Archives—September 2011

Design and Application of Bioadhesives Inspired by Marine Mussels

Friday, September 30 at 3:00—U113 M&M Building

Bruce Lee, Asst. Professor, Biomedical Engineering

Bioadhesives have a wide range of important applications in the biomedical field. Tissue adhesives simplify complex surgical procedures to achieve effective wound closure and surgical repair. Despite these important functions, currently available adhesives seldom meet the basic requirements for in vivo applications because of possible disease transmission, poor adhesive quality, or toxicity concerns. Thus, there is an ongoing need for the development of tissue adhesives with improved characteristics. Nature provides many outstanding examples of adhesive strategies from which chemists and materials scientists can draw inspiration in their pursuit of new biomaterials. Of particular interest is the mussel adhesive protein (MAP) secreted by marine mussels. MAP is initially secreted as a proteinaceous fluid, and then subsequently harden in situ to form an adhesive plaque, which allow mussels to bind tenaciously to various types of sur- faces underwater. One of the unique structural features of MAP is the presence of L-3,4- dihydroxyphenylalanine (DOPA), an amino acid post-translationally modified from tyrosine, which is believed to fulfill the dual role as the adhesive moiety and the crosslinking precursor. My research had focused on the incorporation of DOPA and its derivatives in creating synthetic mimics of MAPs for various medical applications. In this seminar, I will discuss the design and application of these biomimetic adhesive materials.

Imaging Sub-pixel Motion using Optical Coherence Tomography

Friday, September 16 at 3:00—U113 M&M Building

Niloy Choudhury, PhD, Department of Biomedical

It is important to measure sub-pixel motion in biological specimen as it allows us to investigate wide range of biological phenomenon ranging from micro-mechanical motion in tissue to estimating metabolic activity. Optical Coherence Tomography is one such technique that can provide images of sub-pixel motion with cellular level resolution (~10 μm). A Time Domain Optical Coherence Tomography (TD-OCT) based system has been developed to investigate “hearing mechanism” by measuring sub nanometer motion of the organ of Corti in a guinea pig. A 3-D optical micro-angiography system based on the principles of Fourier Domain Optical Coherence Tomography (FD-OCT) has also been developed. Combining the FD-OCT system with a novel imaging process allows us to achieve full depth of scan for structural and blood flow measurements. Using this novel device Micro-circulation in a gerbil cochlea is investigated as it is believed that a change in blood flow influences a number of cochlear diseases that can lead to