Projects

Each of the research projects below centers around the creation, characterization and modeling of nanostructured materials for  biological and energy applications. Discovering, designing, characterizing and applying nanomaterials are national research priorities because of the crucial importance of nanomaterials in solving the looming energy crisis, their growing application in medicine (in bio-mimetic and bio-compatible materials), and in post- silicon nanoelectronics. With such a wide range of project areas to choose from students will be assisted as needed in choosing a suitable project that matches their interests.

Applying Diamond or Related Materials to Make Advanced Devices

"Applying Diamond or Related Materials to Make Advanced Devices"
Jim Davidson and Weng Kang, Electrical Engineering

This project will apply the technology established in our nanooelectronics laboratory to create active electronic, electrochemical and NEMS (Nano-electro Mechanical Systems) devices out of diamond or similar materials such as carbon nanotubes. Diamond can be used to make devices that are biocompatible, faster, stronger, more sensitive and even cheaper than other approaches. The specific objectives of the program are to:
- Support design of D-NEMS and other device configurations
- Suggest setup and perform tests that support evaluation of diamond/nanocarbon response to stimulus
- Support microscopic analysis of varied diamond layer combinations
 
Researcher Interests and Skills: This project is best suited for a student interested in nanoelectronic materials and processing, device fabrication, and characterization. Student should have completed a laboratory course and enjoy working in a laboratory setting.

Carbon Nanotube-Biobybrids and Drug Delivery

"Carbon Nanotube-Biobybrids and Drug Delivery"
  Yaqiong Xu, Electrical and Computer Engineering

Carbon nanotube (CNT)-biohybrids are organic-inorganic hybrid nanostructures composed of biomolecules (e.g. DNA, RNA, enzymes, and antibodies) and inorganic CNTs. These hybrid materials tend to encompass the strength of each material and offer novel structural and functional properties. CNTs exhibit unparalleled electronic, thermal, and mechanical properties, robust electrochemical stability, as well as high surface to volume ratio. All these unique properties make CNT-biohybrids one of the most promising materials that could transform technologies such as drug delivery, diagnostic imaging, as well as chemical and biological sensing. Undergraduates participating in this project would learn how to synthesize CNTs, how to prepare CNT-biohybrids, how to characterize CNT-biohybrids. Typically 2-3 students work closely with a graduate student or a postdoctoral associate.

Researcher Interests and Skills: This project is best suited for a student interested in synthesis, fabrication, and characterization.

Cellular Dynamics

"Cellular Dynamics"
David Piston, Molecular Physiology and Biophysics, Physics, Biomedical Engineering

The Piston Lab studies the intracellular and intercellular dynamics of pancreatic islets, which are groupings of endocrine cells responsible for the regulation of blood glucose levels.  The most abundant cell type within islets, the β-cell, secretes insulin in response to increased concentrations of extracellular glucose.  Stimulatory levels of glucose result in increased metabolism and electrical activity, which leads to a rise in intracellular Ca2+.  Islets exhibit synchronous Ca2+ oscillations that cause pulsatile secretion of insulin.  This synchronized electrical activity is a product of the gap junctions which couple β-cells together.  The second most abundant cells in islets are the glucagon secreting α-cells.  These cells are highly related to the β-cells, and isolated α-cells secrete glucagon in response to increased glucose.  However, in the islet and in the live animal, glucagon secretion decreases as glucose rises.  We now know that synchronous β-cell function is critical for changing the α-cell response to glucose. To elucidate the mechanisms of cell coupling underlying β-cell to α-cell communication, we use quantitative live cell microscopy to measure single cell parameters within intact islets exposed to spatially heterogeneous levels of glucose.  The resulting data are fit using computational models of the islet signaling dynamics.  Much of our data is contradictory to the current mathematical models, so we are continually modifying the model to better fit the observed islet physiology.

Researcher Interests and Skills: This project is best suited for a student with good quantitative measurement and analysis skills, and some experience with computer programming.  Familiarity with MatLab would be a plus, as would some experience with wet bench laboratory techniques.   

