Electron Optic Documents

JEOL Resources


Documents of interest in support of your JEOL product

Cryo Block for SEM


Cryo-SEM imaging is a powerful tool in studying the structures of electron beam and vacuum sensitive materials. These materials include: fragile biological structures such as fungi, plants, cells, etc. as well as soft or volatile samples and even liquids. Cryo-SEM offers some clear advantages by rapidly freezing a sample prior to imaging, thus maintaining the sample as close as possible to its natural state. Long dehydration and chemical fixation steps can be avoided. Inhibiting dehydration helps maintain delicate structures without shrinkage. Moreover, volatile or even liquid samples are stabilized under the electron beam. Cryo fracturing techniques allow for study of the internal microstructure of these types of vulnerable materials as well. A few of the disadvantages are that for efficient freezing, the sample size must be small and the price may not be in everyone’s budget for a state-of-the-art cryo system with freezing station, cold stage, vacuum transfer system etc.

Figure 1: Polymer screws isolate cryo-stub from holder

A low cost alternative to a complete cryo-system that has been demonstrated to provide good results for many applications is a simple Cryo Block. The technique is a simple and cost effective means of looking at fully hydrated materials or other electron beam and vacuum sensitive samples. It involves pre-freezing a Cryo Block in liquid nitrogen and then contact freezing the sample prior to placing it in the SEM. The advantage of this technique is that it is simple, cost effective and the sample will in situ freeze dry in the SEM. The disadvantage is that there is no temperature control and the sample will in situ freeze dry inside the SEM.

The supplies you’ll need are a thermos container or something suitable to put a small amount of liquid nitrogen in, a Cryo Block and cryo-glue or clamps to fix your sample to the stub.

The sample preparation procedure is as follows:

  1. Immerse the Cryo-Stub in liquid nitrogen and let it equilibrate
  2. Once fully cooled, remove the Cryo-Stub and quickly contact freeze your sample and place inside the SEM
  3. Image as normal. It is helpful to insulate your cooled brass block from the basic holder –simple teflon screws or spacers would provide such insulation.

Figure 2: Orchid- Stigma anther

Figure 3: Sour cream

Attached Files
Showing 0 Comment

Comments are closed.

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