Prof. Amanda Haes, University of Iowa

Designing nanomaterials for biosensor platforms

Noble metal nanoparticles exhibit novel size-dependent properties which are being exploited in many applications. In this talk, the architecture, stability, and surface chemistry of solution-phase gold and silver nanoparticles will be correlated to nanoparticle function in the capillary electrophoresis separation of Parkinson’s disease biomarkers and surface enhanced Raman scattering (SERS) detection of small molecules. Nanoparticle concentration, core composition, and surface chemistry will be shown to play an important role in the capillary electrophoresis separation of both nanoparticles themselves and disease biomarkers. Interactions between nanoparticles and (1) other nanoparticles, (2) the capillary wall, and (3) target molecules will be shown to depend on the surface chemistry and charge on the nanoparticles as well as on nanoparticle concentration. Second, a novel method which entraps gold or gold-coated silver nanoparticles in thin silica membranes will be demonstrated. The silica membrane prevents electromagnetic coupling between the nanoparticle cores without blocking the active metal surface for enhanced SERS and refractive index sensing. Applications related to the direct and quantitative detection of small molecules will be discussed. Improvements in understanding what is on the surface chemistry of a nanoparticle and how that surface chemistry influences the activity of the nanoparticles will have ultimate implications on the detection of target biological and environmental toxins.

For more information contact Prof. Andrew Lyon (404-894-4090).