Article

Evaluation of influence of anisotropic diffusion near a wall in near-field fluorescence correlation spectroscopy of nanoparticles

Optical Review (Impact Factor: 0.7). 01/2011; 18(2):237-240. DOI: 10.1007/s10043-011-0048-5

ABSTRACT Fluorescence correlation spectroscopy (FCS) of colloidal nanoparticles using a near-field fiber probe was numerically simulated.
The near-wall dynamics was simulated by accounting for the anisotropic mobility of nanoparticles owing to hydrodynamic interaction
with a wall (Stokes viscous force). By comparing the simulation results with theoretical model calculations, we found that
the influence of anisotropic diffusion is insignificant in near-field FCS autocorrelation analysis.

Keywordsnear-field optical microscopy–fluorescence correlation spectroscopy–hydrodynamics–diffusion coefficient

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