REU Research Projects

Florence Sanchez, Civil and Environmental Engineering

The Sanchez lab focuses on the development of sustainable and more durable infrastructure materials with reduced environmental impact. One effort is the realization of novel, functionally graded concrete materials that can enhance the energy performance of buildings. This is achieved by engineering concrete at multiple length scales through the design of a hierarchy of internal structures inspired by nature and the incorporation of nano/micro-inclusions using extrusion-based 3D printing technology. The student will assist in the 3D printing fabrication of cement-based materials displaying a hierarchy of internal structures and patterns and investigations into the structure and mechanical and thermal performance of these novel materials. The student will gain firsthand experience in laboratory research, will be exposed to fundamental materials science and engineering of composite materials, and will develop skills in state-of-the-art analytical methods for the characterization of material microstructures.

Researcher Interests and Skills: This project is best suited for a student interested in material synthesis and characterization, 3D printing, and the applications of materials in civil engineering. Student must have completed at least one semester of chemistry and two semesters of a laboratory course.

Piran Kidambi, Chemical and Biomolecular Engineering

This project will focus on 2D materials that are one atom thick. The student will synthesize 2D materials using bottom-up self-assembly processes and develop transformative advances for energy, sustainability and environmental applications. The project will explore the ultimate paradigm in length scales probing single atom thick membranes with state-of-the-art experiments. Student will work closely with the PI, post-docs and graduate students in the lab.

Researcher Interests and Skills: The project is ideally suited for students interested in hands-on experimental research in nanotechnology.

De-en Jiang, Chemical and Biomolecular Engineering

The Jiang Group’s research focuses on computational chemical science and engineering, with a goal to achieve predictive modeling and design of functional materials and molecules for a sustainable society. Current research topics include computational nanocatalysis, simulations of separation media and processes, and first principles understanding of electrical energy storage and solid/liquid interfaces. One recent interest of our group is in novel anion-storage batteries. The project will focus on computational modeling of novel nanostructures (e.g., nanochannels) inside oxide-based electrode materials that allow reversible anion storage at high capacity. REU students working in the Jiang group would learn how to build atomistic models for electrode materials, how to carry out first principles calculations, and how to simulate atomistic processes of ion storage inside battery electrodes. Students will gain an appreciation for first principles calculations, materials modeling, battery chemistry, and electric energy storage.

Researcher Interests and Skills: This project is best suited for a student interested in computational nanoscience, materials chemistry, and battery research. Knowledge of Linux operating system, solid-state chemistry, and quantum mechanics is a plus.

Kalman Varga, Physics and Astronomy

The main activity of Kalman Varga's group is computational modeling and simulation of electronic and transport properties of nanostructures interacting with short strong laser pulses. The group is interested in time-dependent electron dynamics including Coulomb explosion, Petahertz electronics, attochemistry, time dependent band structure engineering, and ultrafast energy transfer processes. The group is also actively working on studying electron transport processes in nanostructures using novel computational tools.

Researcher Interests and Skills: Students with interest in computational nanoscience are encouraged to join us. Basics knowledge of quantum mechanics and programming is advantageous but we are glad to train student interested in this direction.

G. Kane Jennings, Chemical and Biomolecular Engineering
David Cliffel, Chemistry

Photosynthesis is the Earth’s 95 TW solar energy conversion process that dwarfs our rate of energy usage from fossil fuels by nearly an order of magnitude.  The Photosystem I and II protein complexes (PSI and PSII) are the drivers of photosynthesis in green plants.  These two proteins absorb mostly red and blue light and efficiently translate that light energy to a charge separation with over 1 Volt of potential difference across the thylakoid membrane.   These two powerful light-triggered events energize the Z-scheme of photosynthesis for the ultimate production of NADPH. While the overall efficiency of photosynthesis is low, the internal quantum efficiencies of PSI and PSII approach 100%. As such, researchers have long sought to extract and incorporate either the PSI or PSII protein complexes with electrodes to fabricate biohybrid solar cells. 

