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arXiv · 1506.06339

Nanodiamond Landmarks for Subcellular Multimodal Optical and Electron Imaging

Abstract

There is a growing need for biolabels that can be used in both optical and electron microscopies, are non-cytotoxic, and do not photobleach. Such biolabels could enable targeted nanoscale imaging of sub-cellular structures, and help to establish correlations between conjugation-delivered biomolecules and function. Here we demonstrate a subcellular multi-modal imaging methodology that enables localization of inert particulate probes, consisting of nanodiamonds having fluorescent nitrogen-vacancy centers. These are functionalized to target specific structures, and are observable by both optical and electron microscopies. Nanodiamonds targeted to the nuclear pore complex are rapidly localized in electron-microscopy diffraction mode to enable "zooming-in" to regions of interest for detailed structural investigations. Optical microscopies reveal nanodiamonds for in-vitro tracking or uptake-confirmation. The approach is general, works down to the single nanodiamond level, and can leverage the unique capabilities of nanodiamonds, such as biocompatibility, sensitive magnetometry, and gene and drug delivery.

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Mark A. Zurbuchen, Michael P. Lake, Sirus A. Kohan, Belinda Leung, Louis-S. Bouchard. 2015-06-21. Nanodiamond Landmarks for Subcellular Multimodal Optical and Electron Imaging. https://doi.org/10.1038/srep02668

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