Computational Soft/Hard/Bio Materials

"Computational Soft/Hard/Bio Materials"
Clare McCabe, Chemical and Biomolecular Engineering

The McCabe group focuses on the use of molecular modeling to predict the properties of nanostructured soft materials.  Examples include understanding the ability of organic (carbon nanotubes) and inorganic (polyhedral oligomeric silsesquioxanes or POSS molecules) nanoscale building blocks to cross lipid bilayers, a process relevant to the nanotoxicology of these NBBs, and studying the nanoscale self-assembly of lipids to understand skin barrier function. REU students working in the McCabe group learn the fundamentals of molecular modeling and perform and analyze simulations run on local machines (on both CPUs and GPUs), as well as those at national supercomputing centers. For example, previous REU students in the McCabe group have investigated the solubility of carbon nanotubes in octanol and water solvents to aid in the determination of octanol-water partition coefficients, studied the effect of chain length on the self-assembled nanoscale structures formed from complex lipid mixtures, and investigated the nanotribology of monolayer coatings.  Typically 2 - 3 Students work closely with the PI and a graduate student or a postdoctoral associate in the McCabe group.
 
Researcher Interests and Skills:This project is best suited for a student interested in computational work. Students should have completed at least one college level programming course (such as matlab, java, fortran, or c++) or equivalent experience.

Decoding Neuronal Network Using Nanosensor

"Decoding Neuronal Network Using Nanosensor"
Qi Zhang, Pharmacology

Recent development in nanotechnology has revolutionized the biomedical research, particularly in visualizing biological molecules and structures with unprecedented accuracy. We are interested in developing nanomaterial-based optical detection platform to investigate the dynamic and plastic nature of neuronal network in mammalian central nerve system, which will shield light on the pathogenesis of many neurological disorders like Alzheimer's disease. Taking advantage of the unique size and physical properties of nanomaterials like quantum dots and graphene, we focus on high-speed high-throughput imaging of subcellular structures and protein complexes residing at neuronal synapses, the elementary transistors for neural network. In particular, we integrate such new techniques with reliable electrophysiological methods like whole-cell patch-clamp recording to decode the mechanism underlying information processing in the central nerve system. Undergraduate in physics or chemistry related majors are welcome to work with graduate students and postdoctoral fellows on independent or collaborative projects. They will be trained on nanofabrication, live-cell imaging, electrophysiology and data analysis. 

Researcher Interests and Skills: This project is best suited for students interested in interdisciplinary project involves chemistry, physics, molecular biology and neuroscience. Students must have completed one laboratory course and at least one college level biology course (such as cell biology) or with equivalent experience.

Development of New pH-responsive Polymers for Drug Delivery

"Development of New pH-responsive Polymers for Drug Delivery"
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.
 
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, polymer characterization, and basic cell culture and molecular biology techniques. 

Energy Storage and Conversion Systems

"Energy Storage and Conversion Systems"
Cary Pint, Mechanical Engineering

The Pint group focuses on the next-generation design of energy systems that have promise for integration, high energy density, and eventual replacement of fossil fuel energy resources.  Some examples of research efforts in the Pint lab focus on solid-state materials design for metal-air and metal-ion batteries using atomic layer deposition, and the chemical vapor deposition growth of nanostructured materials, including nanocarbons and nanostructured semiconductors, relevant for architectures in solar devices and batteries.  Participating REU students will obtain valuable experience at the intersection of two dynamic fields: the atomic-level engineering design of materials relevant for energy applications, and testing and characterization of batteries that have promise as next-generation energy carriers for portable electronics to transportation systems.  Students will work closely with the PI, graduate students in the Nanomaterials and Energy Devices Laboratory, and have the opportunity to interface with collaborators in industry and abroad to experience the dynamic environment in the energy sciences. 

Researcher Interests and Skills:  The project is geared for students who can participate in hands-on experimental research in materials fabrication and energy device testing.  Given the highly interdisciplinary nature of this effort, students with interests covering a wide variety of science and engineering disciplines are sought.

Engineering Photothermal Energy Conversion in Plasmonic Nanostructures

"Engineering Photothermal Energy Conversion in Plasmonic Nanostructures"
Jason Valentine, Mechanical Engineering

Surface plasmons are electromagnetic waves that travel on the surface of a metal through electron oscillations. These highly localized waves are commonly used to concentrate and manipulate electromagnetic energy for applications such as sensing, optical antennas, and imaging. However, surface plasmons suffer from absorption loss in the form of Joule heating which has, until recently, been viewed as a parasitic loss. In this work we take advantage of this effect, focusing on engineering the propagation of surface plasmons to create efficient optically induced nanoscale heat sources. This emerging field, deemed thermoplasmonics, and has applications in chemical catalysis, solar energy conversion, and heat-assisted magnetic recording.
     Currently, there are two major challenges in the field of thermoplasmonics. One is to design and realize more efficient plasmonic nanoheaters and the other is to experimentally measure their temperature. The goal of this project is to realize advances in both of these areas by designing novel nanoscale thermoplasmonic antennas (Fig. 1) while also developing a new thermal microscopy method capable of measuring nanoscale temperature profiles.  The REU student will be responsible for fabricating thermoplasmonic antennas as well as characterizing their temperature with a new thermal microscopy technique based on thermographic phosphors which have a temperature dependent lifetime. In accomplishing the project, the student will gain experience in electron beam lithography, material deposition, spectroscopy, and thermal microscopy. The REU student will work closely with the PI and a graduate student on this project.
 
