomore Award. This summer Laura is grateful to be a part of the Vanderbilt Institute for Nanoscale Science and Engineering (VINSE) REU at the King Lab where she is researching cell-mediated drug delivery. After her graduation from UD, Laura plans to earn a PhD in bioengineering with a focus on nanomedicine and drug delivery.
- Weinstein was awarded a $1K travel grant at the capstone poster session.