Research Project: Two-way Shape Actuators
Actively moving polymers are recognized for their potential to serve in a plethora of biomedical devices including vascular stents, clot-removal devices, catheters, programmable sutures, implants, etc. Such applications demand that materials perform significant mechanical work against external loads; therefore they must exhibit high shape energy densities. This summer project will investigate the chemistry and mechanics of covalent poly(caprolactone) (PCL) networks that contain both static and photosensitive crosslinks. Networks will be manipulated using applied forces and UV-light to create two superimposed networks that are interlocked with opposing stress. This, combined with the stress-induced crystallization behavior of poly(caprolactone), will form the basis of an attempt to demonstrate a single-component, thermal responsive, two-way shape actuator.
Research Project: Hydrogel Culture Environments for Regenerative Medicine Applications
We can interrogate and take advantage of the critical interactions between cells and extracellular matrix (ECM) to create bioactive materials capable of controlling cell function and tissue evolution. To determine the requirements of the microenvironment, we utilize hydrogels easily modified with respect to mechanical integrity, adhesive peptides, ECM molecules, degradability, and incorporation of drugs, to direct cellular differentiation through a variety of mechanisms.In particular, we are interested in utilizing hydrogel microenvironments to direct encapsulated mesenchymal stem cell (adult stem cell) function for applications in musculoskeletal tissue engineering. A thorough understanding of how material properties effect cell differentiation and tissue evolution is essential to tailor ‘instructive materials’ to direct cell function.Targeted polymer therapeutics to overcome drug delivery barriersConventional small molecule drugs and large macromolecular drugs have significant and distinctly different delivery barriers. For example, small molecule drugs, such as the chemotherapeutic doxorubicin, is highly hydrophobic, thus administration requires toxic cosolvents to aid blood solubility. Macromolecular drugs, on the other hand, suffer from enzymatic degradation and inactivation, difficulty in targeting to the appropriate cells and transversing the cell membrane, and often become degraded intracellularly once endocytosed. We are investigating polymer-drug complexes or polymer-drug conjugates to overcome these barriers and modulate drug delivery.
Research Project: Quantitative Determination of the Abrasion Resistance of Cross-linked Sol-Gel Anti-Reflective Coatings for High-Peak-Power Lasers
Full research project description available here.
Research Project: Anisotropic surface functionalization of microneedles
Template synthesis is a very well-known method for fabricating an array of high aspect-ratio needles that are protruding from a flat substrate. The diameter of these needles can be as small as tens of nm, and the length can be in the order of microns. The needles can be made of metals, polymers, semiconductors and biomolecules. Such versatility and the simplicity of this method have led to its use in various fields including energy and biology. This summer research project is focused on developing a microfluidic-based setup that allows such microneedles to be coated with different molecules at the surface, and confer additional functionality to the microneedles.
Research Project: Additive manufacturing of high resolution electronic devices using contact transfer printing with elastomeric materials
The project will involve the development of novel polymers and printing techniques that can be used to manufacture patterned thin film-based devices with resolution below 10 micrometers.
Research Project: Genomics Study of Microbial Production of Bio-ethanol and Bio-hydrogen from Cellulosic Biomass as Renewable Energy Sources
The overall goal of this project is to turn waste biomass, such as grass clippings, cornstalks, and wood chips, into usable hydrogen or ethanol. The short-term objective is to understand how the bacterium controls the production of these two energy sources. Energy experts expect ethanol from biomass to replace at least 30 percent of the national gasoline consumption for transportation by 2030, and hydrogen is a promising future energy source that can be used in fuel cells with high efficiency. Deriving these energy sources from cellulosic biomass makes them renewable, eliminates competition with food supplies, and reduces carbon dioxide emission. The bacterium, called C. thermocellum, has the very rare ability to break down tough plant cellulose and convert it to hydrogen and ethanol. The DNA sequence of the genome of this bacterium, which contains more than 3,000 genes, has been determined. We plan to investigate the interactions among these thousands of genes and to formulate new strategies to efficiently produce hydrogen and ethanol. Molecular cloning, DNA microarrays and proteomic approaches will be employed to facilitate the study. Prior knowledge of biology and molecular biology will be useful for the project.