Research Interest and Skills:  This project is best suited for individuals with interests in nanoscale optics, heat transfer, materials, and experimental optics. Past experience in these areas would be beneficial but is not necessary. 

Metamaterials

"Metamaterials"
Richard Haglund, Physics and Astronomy

Students working in the Haglund group will study the optical properties of switchable metamaterials, composed of metal nanostructures arranged in geometrically regular arrays and vanadium dioxide (VO2) thin films. The unusual properties of metamaterials include perfect focusing, negative refractive index and even “cloaking” - that is, becoming invisible at certain wavelengths. The illustration in Figure 1 is taken from experiments and calculations carried out by an undergraduate student in the summer of 2009 on gold split-ring resonators (SRRs). Panel (c) shows how a particular spectral feature is correlated with electric-field oscillations calculated from a simulation with the LumericalTM Maxwell equation solver for the SRR. In addition to bare metal SRRs the group is also fabricating hybrid Au::VO2 SRRs. Because the metal optical response - called a surface plasmon - depends on the local dielectric function, the metamaterial response switches in wavelength as the VO2 undergoes its characteristic insulator-to-metal transition.
 
Researcher Interest and Skills: This project is well suited for a student interested either in nanoscale materials physics or optical physics.  Students should have completed at least a sophomore-level course in either modern physics or optics.  Experience with any of the following is a plus for this project:  optical spectroscopy, lasers, LabView instrumentation software, computer simulations and software (e.g., Matlab, Mathematica or C++).

Nanocrystal Sensitized Solar Cells

"Nanocrystal Sensitized Solar Cells"
Sandra Rosenthal, Chemistry

Semiconductor nanocrystals with large extinction coefficients and tunable absorption spectra, are a light harvesting element in solar cells. If a nanocrystal-nanostructured solar cell is properly designed (Figure 3) electrons and holes travel to the electrodes in separate media, eliminating recombination losses. The foundation of success of this all-solid-state, all-inorganic technology is quality nanocrystal synthesis, solar cell fabrication, and solar cell testing. Undergraduates participating in this project (with the guidance of graduate students) would learn how to synthesize nanocrystals, how to fabricate photovoltaics, and how to characterize photovoltaic devices. Students would gain an appreciation of Generation 3 solar cells and study alternative energy technologies.
 
Researcher Interests and Skills: This project is best suited for a student interested in synthesis, device fabrication, and characterization. Student must have completed three semesters of a laboratory course.

Nanofiber-Based Membranes and Electrodes for Hydrogen/Air Fuel Cells

"Nanofiber-Based Membranes and Electrodes for Hydrogen/Air Fuel Cells"
Peter Pintauro, Chemical and Biomolecular Engineering

The heart of a hydrogen/air proton exchange membrane fuel cell is the membrane-electrode-assembly, where catalytic precious metal powder electrodes are attached to the opposing surfaces of a cation-exchange membrane. The membrane in such a device has three functions: (1) it physically separates the positive and negative electrodes, (2) it prevents mixing of the fuel and oxidant, and (3) it provides pathways for proton transport between the electrodes. Thus, fuel cell membranes must exhibit a high ionic conductivity, with zero electronic conductivity, controlled water swelling, and good thermal/mechanical/chemical stability in the wet and dry states. Similarly, for cost-control reasons, the Pt-containing anode and cathode in a fuel cell, where hydrogen is electrochemically oxidized and oxygen is reduced, must have a composition and structure that maximizes catalytic activity and long-term durability/performance. In this project, the use of nanofiber electrospinning techniques to fabricate proton conducting fuel cell membranes and high performance Pt/C cathodes will be investigated.  Methods for membrane and electrode fabrication will be studied and structure/property data will be collected. The new nanofiber-based membranes and electrodes will also be tested in a fuel cell where power output and durability will be assessed.