This project seeks to extract both PSI and PSII protein complexes from agricultural sources, modify them photoelectrochemically with metal nanoparticles or conducting polymers, and incorporate them both as the active elements in portable biohybrid solar cells. Thus, the project will introduce a sustainable approach to employ leafy agricultural byproducts for renewable energy. This project will combine PSI and PSII in the same pseudo-solid-state solar architecture to elevate cell potentials and recreate the Z scheme of photosynthesis within a biohybrid solar cell. The research addresses a particular challenge that has limited biohybrid solar cell performance—the wiring of the key reaction centers of PSI and PSII for direct electron transfer without resorting to expensive, yield-killing genetic modifications. This challenge will be surmounted by using the proteins’ active sites to photooxidize monomer or photoreduce metal salts and generate conducting protein-polymer or protein-particle conjugates. The asymmetry of these conjugates will provide chemical handles to orient the particles on an electrode of high surface area, and insulative backfilling around the proteins will greatly reduce charge recombination. The focus of this project is toward the materials interfaces and nanotechnology of these protein complexes.

Researcher Interests and Skills: This project is appropriate for a student who has an interest in investigating alternative energy and in characterizing materials and surfaces. Students should have completed general and organic chemistry courses.

Josh Caldwell, Mechanical Engineering

The infrared portion of the electromagnetic spectrum offers opportunities for non-contact measurements of temperature through the collection of thermal radiation, chemical vibrational fingerprinting for sensing and identification, lab-on-a-chip, environmental and remote sensing, and astronomical observations. However, the long free-space wavelengths of light in this spectral domain restrict such optical components to large form-factors limiting the ubiquitous implementation in commercial applications. Furthermore, most of the materials used are either opaque in the visible, hygroscopic, or only work over a very narrow band, while detectors typically require cryogenic cooling for efficient operation.

The field of nanophotonics seeks to identify schemes by which the wavelength can be compressed to deeply sub-wavelength dimensions, opening the door to implementation of more traditional semiconductor and dielectric materials, overcoming many of these challenges. However, despite this promise, we continue to uncover additional materials featuring novel optical properties. One specific class is highly anisotropic (low symmetry) crystals, such as van der Waals or so-called two-dimensional materials or wide bandgap semiconductors. One example is through confining and propagating infrared light through hyperbolic shear polaritons in monoclinic crystals, which results in highly directional propagation of light, with the direction tunable through changing excitation frequency (see figure).

An REU student working on this project will implement these materials for demonstrating such control of IR light propagation, using state-of-the-art 2D material transfer and lithography tools, along with learning to use advanced IR spectroscopic methods including Fourier transform infrared (FTIR) spectroscopy and microscopy, and the use of nano-optic probes such as scattering-type scanning near-field optical microscopy (s-SNOM) and nano-FTIR. To date, all seven undergraduate researchers (four of which were VINSE REU student alumni) of the Caldwell lab (since joining faculty in 2017) have seen their work published in a peer-reviewed journals, with this past summer’s REU student on track for a publication this Fall.

Researcher Interests and Skills: This project would be ideal for students interested in practical research in nanomaterial fabrication and optical characterization techniques. Ideally students should have completed at least one course covering basic optics, electromagnetics, solid-state physics/chemistry, materials science, or the optical properties of materials. Undergraduate research, especially in materials science, optics, spectroscopy, or experience with cleanroom use, are highly desired.

Janet Macdonald, Chemistry

The hematite (iron oxide) rock paintings of the Anishinaabe of the Northern US and Canada are often on exposed rock faces that suffer extreme weathering conditions. Spray paint graffiti on the same sites can be worn off within a year or two, yet the rock paintings persist. Unfortunately, the methods to make such paintings have been lost. What is the chemistry behind their indelibility? Can we use our knowledge of chemistry to re-discover the painting technique? Can lab reagents and conditions be translated to “natural” granite surfaces and naturally sourced materials? The researcher will develop experiments to test hypotheses put forward previously by anthropologists and by chemists (us!), by making their own pigments, varying the chemical formulation of the paint and testing their durability.

Researcher Interests and Skills: This project requires a minimum of senior level high school, AP or freshman chemistry and a strong interest in Chemistry or Materials Science. Students should have a secondary interest in Anthropology, History or Indigenous Studies. Given the nature of the project, interested researchers should be prepared to be respectful of cultures and religious beliefs to which they may not belong themselves.

