Electron Microscopy lab
The Electron Microscopy lab of the Center for Anatomy and Cell Biology offers a wide range of preparation and imaging methods for examining ultrastructures of tissues and cells.
The imaging of biological samples is realized by transmission electron microscopy (TEM) and TEM tomography. Depending on the size and type of sample, conventional fixation as well as cryofixation can be used.
Both internal and external services are available on a collaborative basis. For an individual project design and information on usage fees, please contact us (Dr. Andy Sombke).
Analysis of the internal structure of tissues and cells can be performed using transmission electron microscopy, which provides two-dimensional images. This requires ultra-thin sections of samples (usually 50 nm) into which electrons can penetrate. In addition, 3-dimensional imaging can be achieved by stepwise rotation (80°) of the sample grid (so-called TEM tomography).
The Transmission Electron Microscope Tecnai G20 can visualize objects with a typically up to 100,000 x magnification (higher magnifications dependent on specimen quality) with an accelerating voltage of 20-200 kV. For digital imaging, the TEM is equipped with a 4k CCD camera.
Our lab is equipped with:
- Leica EM AFS1 (Baltec HPM-010) for cryofixation
- Pelco BioWave Pro+ fixation microwave
- Leica ACE 200 for carbon coating
- High-speed milling system before ultramicrotomy using Leica Ultratrim
- Leica Ultracut S and 7 for semi- and ultra-thin microtomy
- Leica Ultracut 7 with Leica EM FC7 for cryo-microtomy
- 200 kV Tecnai G2 20 (FEI) transmission electron microscope with TEM tomography option (with an FEI Eagle 4K CCD camera) for imaging and acquisition
Our established protocols include:
- conventional chemical fixation for tissue samples, organoids, 3D cell culture samples and cell monolayers
- High pressure freezing and freezer replacement for high quality cell preservation
- Negative staining for the visualization of e.g. B. macromolecules and bacteria
- semi- and ultra-thin microtomy of resin-embedded specimens
Service and cooperation
As a service and cooperation unit, we provide the complete workflow from fixation and embedding of samples over sectioning and contrasting up to imaging of samples.
Moreover, we are equipped with workststions for image analysis and 3D reconstruction (Amira).