Nanofluidics

"Nanofluidics"
John Wikswo, Physics, Biomedical Engineering, Molecular Physiology and Biophysics

 REU students in the Wikswo group would be trained in an array of experimental and analytical techniques, including AutoCAD, photolithograpy, microfabrication, cell culture, microscopy, image analysis, and presentation skills, while working on ongoing nanoscience projects. An example would be the use of nanofluidics in the study of quantum dot aggregation and dynamics using spectrally and temporally resolved measurements of trapped or isolated nanoparticles in a imaging system built around coPI Rosenthal's frequency-doubled femtosecond Ti-sapphire laser. The system provides a user-configurable four-beam pulse-interleaved excitation and piezo sample positioning for isolation/trapping, a back-illuminated EM-CCD camera for high-sensitivity wide-field imaging, a prism spectrometer and fast-kinetics mode for time-resolved emission spectra, and a single-photon avalanche diode for single-molecule detection, sub-nanosecond lifetime measurements, and fluorescence correlation spectroscopy. Student projects could, for example, include development of new microfluidic devices for sample manipulation, and the study of the properties of white-light nanocrystals.
 
Researcher Interests and Skills: skills that are valued are experience in designing, building, and debugging electronic, mechanical, optical and microfluidic systems; image processing, computer and microprocessor programing. 

Nanomaterial Sensors

"Nanomaterial Sensors"
Sharon Weiss, Electrical 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 biotoxins and drug discovery. The Weiss group is investigating the use of porous silicon waveguides and diffraction gratings as promising sensors for small molecule detection due to the large number of molecules that can be concentrated within the enormous internal surface area of the porous silicon matrix. An REU student in the Weiss group will have the opportunity to participate in both experiments and calculations related to the design, fabrication, and characterization of porous silicon sensors. Porous silicon fabrication and measurement systems are well-established in the Weiss lab, and the REU student will be trained to independently conduct experiments. The REU student will also have access to in-house transfer matrix analysis code and commercial RSoft optical modeling software to understand how the interaction of the electric field with biomolecules affects the sensitivity of detecting those molecules in the porous silicon sensors. This project is best suited for a student interested in photonics, nanomaterials, and chemistry.

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

Nanomaterials for High Performance Cementitious Composites

"Nanomaterials for High Performance Cementitious Composites"
Florence Sanchez, Civil and Environmental Engineeering

The Sanchez group examines how new materials being developed by the nanoscience community can contribute to improving the long-term performance and durability of cement-based materials. The high specific strength, good chemical resistance, and electrical and thermal conductivity of carbon nanofibers/nanotubes (CNFs/CNTs) make them attractive for use as cement reinforcement in the development of composites with superior mechanical and functional properties. An REU student working in the Sanchez group will assist in investigations into the structure and performance of these novel materials. The work will primarily consist of the evaluation of the effect of the CNFs/CNTs on the performance of the composite, including the effects of dispersing methods, CNF/CNT loading, and the addition of supplementary cementitious materials.  Processes occurring at the reinforcement-cement interface will be examined. Advanced physical and chemical characterization techniques (e.g., SEM-EDS and thermal analysis) of reinforcement-cement interactions in conjunction with equilibrium sorption studies with cement extract solutions will be used to investigate the binding affinity of the cement phases with the CNFs/CNTs. The processing-microstructure-dispersion and dispersion-property relationships will be investigated. The student will work under the supervision of Sanchez and a graduate student. 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 the operation of state-of-the-art analytical equipments. 

Researcher Interests and Skills: This project is best suited for students interested in materials synthesis and characterization with applications to civil infrastructure. Students must have completed at least one semester of chemistry and one laboratory course.

Nanomaterials for Programmed Delivery Triggered by Disturbed Cardiovascular Flow

"Nanomaterials for Programmed Delivery Triggered by Disturbed Cardiovascular Flow"
  Hak-Joon Sung, Biomedical Engineering

The overarching goal of this study is to address this unmet need through development of a multifunctional nanomaterial that can navigate, detect, and release therapeutics in response to disturbed, oscillatory flow. We will fabricate ultrasmall, superparamagnetic iron oxides (USPIOs) and surface functionalize them with novel peptide-polymer conjugates.  The polymeric component enables water dispersibility and provides the carrying capacity for therapeutic drugs.  The iron oxide core provides magnetic resonance (MR) image contrast for in vivo localization co-registered with the anatomical information necessary to characterize the region of disturbed flow.  The resulting library of targeted, therapeutic nanomaterials will be functionally assessed in cone-and-plate viscometer studies and a mouse partial carotid ligation model (PCL) through quantitative, engineering-based analysis.
 
