Seminar Abstract:
Plasmonic nanostructures have long been known to manipulate light to yield unique optical properties. In this essence, my talk will discuss how optical properties of plasmonic nanostructures can be harnessed to understand fundamental physical processes directly relevant for biomedical and energy applications. First I will show how metal nanoshells, plasmonic nanostructures consisting of a silica core wrapped in a gold shell, when coupled to fluorophores in their vicinity give rise to remarkable distant-dependent enhancements in their emissive properties. I will particularly describe the fluorescence enhancement of clinically relevant and FDA-approved near-infrared fluorophore, Indocyanine green. Then I will describe the use of these enhanced fluorescent nanoshells combined with iron oxide nanoparticles and targeting moieties for multi-modal MRI and fluorescence imaging, and targeted photothermal therapy of cancer cells both in vitro and in vivo. I will show in situ tracking of these multifunctional nanoshells in vivo providing detailed information regarding the distribution and fate of complex nanoparticles designed for specific diagnostic and therapeutic functions.
In the next part of my talk I will discuss the use of plasmonic nanostructures as probes for the design of next-generation hydrogen storage systems. Currently, experimental understanding of how nanoparticle size controls the kinetics and thermodynamics of metal-hydride formation and decomposition is limited due to challenges both in directly probing these events at the nanoscale, and preparing uniform samples over a series of sizes. By developing a sensitive optical technique to monitor the luminescence of metal nanocrystals in-situ, I will present experimental results detailing the thermodynamics and kinetics of hydride phase transformations within a size-series of monodisperse palladium nanocrystals. This in situ optical approach enables a detailed understanding of how nanocrystal surfaces impact the energy barriers to hydride nucleation which directly impacts the design of practical high-performance hydrogen storage materials.