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Imaging three-dimensional rotational diffusion of plasmon resonant gold nanorods using polarization-sensitive optical coherence tomography.

ABSTRACT: We demonstrate depth-resolved viscosity measurements within a single object using polarized optical scattering from ensembles of freely tumbling plasmon resonant gold nanorods (GNRs) monitored with polarization-sensitive optical coherence tomography. The rotational diffusion coefficient of the GNRs is shown to correlate with viscosity in molecular fluids according to the Stokes-Einstein relation. The plasmon resonant and highly anisotropic properties of GNRs are favorable for microrheological studies of nanoscale properties.

SUBMITTER: Chhetri RK

PROVIDER: S-EPMC3116207 | biostudies-other | 2011 Apr

REPOSITORIES: biostudies-other

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Imaging three-dimensional rotational diffusion of plasmon resonant gold nanorods using polarization-sensitive optical coherence tomography.

Chhetri Raghav K RK Kozek Krystian A KA Johnston-Peck Aaron C AC Tracy Joseph B JB Oldenburg Amy L AL

Physical review. E, Statistical, nonlinear, and soft matter physics 20110412 4 Pt 1

We demonstrate depth-resolved viscosity measurements within a single object using polarized optical scattering from ensembles of freely tumbling plasmon resonant gold nanorods (GNRs) monitored with polarization-sensitive optical coherence tomography. The rotational diffusion coefficient of the GNRs is shown to correlate with viscosity in molecular fluids according to the Stokes-Einstein relation. The plasmon resonant and highly anisotropic properties of GNRs are favorable for microrheological st ...[more]

PMID: 21599108

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