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Updated: May 26, 2026

3D Imaging of Soft-Tissue Samples using an X-ray Specific Staining Method and Nanoscopic Computed Tomography
Published on: October 24, 2019
Chemical contrast in soft x-ray ptychography
Mike Beckers1, Tobias Senkbeil, Thomas Gorniak
1Applied Physical Chemistry, Ruprecht-Karls-University Heidelberg, Germany. beckers@uni-heidelberg.de
Abstract:
The unique strengths of x-ray microscopy are high penetration depth and near-edge resonances that provide chemical information. We use ptychography, a coherent diffractive imaging technique that disposes of the requirement for isolated specimens, and demonstrate resonant imaging by exploiting resonances near the oxygen K edge to differentiate between two oxygen-containing materials. To highlight a biological system where resonant ptychography might be used for chemical mapping of unsliced cells, reconstructions of freeze-dried Deinococcus radiodurans cells at an energy of 517 eV are shown.
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