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Updated: Aug 24, 2026

Rigid Embedding of Fixed and Stained, Whole, Millimeter-Scale Specimens for Section-free 3D Histology by Micro-Computed Tomography
Published on: October 17, 2018
AFM of biological material embedded in epoxy resin
Nadezda Matsko1, Martin Mueller
1Electron Microscopy, Institut fuer Angewandte Physik, ETH-Hoenggerberg, CH-8093 Zuerich, Switzerland.
Abstract:
We present a simple method to extract morphological details from the block face of epoxy embedded biopolymers by AFM. It is shown that topographical contrast and the identification of small structural details critically depend on the procedure of sample preparation before embedding (chemical fixation or high-pressure freezing and freeze-substitution) and on the hardness of the embedding epoxy resin. Ethanol treatment of the block face of the sample after microtomy elutes non-cross-linked polymer chains and makes the smallest details of the embedded biomaterial amenable to detection. AFM (height and phase contrast) examination of the block face of accordingly prepared cells of Caenorhabditis elegans provides data that are comparable to TEM.
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