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arXiv · 0704.3816

Single metallic nanoparticle imaging for protein detection in cells

Laurent Cognet·Catherine Tardin·David Boyer·Daniel Choquet·Philippe Tamarat·Brahim Lounis
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Abstract

We performed a visualization of membrane proteins labeled with 10-nm gold nanoparticles in cells, using an all-optical method based on photothermal interference contrast. The high sensitivity of the method and the stability of the signals allows 3D imaging of individual nanoparticles without the drawbacks of photobleaching and blinking inherent to fluorescent markers. A simple analytical model is derived to account for the measurements of the signal amplitude and the spatial resolution. The photothermal interference contrast method provides an efficient, reproducible, and promising way to visualize low amounts of proteins in cells by optical means.

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Laurent Cognet, Catherine Tardin, David Boyer, Daniel Choquet, Philippe Tamarat, Brahim Lounis. 2007-04-28. Single metallic nanoparticle imaging for protein detection in cells. https://doi.org/10.1073/pnas.1534635100

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