Translational and rotational diffusion of gold nanorods near a wall.

We measured the rotational and translational diffusivity of dilute gold nanorods in aqueous suspension close to a hard planar wall. Therefore, resonance enhanced dynamic light scattering, an evanescent technique, was applied, making use of the strong scattering intensity near the longitudinal surface plasmon resonance frequency of the particle. We observed a slowing down beyond the known hydrodynamic models.