Vitreous ice and electron microscopy!

Vitrification of metallic melts to form metallic glasses and to study their properties is a favourite experiment for many in the Department (and elsewhere too). But I never thought about vitreous ice (though I knew about the many different crystalline forms of ice). Apparently, according to this PNAS profile,

When water is suddenly cooled to temperatures below –140°C, by careful methods such as plunging it into a bath of liquid nitrogen, it forms an amorphous structure that is more like a glass than a crystal.

which is not too different from how metallic melts are vitrefied. And, what is more,

Called vitreous ice, this substance cannot be found in nature but can be used to preserve samples for use with an electron microscope. When biophysicist Chikashi Toyoshima first heard of this technique in graduate school at the University of Tokyo, he knew immediately it was a powerful tool to help reveal the structure of biological samples that would otherwise be crushed in the vacuum of electron microscopes. He traveled across the Pacific to learn the technique in California and eventually used the technique to determine the structure of membrane proteins in tubular crystals, providing images of these biological structures for the first time.

I found the profile very, very interesting — along the way, I also learnt a bit about electron microscopy of proteins. Have fun!

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4 Responses to “Vitreous ice and electron microscopy!”

  1. santonu Says:

    yes i saw it from other sourses too. quite interesting. Biologist will benefit from it, i guess. disorder is always interesting

  2. ruth, dundee student Says:

    hey! this website’s coolio!
    im a 4th year undergrad at the university of dundee in scotland, and we just had a tour of our microscopy facility-its rekindled my enthusiasm after weeks of pounded knowledge 😦
    also a good description to help me in my exam 🙂

    thanks!

    (i’ve been called a high entropy area-my lab work is a bit…dubious)

  3. Trio behind method to visualise the molecules of life wins 2017 Nobel Prize in Chemistry Says:

    […] Cryo-electron microscopy eliminates the need for dehydration. Biological samples such as cells, viruses or proteins are simply frozen within the liquid they are in. As long as we keep the sample frozen in the microscope, the ice protects it from the harsh effects of the vacuum. However, we can’t form just any type of ice. It must be vitreous ice. […]

  4. Cryo-EM takes centre stage | James Streetley Says:

    […] Cryo-electron microscopy eliminates the need for dehydration. Biological samples such as cells, viruses or proteins are simply frozen within the liquid they are in. As long as we keep the sample frozen in the microscope, the ice protects it from the harsh effects of the vacuum. However, we can’t form just any type of ice. It must be vitreous ice. […]

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