Researcher Interests and Skills:This project is best suited for a student interested in nanomaterials and peptide engineering. Students should have completed at least three semesters of a laboratory course.

Nanoparticle Synthesis for Green Energy Applications

"Nanoparticle Synthesis for Green Energy Applications"
Janet Macdonald, Chemistry

The Macdonald Laboratory is a nanoparticle synthesis group. We are especially interested in preparing new nanoparticles and multicomponent hybrid nanoparticles for green energy applications, such as particles that will undergo photocatalytic water splitting, or new nanoscale electrocatalysts to be used in solar cells. As an example of an undergraduate project, one student worked on new ways to modify surface capping ligands on the particles to make the nanoparticles water-soluble — an important step before studying water splitting.  Another previous REU student prepared copper oxide nanoparticles of different shapes, imaged them with scanning electron microscopy, and studied how their shape effected the photocatalytic properties. Typically, undergrads work closely with the PI and one of the graduate students or post docs in the group as mentors but are typically given independent research projects.
 
Researcher Interests and Skills: Students should be interested in chemical synthesis and working with their hands. To be prepared to work in a wet chemistry lab, students should have completed two semesters of general chemistry (or equivalent) and at least one course (with a lab component) of organic chemistry.

Nanophase Temperature Sensors

"Nanophase Temperature Sensors"
Greg Walker, Mechanical Engineering

The Walker group has manufactured nanoscale crystals whose florescence provides a unique way to measure temperature remotely. As such their work has important applications in aerospace diagnostics and micro scale thermal imaging. The bulk phases of these materials are often called thermo graphic phosphors (TGP), and their fabrication is time consuming and costly. Moreover, the properties of the material from traditional fabrication techniques are difficult to control. Instead, the Walker lab uses combustion processes to generate large volumes of materials quickly and easily. The product is often crude in terms of precise control of nanocrystalline properties, but the material is superior in terms of temperature sensitivity and can be tuned by changing stoichiometry and doping. REU students will test the properties of the nanocrystalline products. By varying substitutional species, the quenching temperature and temperature-dependent decay can be characterized. In addition, students will study the morphology of the products using SEM and TEM to learn how nanostructure can affect bulk properties of the TGPs. Each student will work closely with the PI and a graduate student.
 
Researcher Interest and Skills: This project is best suited for a student interested in ceramic materials synthesis and energy applications. Beneficial skills include spectroscopy.

Nanophotonics for Cancer Imaging

"Nanophotonics for Cancer Imaging"
Melissa Skala, Biomedical Engineering

A variety of nanoparticles can be used to achieve molecular contrast in cancer through their unique interactions with light.  Our lab is interested in characterizing and exploiting novel nanoparticles for optical molecular imaging in pre-clinical models of cancer including cell culture and animal-based experiments.  These methods have the potential to unveil the mysteries of acquired and innate drug resistance in tumors, therefore optimizing the process of cancer treatment.  Undergraduates participating in this project would learn how to synthesize, characterize and functionalize nanoparticles, and would use optical imaging technologies including multiphoton microscopy and optical coherence tomography to image these particles in biologically relevant tumor models. Undergraduate students typically work closely with the PI and a graduate student or a postdoctoral associate in the group.
 
Researcher Interests and Skills: This project is best suited for a student interested in working with biological samples (cells, animal models), experimental optical imaging techniques, and the synthesis and characterization of nanoparticles. Student must have completed a laboratory course, and are encouraged to have taken physics with an optics module.

Nanoscience for Energy and Biotechnology

"Nanoscience for energy and biotechnology"
Rizia Bardhan, Chemical and Biomolecular Engineering
 

Research efforts in the Bardhan group are focused on interdisciplinary nanoscience, with the convergence of multiple disciplines: engineering, material science, chemistry, physics, and biomedicine. We combine both wet-chemistry and nanofabrication techniques to engineer nanostructures, and employ cutting-edge tools such as molecular spectroscopy, electrochemistry, and super-resolution imaging to characterize nanomaterials with the ultimate goal of utilizing these materials to solve important global challenges – energy and sustainability and human health. A few examples of research projects that REU students would be involved in would be synthesis of metal and metal oxide nanostructures and exploring their optical and catalytic properties, using these nanostructures for biomedical sensing or photocatalytic water splitting to produce hydrogen.  Each REU student working in the Bardhan group will learn the fundamentals of plasmonics and nanophotonics which forms the foundation of the research group. Additionally students will also learn about nanomedicine, and energy conversion and storage. REU students will work closely with the PI and a graduate student or a postdoctoral associate in the Bardhan group.
 