Marjan Rafat, Chemical and Biomolecular Engineering, Biomedical Engineering

Despite the high risk of recurrence among TNBC patients, the steps of tumor cell reseeding and the roles of neutrophils and radiation-induced vascular damage remain unclear. Traditional in vitro models for studying mechanisms of cancer recurrence and metastasis (e.g., cell culture plates, organoids) fail to recapitulate the structure of vascular networks and do not incorporate flow, which is a key component of cell movement and transport of nutrients and secreted factors through the vasculature. The Rafat Lab is interested in establishing a more biologically relevant model of the mammary tissue vasculature in order to study the mechanisms of TNBC recurrence after radiation. An REU student in the Rafat Lab will have the opportunity to participate in experiments related to the to the fabrication and application of a two-channel microfluidic device to determine the impact of irradiated vasculature on neutrophil infiltration and tumor cell recruitment. The necessary platforms and protocols are well-established in the Rafat Lab. The REU students will be trained to independently conduct experiments. The project is best suited for a student interested in learning about cell-cell interactions in the tissue and tumor microenvironment through the design of biomimetic devices.

Researcher Interests and Skills: The Rafat Lab is accepting undergraduate students who would like to conduct research at the interface of engineering and cancer biology.

Craig Duvall, Biomedical Engineering

The Duvall lab develops and tests novel pH-responsive, "smart" polymeric carriers to be formulated as micelles and/or polymer drug conjugates for pharmaceutical applications. There are currently no mainstream clinical drugs consisting of intracellular-acting biologic macromolecules (i.e. peptides, proteins, and nucleic acids). These classes of molecules are too large and polar to diffuse across cell membranes, and if taken up by endosomal pathways, the predominant fates are lysosomal degradation or exocytosis. The pH-responsive polymers developed in the Duvall lab are optimized to respond to the discrete pH difference between the extracellular and endosomal environments to trigger biomacromolecular drug endosomal escape and cytoplasmic delivery. Current applications range cancer and regenerative nanomedicine. For the summer project, the student will implement microfluidic fabrication methods to form nanoparticles optimized for tumor penetration and anti-cancer therapeutic efficacy.

Researcher Interests and Skills: This project is best suited to students interested in nanomedicine. The summer project will expose students to living free radical polymerization, polymeric nanoparticle fabrication and characterization, and basic cell culture and molecular biology techniques.

Craig Duvall, Biomedical Engineering

The Duvall lab develops various "on demand" drug delivery systems that release drug or undergo phase changes based on environmental cues. Reactive oxygen species (ROS) are elevated, causing "oxidative stress", in many chronic inflammatory diseases. We are developing new classes of polymeric nanoparticles, microparticles, and hydrogels with ROS responsive/scavenging properties. These systems are tuned to release drug "on demand" - i.e., when ROS levels become elevated, the delivery system is triggered to release anti-oxidant drug. Many of these systems are also engineered to have inherent ability to sequester ROS from the local environment, which is therapeutically useful in order to limit inflammation-associated host tissue damage and promote disease resolution. Current applications range wound healing, breast cancer metastasis, and arthritis therapies. For the summer project, the student will learn methods for synthesis of ROS-reactive polymers, creation and characterization of particle formulations, and measurement of ROS scavenging activity and downstream therapeutic benefits.

Researcher Interests and Skills: This project is best suited to students interested in polymeric biomaterials and inflammation. The summer project will expose students to living free radical polymerization, polymeric nanoparticle fabrication and characterization, and basic cell culture and molecular biology techniques.

Jason Valentine, Mechanical Engineering

The Valentine group is focused on developing nanostructured materials, referred to as metamaterials, that have unique optical properties which arise from the structuring employed. The goal for this REU is the development of dynamic metamaterials that can have their optical properties adjusted in real-time using electrical, optical, or thermal modulation. The potential uses of these metamaterials are far ranging and include tunable optical elements such as lenses, optical displays, and tunable light sources. The REU student will work closely with the PI and a graduate student on this project and be responsible for fabricating and optically characterizing metamaterials with an emphasis on studying the time-varying properties including changes in transmission and reflection as well as the modulation speed.

Researcher Interests and Skills:  This project is best suited for individuals with interests in nanoscale optics and materials, nanoscale fabrication, and experimental optics techniques. The individual should have completed an electromagnetics course and experience with experimental optics and spectroscopy would be beneficial.

Sandra Rosenthal, Chemistry

The Rosenthal group is accelerating the development of sub-microscopic crystals of semiconductors, or quantum dots, by employing a newly developed characterization methodology. With this characterization methodology it is possible to determine the optical properties and atomic structure of an individual quantum dot. These quantum dots can be made to efficiently emit very pure colors. However, quantum dot systems that do not utilize toxic lead and cadmium lag far behind in brightness and stability. Directly correlating structure with performance will enable precise tuning of the quantum dot synthesis to produce optimal structures. This will pave the way for new display and lighting technologies and tools for biomedical applications such as drug discovery. REU students will have an opportunity to learn nanocrystal synthesis and to operate the advanced analytical FEI Tecnai Osiris TEM/STEM electron microscope as well as participate in single nanocrystal spectroscopy experiments.

