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arXiv · 1108.2337

Plasmonic Nanoparticle-based Protein Detection by Optical Shift of a Resonant Microcavity

Miguel A. Santiago-Cordoba·Svetlana V. Boriskina·Frank Vollmer·Melik C. Demirel
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Abstract

We demonstrated a biosensing approach which, for the first time, combines the high-sensitivity of whispering gallery modes (WGM) with a metallic nanoparticle based assay. We provided a computational model based on generalized Mie theory to explain the higher sensitivity of protein detection through Plasmonic enhancement. We quantitatively analyzed the binding of a model protein (i.e., BSA) to gold nanoparticles from high-Q WGM resonance frequency shifts, and fit the results to an adsorption isotherm, which agrees with the theoretical predictions of a two-component adsorption model.

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Miguel A. Santiago-Cordoba, Svetlana V. Boriskina, Frank Vollmer, Melik C. Demirel. 2011-08-11. Plasmonic Nanoparticle-based Protein Detection by Optical Shift of a Resonant Microcavity. https://doi.org/10.1063/1.3599706

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