Researcher Interests and Skills:This project is best suited for a student interested in experimental work. Students should have completed at least one college level physics course. Additionally one chemistry or biology or transport phenomena course would be valuable as well.

Nanosponge Materials for Drug Delivery

"Nanosponge Materials for Drug Delivery"
Eva Harth, Chemistry and Pharmacology

Degradable polyester materials continue to develop and advance towards targeted applications due to practical polymerization methods and the integration of functional groups (Figure 2). This development is apparent in the diversity of linear polyester materials but has not translated into 3-D polyester materials. Although 3-D polyester materials are still one of the most important controlled release systems, significant differences in preparation that would give easy access to materials with improved structural or physicochemical parameters, has not yet been accomplished. The development of robust methodologies that enable the preparation of a wide range of controlled but versatile polyester particles with access to tailored properties is therefore in high demand. REU students working in the Harth group would be involved in the preparation of functionalized polyester nanoparticles derived from á-valerolactone and å-caprolactone monomer families via intermolecular cross-linking processes that are differentiated by the amount of added cross-linking units of hydrophilic and hydrophobic nature via epoxide/amine reactions and allyl-thiol reactions and cross-linking density, and the preparation of particles that are differentiated by the molecular weight of the cross-linking unit to provide particles with a wide variety of cavities for encapsulation of low and macromolecular therapeutics, such as taxol or peptides/proteins. The students will investigate reactions that cross link functionalized water-soluble polyester chains to entrap oligonucleotides in aqueous solutions and investigate encapsulation potential of the prepared nanoparticles for applications as biomaterials.
 
Researcher Interests and Skills:  This project would be best suited for a student with an interest in drug delivery and specifically cancer therapy. The student should have completed a laboratory course and interests in organic chemistry and biology are beneficial.  The student will work in an interdisciplinary setting with chemical biologist, chemists and polymer chemists with experiences in nanobiotechnology for therapy.  

Nanovaccines

"Nanovaccines"
James Crowe, Microbiology & Immunology

Increasingly, there is a realization that the similarities in size and general structural features between nanoparticles and their biological counterparts could translate into significant applications of nanoparticles to a wide variety of fields in biology and medicine.  As a vaccine delivery vehicle, gold nanoclusters are very attractive candidates.  One promising application consists of gold nanoclusters of approximately 2 - 6 nm in diameter stabilized by an estimated 140-150 monodentate ligands on its surface, some of which are exchanged with antigens, molecules that elicit an immune response in the body; the gold nanoparticles can then yield a high level of antigen presentation to the immune system.  Colloidal gold can be absorbed into cells via macrophages (white blood cells that help to initiate specific defense mechanisms in the immune response to foreign invaders), and can thus be safely used in human immunotherapy, establishing the plausibility of using these materials as vaccine platforms.  Respiratory syncytial virus (RSV) is the leading viral cause of severe lower respiratory tract infections, accounting for an estimated 65 million infections and 1 million deaths annually worldwide.  Despite the significant health burden produced by RSV, there is currently no licensed RSV vaccine.  The Crowe group is investigating new approaches to both developing an RSV vaccine candidate and to vaccine development in general, using the gold-nanoparticle-based nano-vaccine delivery vehicles proposed above.  An REU student would assist with experiments to produce the functionalized nanoparticles, and determine the magnitude and quality of the antibody response to each vaccine candidate.  The student will work under the supervision of the faculty advisor and a postdoctoral fellow driving the research, with the goal of leading the student from an initial dependent status to more independent work.  The student will gain firsthand experience in laboratory research, be exposed to biological concepts in the area of vaccine immunobiology and concepts in fundamental materials science and engineering of composite materials.
 
Researcher Interests and Skills: Human antibodies, virus immunology, vaccines.

Oxidative Stress - Responsive Shape Memory Polymeric Scaffolds

"Oxidative Stress - Responsive Shape Memory Polymeric Scaffolds"
 Hak-Joon Sung, Biomedical Engineering

The PI proposes to program two “smart” functions (i.e., oxidative stress-responsiveness and shape memory function) into polymeric scaffolds by employing reactive oxygen species (ROS)-degradable peptide crosslinkers and shape memory polymers. These “smart” functions of biomaterials will be evaluated as a form of an injectable scaffolds. The proposed research will advance the state of the art in methods and techniques for applications of “smart” biomaterials to develop therapeutic inventions.
 
