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Nanoplasmonic Upconverting Nanoparticles as Orientation Sensors for Single Particle Microscopy.

ABSTRACT: We showed that the anisotropic disk shape of nanoplasmonic upconverting nanoparticles (NP-UCNPs) creates changes in fluorescence intensity during rotational motion. We determined the orientation by a three-fold change in fluorescence intensity. We further found that the luminescence intensity was strongly dependent on the particle orientation and on polarization of the excitation light. The luminescence intensity showed a three-fold difference between flat and on-edge orientations. The intensity also varied sinusoidally with the polarization of the incident light, with an I_max/I_min ratio of up to 2.02. Both the orientation dependence and I_max/I_min are dependent on the presence of a gold shell on the UCNP. Because the fluorescence depends on the NP's orientation, the rotational motion of biomolecules coupled to the NP can be detected. Finally, we tracked the real-time rotational motion of a single NP-UCNP in solution between slide and coverslip with diffusivity up to 10^-2??m²s^-1.

SUBMITTER: Green KK

PROVIDER: S-EPMC5429696 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Nanoplasmonic Upconverting Nanoparticles as Orientation Sensors for Single Particle Microscopy.

Green Kory K KK Wirth Janina J Lim Shuang F SF

Scientific reports 20170410 1

We showed that the anisotropic disk shape of nanoplasmonic upconverting nanoparticles (NP-UCNPs) creates changes in fluorescence intensity during rotational motion. We determined the orientation by a three-fold change in fluorescence intensity. We further found that the luminescence intensity was strongly dependent on the particle orientation and on polarization of the excitation light. The luminescence intensity showed a three-fold difference between flat and on-edge orientations. The intensity ...[more]

PMID: 28396602

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