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Biological serial block face scanning electron microscopy at improved z-resolution based on Monte Carlo model.

ABSTRACT: Serial block-face electron microscopy (SBEM) provides nanoscale 3D ultrastructure of embedded and stained cells and tissues in volumes of up to 10⁷?µm³. In SBEM, electrons with 1-3?keV energies are incident on a specimen block, from which backscattered electron (BSE) images are collected with x, y resolution of 5-10?nm in the block-face plane, and successive layers are removed by an in situ ultramicrotome. Spatial resolution along the z-direction, however, is limited to around 25?nm by the minimum cutting thickness. To improve the z-resolution, we have extracted depth information from BSE images acquired at dual primary beam energies, using Monte Carlo simulations of electron scattering. The relationship between depth of stain and ratio of dual-energy BSE intensities enables us to determine 3D structure with a ×2 improvement in z-resolution. We demonstrate the technique by sub-slice imaging of hepatocyte membranes in liver tissue.

SUBMITTER: He Q

PROVIDER: S-EPMC6113311 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Biological serial block face scanning electron microscopy at improved z-resolution based on Monte Carlo model.

He Q Q Hsueh M M Zhang G G Joy D C DC Leapman R D RD

Scientific reports 20180828 1

Serial block-face electron microscopy (SBEM) provides nanoscale 3D ultrastructure of embedded and stained cells and tissues in volumes of up to 10<sup>7</sup> µm<sup>3</sup>. In SBEM, electrons with 1-3 keV energies are incident on a specimen block, from which backscattered electron (BSE) images are collected with x, y resolution of 5-10 nm in the block-face plane, and successive layers are removed by an in situ ultramicrotome. Spatial resolution along the z-direction, however, is limited to aro ...[more]

PMID: 30154532

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Dataset Information

Biological serial block face scanning electron microscopy at improved z-resolution based on Monte Carlo model.

Publications

Biological serial block face scanning electron microscopy at improved z-resolution based on Monte Carlo model.

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