Researcher Interests and Skills:This project is best suited for a student interested in smart biomaterials. Students should have completed at least three semesters of a laboratory course.

Photosynthesis-Inspired Films for Solar Energy Conversion

"Photosynthesis-Inspired Films for Solar Energy Conversion"
Kane Jennings, Chemical and Biomolecular Engineering

Our society is experiencing the early stages of an energy crisis that will only intensify as long as alternatives to fossil fuels are not economically competitive. Jennings, in collaboration with David Cliffel (VINSE faculty in Chemistry), is developing new strategies for energy conversion that are inspired by photosynthesis, Nature’s solar energy conversion system. Specifically, they are developing biohybrid solar cells in which the active component is a dense film of Photosystem I (PSI), a nanoscale protein complex in plants that is one of the primary machines that drives photosynthesis. Recent discoveries by the Jennings/Cliffel team have led to dense PSI films adsorbed onto p-doped silicon (p-Si) surfaces that produce greatly enhanced photoelectrochemical current over that of p-Si alone.  Their most recently published photocurrents,1approaching the milliamp per cm2 range, are 6 orders of magnitude greater than those first reported by this team in 20072and have set a new standard worldwide.  The proposed work is focused toward the preparation of a solid-state cell in which a PSI film is sandwiched between two electrodes. While working in Jennings’ group, the REU participant will learn to extract and isolate PSI from spinach, selectively assemble it into dense films onto a prepatterned, chemically tailored electrode surface, characterize its composition and structure on the surface, and measure the amount of photocurrent that is produced from the PSI layer in a solid-state cell configuration. We expect that the REU participant will learn key aspects of photosynthesis, the fabrication of biomolecular films, the extraction of protein, strategies for solar energy conversion, and the characterization of surfaces.
 
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. 

Cited References
   1. LeBlanc, G.; Chen, G.; Gizzie, E. A.; Jennings, G. K.; Cliffel, D. E. Adv. Mater. 2012, in press.
    2. Ciobanu, M.; Kincaid, H.; Lo, V.; Jennings, G. K.; Cliffel, D. E. J. Electroanal. Chem. 2007, 599, 72.

Quantum Dynamics at the Nanoscale

"Quantum Dynamics at the Nanoscale"
 Kalman Varga, Physics and Astronomy

The main activity of the group led by Kalman Varga is computational modeling and simulation of electronic and transport properties of nanostructures. The group is interested in time dependent electron dynamics including field emission, laser excitation, and 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.

Radiation Detection using Nano and Microscale Fluorescing Particles

"Radiation Detection using Nano and Microscale Fluorescing Particles"
Bridget Rogers, Chemical and Biomolecular Engineering & Greg Walker, Mechanical Engineering 

We are investigating the possibility of using ceramic phosphors as indicators of radiation exposure.  We are studying how radiation exposure changes the spectra emitted by particles made of different fluorescing materials.  The project tasks include fabrication of the particles, irradiation of the particles, and physical, chemical, and optical characterization of the particles before and after irradiation. This project would support one or two undergraduate researchers who would work closely with graduate students and Prof. Rogers/Prof. Walker.  

Researcher Interests and Skills:  The project is best suited for students interested in experimental work.  Students must have completed three semesters of laboratory course work, preferably in a combination of chemistry and physics courses. 

Radiation Effects and Reliability in Electronics Devices

"Radiation Effects and Reliability in Electronics Devices"
Ron Schrimpf, Electrical and Computer Engineering

The Radiation Effects and Reliability Group focuses on understanding the performance of advanced electronic technologies in space environments, emphasizing the response to energetic radiation (e.g., cosmic rays). In space, and increasingly in terrestrial systems, the interaction of naturally occurring radiation with microelectronic systems is becoming a critical factor in their reliability. The size of the area affected by the interaction of a single radiation quantum with the materials of an integrated circuit is set by fundamental physics. Integrated circuit structures, on the other hand, have been shrinking for decades, and now, as they move comfortably into the nano-scale, they are becoming much smaller than the characteristic size of radiation events. The result is an interaction of extreme and increasing complexity. In order to understand this interaction and to design systems that minimize its negative effects, physics models of unprecedented complexity are needed. The Vanderbilt radiation effects program is working to change the fundamental paradigm of electronic design for extreme environments by the synthesis of first-principles nanoscale physics with higher-level models of microelectronic device and system response. The RER Group includes 10 professors, 13 graduate engineers, and approximately 30 graduate students. Undergraduate students also participate in space experiments through the Group's small satellite program.
 