Researcher Interests and Skills: This project is best suited for student interested in hands on experimental science involving the synthesis of colloidal nanocrystals and the associated characterization techniques of optical spectroscopy and electron microscopy.

Jamey Young, Chemical and Biomolecular Engineering

Extracellular vesicles (EVs) are cell-made particles that provide a natural mechanism of information and material transfer between cells. There is growing interest in large-scale production of EVs due to their potential use as carriers of drugs or other biomolecules to diverse cellular targets; however, the technology to mass-produce purified EVs with tunable and well-defined properties is still in its infancy. REU students will be recruited to work with senior members of our NSF Future Manufacturing project team to develop, test, and scale-up a flexible workflow for producing EVs from differentiated human induced pluripotent stem cells (iPSCs). Various biomaterials and cell encapsulation strategies will be examined for adapting adherent host cells to suspension culture, in order to maximize the volumetric rate of EV production in stirred bioreactors. In addition, REU students will contribute to the development of instructional “BioFab” modules that introduce digital fabrication and cell-based manufacturing concepts to Vanderbilt undergraduate students and high school students in the Metro Nashville Public Schools district.

Researcher Interests and Skills: This project is best suited for students interested in working at the interface between biomaterials and cell culture. They must also be interested in working in a team to develop instructional modules for undergraduate and high school students. The project involves a collaboration with the labs of Ethan Lippmann and John Wilson in Engineering, and Alissa Weaver in Cell and Developmental Biology. Development of “BioFab” modules will be led by Prof. David Florian.

Ethan Lippmann, Chemical and Biomolecular Engineering

This project focuses on developing and validating engineered models of the human brain. The Lippmann Lab has longstanding expertise integrating human stem cell-derived neural and vascular cells with biomaterials and engineered microdevices to build representative models of vascularized brain tissue. Cell phenotypes in biomaterials and devices are robustly characterized to see how closely they approximate native human brain, while devices are also continuously optimized to support these cell phenotypes and impart different stimuli.

Researcher Interests and Skills: The REU student will work with graduate students or postdoctoral fellows to test new cell culture devices and characterize cell phenotypes in these devices. No prior experience is needed, but the student will be expected to work effectively with his/her hands and be open to trial-and-error strategies for system optimization.

Josh Caldwell, Mechanical Engineering

Controllable spectral response and directionality of light from radiation sources are of critical interest within the mid-infrared (IR) range for waste heat recovery in energy storage, transportation, sustainability, as well as in chemical sensing, and imaging. Yet, the sources in the mid-IR are inefficient, bulky, expensive, and/or complex to design. On the other hand, metasurfaces - flat structured surfaces engineered to modify optical and electric functions - are promising platforms for tailoring optical properties. This allows thermal sources (e.g., old incandescent light bulbs) to be used as narrow band mid-IR radiation source with only heat as the input. Its compactness and simplicity provide significant advantages over the existing infrared light sources. In addition, highly anisotropic materials with exotic optical features in mid-infrared range provide viable candidates as a material for constructing such metasurfaces. An REU student working on this project will have the opportunity to take part in designing thermal metasurface devices, experience fabrication of the device using nanoscale lithography tools and nanoscale characterization of structure, optical response, and thermal behaviors. This will be achieved using tools such as Fourier transform infrared spectroscopy and nano-optical probes such as scattering-type scanning near-field optical microscopy, along with imaging microscopes such as scanning electron microscopes (SEMs) and atomic-force microscopes (AFM). The REU student will perform simulations for thermal design of the experimental setup and measure temperature of the device with thermocouples.of biomaterials.

Researcher Interests and Skills: This project is best suited for a student interested in heat transfer, nanofabrication, and material characterization. Student must have completed at least one semester of thermodynamics and two semesters of a laboratory course.

