AVS 51st International Symposium
    Biomaterial Interfaces Tuesday Sessions
       Session BI+NS-TuM

Paper BI+NS-TuM7
Label-Free Biosensor Based on the Surface Plasmon Resonance of Gold Nanoparticles

Tuesday, November 16, 2004, 10:20 am, Room 210D

Session: The Nano-Bio Interface
Presenter: S.M. Marinakos, Duke University
Authors: S.M. Marinakos, Duke University
N. Nath, Duke University
A. Chilkoti, Duke University
Correspondent: Click to Email
The optical properties of gold nanoparticles immobilized on a surface were used in a label-free biosensing scheme. The sensing modality is based on the change in the local refractive index associated with receptor-ligand binding at the particle surface which shifts the surface plasmon resonance (SPR) peak in the absorbance spectra of the nanoparticles. In previous work, we have shown that solid, spherical gold nanoparticles with a size in the range of 13-50 nm could be self-assembled on amine-functionalized glass. These chemisorbed nanoparticles were then functionalized with a biotin derivative. We showed that this scheme enabled single wavelength monitoring of streptavidin binding at the surface by single wavelength measurements of the change in intensity that was caused by binding of streptavidin at the nanoparticle-solution interface. In this study, we extend these measurements to anisotropic gold nanorods, in an effort to further improve the analytical sensitivity and detection limits of this label-free transmission optical sensor. Results will be presented that compare streptavidin-biotin binding with sensors fabricated from gold nanorods with previous results on spherical gold nanoparticles.