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Two-photon 3D FIONA of individual quantum dots in an aqueous environment.

ABSTRACT: We report the first two-photon (2P) microscopy of individual quantum dots (QDs) in an aqueous environment with both widefield and point-scan excitations at nanometer accuracy. Thiol-containing reductants suppress QD blinking and enable measurement of the 36 nm step size of individual Myosin V motors in vitro. We localize QDs with an accuracy of 2-3 nm in all three dimensions by using a 9 × 9 matrix excitation hologram and an array detector, which also increases the 3D scan imaging rate by 80-fold. With this 3D microscopy we validate the LamB receptor distribution on E. coli and the endocytosis of EGF-receptors in breast cancer cells.

SUBMITTER: Zhang R

PROVIDER: S-EPMC3192306 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature

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Two-photon 3D FIONA of individual quantum dots in an aqueous environment.

Zhang Ruobing R Rothenberg Eli E Fruhwirth Gilbert G Simonson Paul D PD Ye Fangfu F Golding Ido I Ng Tony T Lopes Ward W Selvin Paul R PR

Nano letters 20110913 10

We report the first two-photon (2P) microscopy of individual quantum dots (QDs) in an aqueous environment with both widefield and point-scan excitations at nanometer accuracy. Thiol-containing reductants suppress QD blinking and enable measurement of the 36 nm step size of individual Myosin V motors in vitro. We localize QDs with an accuracy of 2-3 nm in all three dimensions by using a 9 × 9 matrix excitation hologram and an array detector, which also increases the 3D scan imaging rate by 80-fol ...[more]

PMID: 21882883

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