Electron Optic Documents

As seen in IUCrJ Volume 7, July 2020, pages 639-643.

TEM phase plate development was extensively pursued by Prof Nagayama’s lab in Japan for over ten years. Prof Chiu of Baylor College of Medicine has successfully applied the phase plate system on his Omega filtered TEM (JEM-2200FS) to the molecular structure characterization for proteins.

Auto Tuning for HR-STEM for crystalline sample.

High resolution structure determination by electron cryo-microscopy (cryoEM) and Single Particle Analysis (SPA) has progressed to the point where structures can be determined routinely to better than 3Å on a 300 kV microscope. Pioneering efforts have shown that similar results can also be achieved on 200 kV platforms. Similarly, efforts are underway to allow for a structure determination within a single day or even less. Here, we show results from Merk et al. at NIH from the JEOL CRYO ARM™ 200 obtained on beta-galactosidase at 1.8Å resolution1. The 3D map shows surprising details in the map reflecting the high resolution quality of the data.

Micro electron diffraction, or microED, is a technique aimed at solving structures of biological macromolecules by electron diffraction. Barn-storming work by the group from Prof. Gonen showed the impressive impact and promise of this technique1. The technique borrows from X-ray crystallography in that precession techniques are used for data collection and that much of the well-established software for solving structures by X-ray crystallography can be used for microED. However, it differs in a fundamental way in that electrons are used, which, owing to the substantially larger scattering cross-section of electrons with biological matter, means much smaller crystals can be used.

CRYO ARM Bibliography

Cryo-EM has seen an enormous increase in capabilities and potential in recent years owing to a number of technological advances, e.g. direct detector devices and improved scope automation. JEOL released two electron cryo-microscopes in 2017 specifically designed for automated and unattended, continuous operation at 200 and 300 kV, the CRYO ARM™ series. A recent update on both type of CRYO ARMs has the potential of increasing the throughput well beyond the current limit of 20,000 images/day, namely north of 50,000 images/day as well as extending the resolution to nearly true atomic resolution, i.e. 1.2Å.

“Visualize the truth” is a hope of researchers who use various measuring equipment. Researchers who use electron microscopes as well have a desire to observe the real structure. But actually, in experiments using electron microscopes, many problems arise: They include damage regions of the specimen when it is cut for the size suited to observation, artifacts due to the staining that is applied to enhance image contrast, deformation caused by substitution of water to resin for withstanding vacuum exposure, and thermal damage to the specimen with electron-beam irradiation. As a result, the visualization of the real structure in the microscope image becomes increasingly difficult. One recommended solution is to cool the specimen, that is, “Cryo” techniques. This “Cryo Note” introduces some of the diversified cryo-techniques. We sincerely hope your challenge to observe the “real structure” will be solved by “Cryo” methods.

An e-ABF is observable as a "live image" with real-time signal processing of ABF and BF signals and it shows enhanced contrast of light atoms.

The F2 is a new concept of 20-200kV TEM equipped with a Cold FEG. This new generation of multi-purpose electron microscope is designed specifically to meet today’s diversified needs. Transmission electron microscopy gives access to two-dimensional information coming from the sample. The third dimension is available thanks to the tomography technique. The sample is tilted and for each step, an image (TEM, STEM, EDS) is acquired. Then the 3D volume of the sample can be reconstructed. The F2 has a “Dual SDD system”, which is composed of two silicon drift detectors (SDD) with large sensor areas, resulting in a total solid angle of 1.7 sr. The combination of two detectors and their placement around the sample, allows the ability to record EDS information throughout the full tilt series (from -80° to +80°).

rss

Other Resources

  • Image Gallery
    View a selection of electron images
  • FAQs
    See answers from questions often asked about our SEM and Surface Analysis instruments
  • Links & Resources
    View our page of useful and interesting links to various electron microscopy resources
  • Videos
    View some product presentations of our instruments
  • SEM Theory and SEM Training
    Learn about basic theory, physical operation, and practical applications for SEM
    Basics of SEM
    Learn about the basics of scanning electron microscopy
    JEOLink Newsletter
    Several times a year, we publish and send out a newsletter to our customers. They can also be viewed here
    © Copyright 2024 by JEOL USA, Inc.
    Terms of Use
    |
    Privacy Policy
    |
    Cookie Preferences