Mona Ebrish, Electrical and Computer Engineering

High electron mobility Transistors (HEMTs) are often grown on special wafers to meet the layers specifications and avoid lattice mismatch. Often these special wafers are not suitable for several electronics applications. In this project, the student will work with graduate students on isotopically etching a sacrificial layer to release the HEMTs from their native wafer. The sacrificial layer is often a Si layer that can be etched using XeF2 etcher. The transfer will take place using a state-of-the-art technique using a Micro-transfer printer tool at Ebrish Electron Devices Group (EEDG). The objective of the process is to successfully transfer a single device or a cluster of devices to a host wafer. The success of the process is gauged by the structural integrity of the transistor after the transfer as well as maintaining the same electrical characterization. REU student might focus on the etching and release processes of the project which involves some fabrication processes like photolithography steps at VINSE. The student might also focus on the transfer process at EEDG or the structural and electrical evaluation after the transfer. The area of focus will depend on the student’s skills and interest. All of the steps are novel and have the potential to be publishable in both peer reviewed journal and conference proceedings.

Researcher Interests and Skills: This project would be ideal for students interested in practical research in microelectronics fabrication and characterization techniques. Ideally students should have completed at least one course covering basic electronics including diodes, and transistors, or semiconductor physics. Undergraduate research, especially in semiconductor materials, electronics or experience with cleanroom use, are highly desired.

Xiaoguang Dong, Mechanical Engineering

Small-scale robots with an overall size less than one centimeter that can be wirelessly actuated, monitored and controlled, could revolutionize minimally invasive medical operations by allowing access to enclosed small spaces inside the human body and performing medical operations such as drug delivery, onsite biofluid pumping and biopsy. Wirelessly powered small-scale robots using stimuli-responsive material and mechanisms which can be actuated by magnetic fields are especially promising, as magnetic fields can penetrate most nonmagnetic materials such as biological tissue and induce relatively large magnetic forces and torques on the robot body for remote and precise actuation. Despite recent advances in this field, critical challenges still exist in creating intelligent miniature robots that could navigate through complex confined environments and demonstrate medical functionalities such as point-of-care diagnosis. This REU project aims at developing wireless soft robots for sensing tissue physiological properties. The REU student will work together with other lab members on the fabrication and test of flexible sensors based on various stimuli-responsive materials which will be integrated on miniature soft robots. Project outcomes include prototypes of the devices and a project report which could potentially be turned into a manuscript to be submitted to a proper journal or a top robotic conference such as RSS, ICRA, etc.

Researcher Interests and Skills: This project is best suited for a student interested in soft materials, flexible electronics, 3D printing, and the applications of materials in robotics and medical devices. The student should have skills on mechanical design and soft materials.

Richard Haglund, Physics and Astronomy

REU students working in the Haglund group will study the behavior of light in quantum materials with unusual optical and electronic functionalities, such as: vanadium dioxide nanostructures that transform from insulators to metals when irradiated by laser pulses; single-photon emission from two-dimensional crystals such as graphene-like hexagonal boron nitride; and optical harmonic generation in semiconductor-metal nano composites  Students will be able to fabricate thin films, crystals or nanostructures of quantum materials, study nonlinear optical phenomena with femtosecond lasers or characterize single-photon emitters for quantum information applications. For example, a REU student in the summer of 2024 used photoluminescence spectromicroscopy to locate and select single-photon emitters on hexagonal boron nitride nano sheets.

Researcher Interest and Skills: This project is well suited for a student interested in nanoscale material synthesis, spectroscopy, optical physics or quantum optics. A sophomore-level course in modern physics or optics provides sufficient background. Experience with any of the following is a plus for this project: optical spectroscopy, lasers, LabView instrumentation and software, computer simulations and software (e.g., Python, Matlab, Mathematica or C++), material characterization (e.g., X-ray diffraction, Raman spectroscopy) and microscopy.

G. Kane Jennings, Chemical and Biomolecular Engineering

Conventional thermal separations of water-solvent mixtures are energy intensive and costly. Aqueous polar solvent mixtures often present the challenge of azeotrope formation, requiring additional operations for separation. Membrane-based separations have emerged as an energy- and cost-efficient alternative separation method, with pervaporation as the prime candidate for separating these mixtures. Current polymeric pervaporation membranes are limited to a few commodity polymers that are often not molecularly designed for the intended separation, leading to low fluxes and mild selectivity. In addition, the synthesis of these polymers and fabrication of the membranes requires several liters of volatile organic solvent per gram of polymer deposited. This project combines polymer synthesis and deposition into one step to rapidly produce thin polymer films with a wide variety of compositions through a process we term spin-coating ring-opening metathesis polymerization (scROMP). The scROMP approach allows for thin polymer films to be fabricated in under 3 min on coupon supports using cyclic olefin monomers, Grubbs 3rd generation catalyst, and as little as half a mL of solvent per 35 cm2 of polymer selective layer. The scROMP method is being paired with molecular simulations to sample the wide array of potential compositions and accelerate the discovery of new polymer membrane selective layers. Polymers fabricated through scROMP are characterized by ATR-FTIR, stylus profilometry, SEM, contact angles, and GPC to determine properties as scROMP parameters and monomers are varied. The student participating on this project will learn to fabricate thin film composite membranes using scROMP, characterize them with various methods noted above, and measure component fluxes and selectivities of water-polar solvent mixtures. The student will vary polymer side chain composition and cross-linking density to determine the effects on glass transition temperature and membrane separation performance.

