Department of Chemistry Seminar Announcement

Date/Time/Venue

Title/Speaker

14 Feb (Mon)11am – 12nn

@ S8 Level 3 Executive Classroom

Physical-Chemical Properties Physical-Chemical Properties Controlling the Environmental Controlling the Environmental Fate of NanoparticlesFate of NanoparticlesProfessor Andrew M ShawProfessor Andrew M ShawUniversity of Exeter, UKHost : Assoc Prof Thorsten Wohland

About the Speaker

All are Welcome

AbstractThe physico-chemical properties of the nanoparticles ZnO and CeO2 are considered with respect to their stability and ultimate fate in the environment and subsequent toxicity. The negatively charged ZnO particles found in Nanosun and Z-cote commercial materials have good dispersion stabilities in pure water and poor stabilities in salty media. The empirical half-life of these dispersions and the mechanisms of stabilisation will be considered including NICCA adsorption isotherms and adsorption kinetics. Results from evanescent wave cavity ring-down spectroscopy and their quantitative analysis of the resulting charged interface structure will be presented. The concentration of nanoparticles in OECD soil samples is assayed using a new photo-radical generation assay and this is used to determine the effects of nanoparticle dissolution relative to stability. Adsorption of Zn2+ to OECD clay surfaces is also considered as a time-dependent source of toxic Zn. The metal and radical stress responses of E. coli are considered as a comparison organism-level assay of the physical and chemical properties in the nanoparticle toxicity.

Professor Andrew M Shaw received his MA in Natural Sciences from University of Cambridge and PhD in Physical Chemistry from University of Southampton in 1992.  He carried out his postdoctoral research in Stanford University in 1999.  He joined the faculty at the University of Exeter in 2001 and is currently an Associate Professor of Physical Chemistry.  He is also the Founder and Director of Research of EvanesCo Ltd.  His research uses the principles of physical chemistry to make measurements on systems in Chemical Biology. His researchgroup is currently developing a screening technology that will allow the concentrations of molecules in blood to be measured that may act as biomarkers of disease and extend the field of differential diagnosis. His research concentrates on the fundamental the quantitative description of measurements interpreted with a mathematical model. The research directions have led to the formation of a company to exploit the technology commercially with application in the petrochemical industry, production quality monitoring and Homeland Security.  Teaching interests in the School are Physical Chemistry for the Life Sciences, Astrochemistry and Astrobiology and Forensic Science. All modules explore the quantitative interpretation of physical processes. He has written a textbook Astrochemistry: From Astronomy to Astrobiology, published by Wiley in 2006.