MSE Seminar Series: Ashley A. White
Friday, February 3, 2012
1:00 p.m.-2:00 p.m.
Room 2110 Chemical and Nuclear Engineering Bldg.
301 405 5240
Hydroxyapatite/Multi-Walled Carbon Nanotube Composites for Bone Graft Applications
Ashley A. White
AAAS Science and Technology Policy Fellow
Division of Materials Research
National Science Foundation
As a biologically active ceramic, hydroxyapatite (HA) is used in surgery to replace bone. While HA promotes bone growth along its surface, its mechanical properties are not sufficient for major load-bearing medical devices. Carbon nanotubes (CNTs), as one of the strongest and stiffest materials available, have the potential to strengthen and toughen HA, thus expanding the range of clinical uses for the material. Furthermore, studies have suggested that the nanotubes themselves possess some bioactive properties.
Forming composites from this particular combination of materials presents unique challenges, particularly related to sintering, which is necessary to form a dense, strong monolith. The high temperatures necessary for sintering can oxidize CNTs, while the presence of water vapor or high pressure is necessary to retain HAs phase purity and hydroxylation. This talk will discuss production and characterization of unsintered composite materials, investigations into appropriate sintering atmospheres and techniques, evaluation of mechanical properties, and in vitro cell culture.
In addition, Dr. White will briefly discuss her recent experiences in science policy, including serving as an MRS-OSA congressional fellow in the U.S. Senate and her current position as a AAAS fellow in the Division of Materials Research at the National Science Foundation.
About the Speaker
Dr. White earned her PhD in Materials Science from the University of Cambridge as a British Marshall Scholar and NSF Graduate Research Fellow, where her thesis work focused on developing nano-structured bone graft materials. Following her PhD, she remained at Cambridge to continue this research and investigate the interaction of carbon nanotubes and infrared radiation for biological applications. She received her BS in Materials Science and Engineering from Virginia Tech, along with a BA in Music Performance. Her research at Virginia Tech and Lawrence Berkeley National Laboratory involved silica and composite aerogels for heat insulation applications. Additionally, Dr. White has worked on a number of other research projects at MIT, Cornell University, and the Thomas Jefferson National Accelerator Facility.
Currently, Dr. White is working in the Division of Materials Research at the National Science Foundation as an AAAS Science and Technology Policy Fellow. Last year, she worked in the office of Senator Al Franken as the MRS-OSA/AAAS Congressional Fellow, where she served as a policy advisor, with a particular focus on science, technology, engineering, and math education. In addition to her current position at NSF, she advises MSE students at Virginia Tech and is teaching a course there on the connections between science and music.