Contact: Dr. Abebe Kebede
336-285 2113 or email

Space Science

Astronomy and Astrophysics
Material Science
Nuclear Physics

Dr. Ray Hoff

  Mark R. Wiesner, Ph.D., P.E

Mark R. Wiesner, Ph.D., P.E.
James L. Meriam Professor of Civil and Environmental Engineering
Pratt School of Engineering
Nicholas School of the Environment and Earth Sciences
Duke University
Box 90287 120 Hudson Hall Durham, NC 27708-0287
URL:  Mark R. Wiesner Research Group
February 9, 2009

Marteena Hall, Room 310  Time- 4:00 PM

Title: Physical-chemical factors controlling nanoparticle exposure, transformation and reactivity

The properties of nanomaterials are transformed significantly due to interactions with environmental and physiological matrices. This presentation explores the role of nanomaterial-macromolecule interactions as they affect aggregation, deposition and reactivity using fullerenes as an example. The chemistry of reactive oxygen species (ROS) generation is presented and the relationship between the morphology of nanoparticle aggregates and their reactivity is explored. Alternations to nanoparticle ROS production as the result of matrix effects, in particular those representing commonly used growth media, are discussed. Changes in the affinity of fullerenes for a references solid phase are presented as function of the nature of adsorbing macromolecules, and the significance of these results for nanoparticle transport are highlighted. Finally, the importance of accounting for nanoparticle transformations in bioavailability and toxicity studies is discussed.