Researcher Interests and Skills: This project is appropriate for a student who has an interest in investigating sustainable energy and in characterizing polymeric materials and surfaces. Students should have completed general and organic chemistry courses.

Sharon Weiss, Electrical and Computer Engineering, Physics

Accurate and reliable detection of small, low molecular weight molecules is a major challenge for current sensor technology. The detection of these species is critical for applications including identification of disease biomarkers. The Weiss group is investigating the use of various silicon and nanoscale porous silicon optical structures as promising sensors for small molecule detection due to the strong light-matter interaction that takes place between the optical mode and target molecules of interest. Both on-chip and paper-based, smartphone-compatible sensor platforms are being explored. An REU student in the Weiss group will have the opportunity to participate in experiments and calculations related to the design, fabrication, and characterization of silicon-based sensors. Necessary fabrication and measurement systems, as well as simulation infrastructure, are well-established in the Weiss lab. The REU student will be trained to independently conduct experiments. This project is best suited for a student interested in optics and nanomaterials.

Researcher Interests and Skills:  The REU student must have completed at least one semester of physics and one semester of chemistry.

Justus Ndukaife, Electrical Engineering

The Ndukaife Research group conducts research at the interface between nanophotonics and microfluidics to develop new lab-on-a-chip devices for trapping, manipulation, sorting and sensing of nanometric objects and biological molecules, which are too small to be trapped by the conventional optical tweezers that was recently recognized with a 2018 Physics Nobel Prize. For this particular project, we are interested in developing and characterizing novel optical nanotweezers that can trap and manipulate very small objects that are at least a thousand times smaller than the thickness of the human hair using light and electric voltage.

Researcher Interests and Skills: This project is best suited for a student interested in nanotechnology and optics. Students should have completed at least general chemistry with a corresponding lab course.

Sharon Weiss, Electrical and Computer Engineering, Physics

Silicon has traditionally been associated with being the most favorable material platform for most modern microelectronics technologies due to its electronic properties, compatibility with lithographic patterning, and earth abundance. However, silicon is also a favorable material platform for supporting light propagation, and silicon photonics is now considered to be the leading platform to achieve faster data transfer speeds on chip and a promising platform for quantum information science. The Weiss group is investigating on-chip silicon photonic components with subwavelength features and extremely strong electric field enhancements, which may lead to the next generation of on-chip photonic devices with ultrafast modulation speed, low power, and small footprint. An REU student in the Weiss group will be trained to independently carry out both experiments and simulations related to the design and characterization of advanced silicon nanophotonic components.

Researcher Interests and Skills: This project is best suited for a student interested in optics and semiconductors. The REU student must have completed at least two semesters of physics. Knowledge of electromagnetics would be helpful, but not required.

Jason Valentine, Mechanical Engineering

The Valentine group is focused on developing nanostructured materials with tailored electromagnetic properties at optical frequencies, specifically for applications in photovoltaics, detectors, and other more exotic devices such as invisibility cloaks. These nanostructured materials, referred to as metamaterials, can be engineered with unique optical properties due to the type of structuring and constituent materials employed. The purpose of this summer research experience is to implement metamaterials as pre-filters for image processing systems. For instance, metamaterials can be designed to perform derivatives and act as spatial filters, off-loading these operations from the digital system. Ultimately, this allows the digital system to operate faster and consume less power while also taking advantage of the unique design freedoms associated with metamaterials. The REU student will work closely with the PI and a graduate student on this project and be responsible for designing and optically characterizing metamaterials for various image processing tasks.

Researcher Interests and Skills: This project is best suited for individuals with interests in nanoscale optics and materials, nanoscale fabrication, and experimental optics techniques. The individual should have completed an electromagnetics course and experience with machine learning systems will be beneficial.

