Bourns Hall

Colloquium

Xuan Zhang Ph.D. candidate, Mechanical Engineering, UCR Guided Neurite Growth on Patterned Carbon Nanotubes Abstract Nanoscale substrates are suitable for functioning as cell scaffolds. Not only do they provide support to the developing cells but also allow for in-situ monitoring. Neurons are electrically excitable mammalian cells that on network formation serve as conduits for information transfer. A vast amount of information is transferred through the cells in the spinal cord via synaptic and gap junctions in the electro-ionic fashion mediated by neutrotransmitters. Carbon nanotubes (CNT) are strong, flexible and conduct electrical current. They are biocompatible and non-biodegradable. They can be functionalized with different biomolecules like neuron growth factors and adhesion agents, properties that come useful in formation of neuron hybrids. These properties of the nanotubes make them potentially successful candidates to form prosthetic substrates to guide neurite outgrowth. A combination of microlithography and chemical vapor deposition is used to engineer patterned vertical multiwalled carbon nanotube substrates. These substrates function as scaffolds and are used to demonstrate the formation of directed neuronal networks. Multiple substrate geometries and nanotube heights were fabricated to determine the most suitable combination for understand the cell morphological changes. Changes in the interaction between the cell membrane and the nanotube substrate are visually characterized. Cell viability was determined using calcium stains. Biosketch Xuan Zhang is currently a PhD student in the ME department of UCR. His research areas include: studying the interface between organic and inorganic materials, bio-sensors and nano-materials. Friday, January 14, 2005 Bourns Hall A265 3:10 p.m. - 4:00 p.m. (Refreshments will be served at 3:00 p.m.)