Institute for Critical Technology and Applied Science Seminar Series

The Influence of Particokinetics on Toxicology: Do Nanoparticles Change Over Time?with Christie Sayes,Program Manager, Nanotoxicology & Nanopharmacology at RTI International

Thursday, November 15, 2012, 2:30 - 4:00 pmICTAS on Stanger, Room 310

Nanotechnology is most commonly driven by the increasing importance of very small particles in a variety of applications. These applications mainly reside in technologies stemming from the electronic or optical sensing approaches. With the advent of surface functionalization on very small particulates, however, gave way to the birth of nanomedicine and nanotoxicology. Our research continues to investigate the interface between the hydrophobic nature of inorganic nanostructures and the hydrophilic nature of biology. As part of the R&D in biological applications, we also study the unintended implications of engineered nanomaterials. Particles are carefully selected in groups of similar physicochemical properties, characterized as they transform over time, and exposed to mammalian and bacterial systems. Properties such as particle size, surface charge, and chemical composition are related to specific pathway-specific biological responses such as apoptotic, oxidative stress, or other immune or inflammatory events. Results of these studies provide insights on how engineered nanomaterial features influence cellular responses and thereby outline possible approaches for developing and applying predictive models for biological responses caused by exposure to nanomaterials.

Dr. Christie M. Sayes is the Program Manager for Nanotoxicology & Nanopharmacology in the Center for Aerosols and Nanomaterials Engineering at RTI International. She was formerly a professor of toxicology at Texas A&M University. Dr. Sayes maintains her adjunct faculty appointment at Texas A&M in the Department of Biomedical Engineering and the Interdisciplinary Program in Toxicology. She has more than a decade of experience in the fields of nanotechnology and nanotoxicology. She has authored numerous publications, including original research, invited reviews and book chapters. She is a member of the Society of Toxicology, the American Chemical Society, and the Society of Environmental Toxicology and Chemistry. She serves on the Scientific Advisory Board for the EPA’s FIFRA Program and on the Editorial Board of the journals Nanotoxicology and Toxicology Letters. Recently, she was elected onto the Executive Committee of the North Carolina Chapter Society of Toxicology. Dr. Sayes has proven abilities in providing technical guidance and leadership to students, technicians, and colleagues; a high aptitude for development of complex particle toxicological and biocompatibility basic and applied research

projects in cell culture based and animal based models; substantial training in nanomaterial & nanotoxicology research techniques & instruments; significant experience working independently & collaborating across disciplines and organizations; excellent communication and interpersonal skills with colleagues in science and engineering, senior management, and new and existing clients and other funding sources.The goal of the research performed in her laboratory is to investigate the fate, transformation, and biological effects of nanoparticles and nanomaterial systems. Her group addresses several fundamental issues relevant to the development safe and effective nanomaterials in biological and environmental applications. These issues include, but are not limited to, the following parameters: the importance of material characterization, dose-response & time-course, correlation of in vitro findings to in vivo results, mechanistic & synergistic analyses, developing mathematical and computational models for predicting nanoparticle toxicities, and defining appropriate endpoints in hazard identification and exposure conditions for risk evaluation.