Biomaterials Research in Materials Science and Engineering
Biomaterials Research and Initiatives
MSE faculty, graduate students, and even some undergraduates are engaged in a variety of high-profile biomaterials-based projects. Below are only a few examples:
Professor Mohamad Al-Sheikhly and his research group are immobilizing DNA probes on a variety of semiconductor surfaces, which could benefit the development of molecular electronics, future computer architectures, and massive computer memory and storage. A fundamental understanding of the chemical interactions and properties of the dry/wet interface has become a key scientific issue in bio-inorganic hybrid systems applications. The group probes the attachment of DNA to inorganic semiconductor surfaces, hoping to develop nanoelectronics and related technologies based upon this hybrid system.
Professor Al-Sheikhly has also investigated the use of nanogels in drug delivery applications.
Nano-Roughness on Titanium Biomedical Implants
Professor Sreeremamurthy Ankem has developed a new implant fabrication technique that promotes a stronger implant/bone interface, resulting in an increase in the functional lifespan of the implant and a reduction in costs and patient stress. Ankem's new fabrication method involves creating micropores in the rough surface of the implant, producing a much greater surface area in the same space for bone cells to attach to. This adds little cost to the manufacturing process and is extremely economical when measured against the cost of additional surgeries.
X-Ray and Neutron Scattering for Analysis of Silk-Based Hydrogels
Robert M. Briber
Professor and Chair Robert M. Briber is using small angle x-ray and neutron scattering techniques to probe the structures of biological molecules, including the structural change of tRNA characterized using small angle x-ray scattering. The conformational change from unfolded state to compact state occurs as salt concentration increases, which matches quite well with theoretical prediction. The Briber Group also studies silk elastin-like peptide polymers which form hydrogels as their temperature increases. The Debye-Bueche correlation length obtained from small-angle neutron scattering has provided structural insight about the cross-linking densities in the hydrogels, suggesting the importance of the length of elastin blocks in governing the spacing of the cross-linked hydrogel networks, and that of silk in governing the stiffness of their 3-dimensional structures.
Novel Materials for Dental Applications
Isabel Lloyd, Associate Professor
Professor Isabel Lloyd is developing high modulus composite biomaterials for dental applications. They are based on a new class of adhesive composites filled with nano-alumina and micro-diamond fillers to effectively prevent any mechanical failure. She is also working on glass-based laminar composites for restoration to meet mechanical and aesthetic requirements.
Contrast Agents for Improved MRI
Oded Rabin, Assistant Professor
X-ray CT imaging of a live mouse before (above) and after (below) intravenous administration of the nanoparticle contrast agent. (Published in Nature Materials.)
Biomedical-imaging contrast-agents are formulations that are administered in conjunction with an imaging procedure (e.g. MRI) in order to improve the quality of the images obtained and in order to assign a physiologically-relevant weight to the contrast observed in the image (e.g. dark areas in the image corresponding to scar tissue from spinal cord injury, or fluorescence localized in cells transcribing the RNA sequence for a certain peptidase). Ideally, contrast-agents are easy to administer, are targeted to a specific target molecule, are inactive without the presence of the target molecule, are retained for the duration of the imaging procedure, and are completely removed from the body shortly thereafter. Professor Oded Rabin has developed the only known biodegradable nanoparticle formulation that can serve as an effective contrast agent for x-ray CT imaging of blood vessels, lymph nodes and the reticuloendothelial system. The bismuth sulfide particles used in the agent are 40nm wide, 5nm thick nanoplatelets coated with polyvinylpyrrolidone (PVP). The contrast agent has a long circulation time, and is effective until it accumulates in the spleen. Excellent-quality images of the vasculature and lymph nodes were obtained. The nanoparticles, however, could not be targeted, and the degradation time was prohibitively long. Current efforts are in developing a second generation of nanoparticle contrast-agents addressing the two short-comings of the first generation.
The Rubloff Group has developed a means to incorporate silver nanoparticles into chitosan in lab-on-a-chip devices. When using raman spectroscopy, these nanoparticles enhance the signal that is produced from nearby molecules, making it possible to detect small quantities of reaction products.
The Rubloff Group is developing an integrated microfluidic system to provide electric signals and optical access for biochemical assemblies. Microfluidic control systems provide systematic operation processes. Labview-based control systems coordinate liquid transport and electrodeposition. Compared to traditional physical entrapment and surface immobilization approaches in microfluidic environments, the group's signal-guided electrochemical assembly is unique in that the enzymes are assembled under mild aqueous conditions with spatial and temporal programmability and orientational control. The group believes that this assembly strategy can be applied to rebuild metabolic pathways in microfluidic environments for antimicrobial drug discovery
Shape Memory Alloys for Stents
Professor Ichiro Takeuchi
Stents are biomedical devices used to reopen and keep open blocked coronary arteries, helping to prevent heart attacks and strokes. They are considered effective alternatives to open heart surgery and balloon angioplasty. Professor Ichiro Takeuchi is using a combinatorial materials science approach to discover a shape memory alloy that can be used to develop a new, novel stent material. At room temperature, this stent would be compact, making it easier to be inserted into blood vessels. Once implanted, the patient's body temperature would cause it to automatically exapand and open the clogged artery.
Biotechnology Facilities and Laboratories
Our students, faculty and staff have access to and manage world-class facilities such as the Maryland NanoCenter, which includes the FabLab, a 10,000 ft2 clean room that supports research and development programs in micro-electromechanical systems, semiconductors, materials and devices for electronics, bioscience and bioengineering, and sensor/actuator systems; and the NISPLab, a microscopy facility focused on the characterization of materials and structures in the areas of biomaterials, multifunctional and smart materials, nanostructured materials, nanodevices and geological materials. The Keck Laboratory for Combinatorial Nanosynthesis and Multiscale Characterization conducts research using combinatorial materials science, scanning nanoprobes, and highly controlled materials synthesis.
For a more comprehensive listing of the Department's facilities and equipment, please visit our laboratories page.