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Updated: Jul 16, 2026
07:33
Biological Sample Preparation by High-pressure Freezing, Microwave-assisted Contrast Enhancement, and Minimal Resin Embedding for Volume Imaging
Published on: March 19, 2019
Electron holography of biological samples.
P Simon1, H Lichte, P Formanek
1Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Strasse 40, 01187 Dresden, Germany. simon@cpfs.mpg.de
Micron (Oxford, England : 1993)
|March 22, 2007
Summary
Off-axis electron holography offers advanced imaging of unstained biological samples, overcoming previous resolution limitations. This technique is crucial for visualizing nanoscale fields in biological systems.
Area of Science:
- Electron microscopy
- Biophysics
- Materials Science
Background:
- Off-axis electron holography (OAEH) development for biological samples began in 1986.
- Interest waned in the 1990s due to resolution and contrast limitations compared to conventional methods.
- The field remains niche, with limited publications on biological applications.
Purpose of the Study:
- To review the development and applications of OAEH in biological imaging.
- To present new findings on collagen fibers and bacterial S-layer 2D crystal lattices.
- To provide a comprehensive overview including related techniques and materials.
Main Methods:
- Review of historical development of OAEH for biological samples.
- Application of OAEH to unstained biological specimens like viruses and bacteria.
- Discussion of in-line holography and OAEH for biomaterials.
Main Results:
- OAEH has been applied to various biological structures including ferritin, viruses, and bacterial components.
- New results on collagen fibers and bacterial S-layer 2D crystal lattices are presented.
- The review covers a range of biological and biomaterial applications.
Conclusions:
- OAEH is a developing technique with potential for high-resolution imaging of biological systems.
- Overcoming previous limitations allows for new applications in visualizing biological structures.
- Further research can expand the use of OAEH in biophysics and related fields.
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