Leon Bellan, Mechanical Engineering

In the human body, vascular resistance is regulated by non-capillary microvessels which autonomically contract or dilate in response to appropriate biochemical stimuli. This process is critical to ensuring appropriate local pressure-flow relationships in tissue such that metabolic needs are met. Engineered microvasculature, however, is currently unable to replicate this critical functionality. This is because engineered microvasculature currently does not incorporate circumferentially aligned smooth muscle cells (SMCs) capable of regulating vessel lumen diameter. The goal of this project is to use 3D printed sacrificial templates to pattern microvascular channel networks in hydrogels and culture SMCs on the channels walls, and then induce appropriate SMC behavior and architecture using the cyclic wall stretch that results from pulsatile flow in these compliant matrices. Cells will then be exposed to various stimuli and their ability to modulate vessel lumen diameter will be characterized. This interdisciplinary project will also provide participating students with valuable materials processing and cell culture skills, and expose students to the challenges and excitement of novel biomaterials micropatterning techniques. Students will work with the PI, and graduate students and postdoctoral researchers in the Bellan lab, as well as with collaborators in other departments at Vanderbilt University.

Researcher Interests and Skills: This project is appropriate for students who are interested in hands-on experimental work and would like to learn more about biomaterials, flow characterization in a biomedical context, and 3D printing.. Experience with programming, electronics, biomaterials, or cell culture techniques would be beneficial but is not required.

John T. Wilson, Chemical and Biomolecular Engineering

The Wilson ImmunoEngineering Lab (www.immunoengineeringlab.org) focuses on the treatment and prevention of disease through the design of nanoscale drug delivery systems that modulate the immune system. A major focus of our work is the design of protein, polymer, and lipid-based nanocarriers to enhance the intracellular delivery of the key components of vaccines and cancer immunotherapies. The summer research project will focus on design, testing, and optimization of novel drug delivery platforms for modulation of the immune system. REU students working in the Wilson group have the opportunity to learn a diversity of skills and concepts, potentially including polymer synthesis, colloidal self-assembly, nanoparticle characterization, protein engineering, bioconjugate chemistry, and immunobiology.

Researcher Interests and Skills:This project is best suited for a student interested in materials synthesis and characterization and the applications of materials in biology and medicine. Student must have completed three semesters of a laboratory course.

Janet Macdonald, Chemistry

Metal sulfide nanocrystals have been a cornerstone of nanotechnology research: as examples Quantum dots of CdS, PbS and ZnS; graphene-like MoS₂ and lithium ion storing cobalt sulfides. As we seek new nanoscale materials for their electronic, catalytic, thermoelectric and optical properties we need to mine farther and farther reaches of the periodic table. The geologic record tells us there are many untapped materials: there are nine known iron sulfides, four cobalt sulfides, seven nickel sulfides and ten copper sulfides. As physical and chemical properties depend on the identity and the specific arrangement on atoms in space, each of these phases has their own set of potentially revolutionary properties for any number of applications from display technology, catalysis, batteries, non-linear optics and even cancer treatment.

Some of the aforementioned metal sulfides have never been prepared as nanocrystals before, as to date, our syntheses have been mostly serendipitous. The community of chemists do not have the level of synthetic skill or knowledge of how to tweak a “failed” reaction to select for one crystal phase over another. In this project we will use libraries of organosulfur reagents to tease out how kinetics and decomposition mechanism each play a role in the phase selective synthesis of transition metal sulfides. Our goal is to synthetically traverse the full phase space of metal sulfides.

Researcher Interests and Skills: This REU will be conducting synthetic experiments at high temperatures using Schlenk techniques, and will learn to use and analyze their products with X-ray diffraction as a routine technique. Transmission electron microscopy on promising samples will be performed with the aid of a graduate student. Given the synthetic rigors of the project, organic chemistry with a laboratory component is a minimum requirement, or similar synthetic laboratory experience.  

Lauren Buchanan, Chemistry

The Buchanan group focused on the use of 2D infrared spectroscopy to study protein structure and dynamics. In this project, we are interested in determining the structure of nanoparticle-bound proteins. For proteins, structure determines function; thus, for biomedical applications of nanomaterials to be viable, it is crucial to understand precisely how protein-nanoparticle interactions alter protein native structure. While it is well-established that global structural changes do occur upon binding to a nanoparticle surface, no one has managed to localize structural rearrangements to specific regions of the protein or determine the mechanisms by which nanoparticles affect protein aggregation. Using 2D IR spectroscopy and isotope labeling of proteins, we can achieve residue-level structural resolution of these complex systems and observe transient species that are inaccessible by conventional methods.

