ChBE Seminar Series: Matt Kipper
Tuesday, October 28, 2008
11:00 a.m.-12:15 p.m.
Room 2110, Chemical and Nuclear Engineering Bldg.
Professor Ganesh Sriram
Tailoring Polysaccharide Nanostructures for Biomedical Materials
Presented by Matt Kipper
Assistant Professor, Department of Chemical and Biological Engineering
Associate Director, School of Biomedical Engineering
Colorado State University
Polysaccharides are biologically derived macromolecules that have a wealth of biological function, which is still being explored through glycobiology, and represents an enormous potential for engineered biomaterials. In addition to providing structural and mechanical properties for tissues and organs, polysaccharides have binding domains for proteins such as enzymes, cytokines, and other extracellular matrix components, which potentiate their activity and organize their structure. Thus, polysaccharides are excellent candidate materials for introducing biochemical functionality into materials for applications such as tissue engineering. In their native biological contexts, polysaccharides are organized at multiple length scales, including the nanometer length scale. Recent experimental reports confirm that the responses of cells and tissues to engineered biomaterials are sensitive to the nanoscale structure and organization of materials. Thus, we are developing polysaccharide-based nanostructures in order to investigate their emergent biological properties of more complex nanoassemblies.
Of particular interest in the work discussed here is the polyelectrolyte nature of polysaccharides. Pendent carboxylic acid, amine, and sulfonate moieties impart strong and weak polyelectrolyte properties to polysaccharides. These electrostatic interactions can be used to tune the nanostructure and surface properties of polysaccharide-based materials. This talk will discuss three types of nanostructures: (1) nanoscale polyelectrolyte multilayer (PEM) surface coatings, (2) polyelectrolyte complex nanoparticles (PCN), and electrospun nanofibers. These three types of nanostructures (representing control over composition in rectangular, spherical, and cylindrical coordinates) can be combined to form more complex assemblies. We are interested in developing techniques to tune the electrostatic interactions that govern the assembly of these nanostructures and exploring how the nanoscale structure and composition of these materials affects the adsorption and stabilization of therapeutic proteins, and the responses of mesenchymal stem cells that can be used for skeletal tissue engineering.