Research Interests and Skills: The ideal students will be interested in semiconductor device physics and numerical simulation methods. They also will acquire experience with high performance computing/parallel computation.

Synthetic Biomaterials for Regenerative Medicine

"Synthetic Biomaterials for Regenerative Medicine"
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.

Towards high mobility graphene for electronics application

"Towards high mobility graphene for electronics application"
 Kirill Bolotin, Physics 

Graphene, a newly discovered two-dimensional form of carbon is actively considered for applications in electronics. One of the most important aspect of graphene is its mobility, which characterizes the speed of propagation of electrons in graphene. The goal of the project will be to explore placing of graphene on various substrate and engineering its coatings with the final goal of obtaining high-electron mobility electronic devices made of graphene. The project will include fabrication of devices with nanometer-scale dimensions using the techniques similar to those in semiconducting industry, low-noise electrical and mechanical measurements and computer modeling.

Researcher Interests and Skills: This project is best suited for a student interested in becoming a "quantum mechanic". This description includes interests in nanoelectronic materials and processing, cutting-edge device fabrication and characterization. Student should enjoy working in a laboratory setting and like making things work.

Ultra-Fast Laser Studies of Surfaces and Interfaces

"Ultra-fast Laser Studies of Surfaces and Interfaces
Norman Tolk, Physics and Astronomy

The Tolk group utilizes ultra-fast tunable lasers to study the dynamics of electronic and vibrational excitations in single crystal semiconductor structures.. The group is actively engaged in the following research thrusts: (A) Optical and electronic properties of multilayered semiconducting and spin systems using coherent acoustic phonon (CAP) spectroscopy. Intense optical excitation from ultrafast pulsed lasers generates a traveling acoustic phonon wave, which reflects optical pulses. These reflections, when combined with the surface reflection of samples, produce interferometric oscillations in the reflectivity signal, providing information about the electronic, magnetic, and optical properties of samples as a function of depth. Current systems under study include ion-damaged GaAs, Si, and diamond, as well as magnetic quantum well systems in GaAs and other substrates. (B) Second-harmonic generation studies of semiconducting and piezoelectric systems. Intense optical pulses interact nonlinearly with media to induce frequency doubling and multiphoton absorption. Such effects are observable as time-dependent changes in reflectivity and transmission signals. The ultimate goal of this research direction is not only to characterize materials in new ways but also to employ these techniques as a novel approach to quantum control to choreograph and modify materials far from equilibrium.
 
Researcher Interests and Skills: This project is best suited for a student interested in ultrafast (femtosecond, attosecond time scales)laser interactions with materials. Students should have some background in optics and modern physics.

Using Computational Tools to Design Nanoscale Building Blocks

"Using Computational Tools to Design Nanoscale Building Blocks"
Peter Cummings, Chemical and Biomolecular Engineering

Metallic nanowires have shown potential to meet the demand of the miniaturization of electronics due to their promising structural and electrical properties. These properties can be classified in specific metals by straining nanowires.  In this study, gold, platinum, silver, copper and aluminum nanowires were elongated with a constant applied tensile strain rate at 10 K and 298 K.  Elongation was simulated using molecular dynamics with the second moment approximation of the tight binding potential.  Different deformation modes, characterized by necking and slip planes, were exhibited in each metal.  The different deformation modes were identified by an analysis of the stress-strain relationship, changes in the minimum cross-sectional area and visual inspection.  For smaller nanowires, the conductance was shown to be strongly dependent on structural changes and impurities.  Decreases in conductance up to 28% of the initial crystalline structure were caused by slip planes and twin boundaries; drastic changes of the structure were correlated with sudden changes of the conductance.
  
Researcher Interests and Skills: The REU student will work with graduate students and post-doctoral researchers in the project to participate in developing and testing the computational tools being developed in this project.  Some expertise in programming is needed to participate in this project.  The student will also participate in a one-week CyberCamp being organized at Vanderbilt held annually at Vanderbilt in late May/early June.

Using Photosystem I for Solar Energy Conversion

"Using Photosystem I for Solar Conversion"
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.