Researcher Interests and Skills: This project is best suited for students interested in physical or bioanalytical chemistry. Students should have completed at least general chemistry with a corresponding lab course.

Deyu Li, Mechanical Engineering

The Li group explores energy transport at nanoscale, which provides critical knowledge for various engineering applications including microelectronic device thermal management, novel energy converters, and powerful cooling technology for buildings. Currently we are pursuing super-efficient radiative cooling strategies via a type of novel energy carriers, phonon polaritons, which result from coupling between infrared photons and atomic vibrations in polar materials. Our recent research results indicate a strategy to efficiently launch phonon polaritons to a number density that is higher than the corresponding equilibrium value, which could lead to super-Planckian far-field radiation. The REU student will work with a Ph.D. student/post-doc to conduct experimental measurements of thermal transport mediated by non-equilibrium phonon polaritons and understand/demonstrate its impact on thermal radiation.

Researcher Interests and Skills:This project is best suited for a student who is interested in experimental work exploring energy transport through nanostructures. The student should have completed college physics courses and taken some engineering classes.

Scott Guelcher, Chemical and Biomolecular Engineering

The Guelcher group focuses on the design and development of synthetic biomaterials for soft and hard tissue engineering and drug delivery. Examples include delivery of biofilm dispersal agents to prevent infection and accelerate healing of contaminated bone wounds, and delivery of Wnt signaling inhibitors to enhance cutaneous wound healing. REU students working in the Guelcher group would learn the fundamentals of biomaterials synthesis and drug delivery, and perform experimental measurements using both in vitro and in vivo models. For example, previous undergraduate researchers in the Guelcher lab have measured the ability of novel biomaterials to support osteoblastic differentiation and the release kinetics of antibiotics from polymeric scaffolds. Each student initially works very closely with the PI and a graduate student or postdoctoral associate in the group, with the best students becoming essentially independent by the time they leave the lab.

Researcher Interests and Skills: This project is best suited for a student with interests in drug delivery and cell culture. The student should have completed a laboratory course, and courses in organic chemistry and biology would be helpful. The student will work in an inter-disciplinary environment with chemical engineers and molecular biologists to develop new therapies for regeneration of bone and soft tissue.

William Fissell, Nephrology and Hypertension

Many cell types in the body are exposed to fluid flow: endothelial cells, lung cells, and kidney cells when growing in vivo, but cell culture techniques for prolonged in vitro culture are often static. Static culture limits mass transport of respiratory gases and nutrients; furthermore some cell types require mechanical forces to cue differentiation. Microfluid systems are available for cell culture in vitro, but typical growth area and number of cells are small. In larger systems pr in systems grown for longer periods of time, spontaneous outgassing of nitrogen bubbles can occur. Most microfluid systems exist in a length scale regime where surface forces are similar to inertial forces; as a consequences bubbles can stop flow in a microchannel or mechanically traumatize a cell in the channel.

Many techniques exist for de-airing fluids and for separating out bubbles from relatively small channels at low flow rates. We require a technique that can continuously separate bubbles as small as 20 microns from flow rates up to 50 ml/min for artificial organ development.

Researcher Interests and Skills: This is best suited to a student who has an interest in cell biology and microfluidics. Students will devise perfusion systems and assess the effects on cell health, including per, western blot, and functional assays. Familiarity with soft prototyping and labview may be helpful.

David Cliffel, Chemistry

In a collaboration between the Cliffel and Jennings Research groups, we investigate the use of Photosystem I (PSI) in a non-biological setting to efficiently convert solar energy into electricity or fuels. By taking this nano-machinery found in the process of photosynthesis and integrating with different electrode materials, we aim to both increase the efficiency and decrease the cost of modern solar conversion techniques. REU students working with the Cliffel and Jennings research groups learn the fundamentals of surface modification, surface analysis, and electrochemistry. For example, previous REU students have worked on projects integrating and analyzing PSI with carbon-based electrodes, and measured the resulting photocurrents of these systems. Typically 2 students work closely with and graduate students in both the Cliffel and Jennings lab.

Researcher Interests and Skills: This project is best suited for a student interested in chemistry or chemical engineering. Students should have completed at least general chemistry with a corresponding lab course.