Definitions for cryofixation
cry·ofix·a·tion

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1. cryofixationnoun

   The freezing of a specimen by immersion in liquid nitrogen

WikipediaRate this definition:0.0 / 0 votes

1. Cryofixation

   Cryofixation is a technique for fixation or stabilisation of biological materials as the first step in specimen preparation for electron microscopy and cryo-electron microscopy. Typical specimens for cryofixation include small samples of plant or animal tissue, cell suspensions of microorganisms or cultured cells, suspensions of viruses or virus capsids and samples of purified macromolecules, especially proteins.Cryo fixation Types 1.Freezing-drying 2.Freezing-substitution 3.freezing-etching

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1. Cryofixation

   Cryofixation is a technique for fixation or stabilisation of biological materials as the first step in specimen preparation for electron microscopy. Typical specimens for cryofixation include small samples of plant or animal tissue, cell suspensions of microorganisms or cultured cells, suspensions of viruses or virus capsids and samples of purified macromolecules, especially proteins. The method involves ultra-rapid cooling of small samples to liquid nitrogen temperature or below, thus stopping all motion and metabolic activity, and preserving the internal structure by freezing all fluid phases solid. The ultimate objective is to freeze the specimen so rapidly that ice crystals are unable to form, or are prevented from growing sufficiently large to cause damage to the specimen's ultrastructure. The formation of samples containing specimens in amorphous ice is the holy grail of biological cryomicroscopy. However, in practice, it is very difficult to achieve high enough cooling rates to produce amorphous ice in specimens more than a few micrometres in thickness. For this purpose, plunging of a specimen into liquid nitrogen at its boiling point does not always produce sufficiently rapid freezing, for several reasons. Firstly, the liquid nitrogen boils rapidly around the specimen forming a film of insulating N2 gas that slows heat transfer to the cryogenic liquid, known as the Leidenfrost effect. Cooling rates can be improved by pumping the liquid nitrogen with a rotary vane vacuum pump for a few tens of seconds before plunging the specimen into it. This reduces the temperature of the liquid nitrogen below its boiling point, so that when the specimen is plunged into it, for a brief period of time it envelops the specimen closely, and extracts heat from it efficiently. Even more rapid cooling can be obtained by plunging specimens into liquid propane or ethane cooled very close to their melting points using liquid nitrogen or by slamming the specimen against highly-polished liquid nitrogen-cooled metal surfaces made of copper or silver. Secondly, two properties of water itself militate against rapid cryofixation in large specimens. The thermal conductivity of ice is very poor compared with that of metals, and water produces an exothermic release of latent heat of fusion as it freezes, defeating rapid cooldown in specimens more than a few micrometres thick.

How to pronounce cryofixation?

1. Alex

   US English

   David

   US English

   Mark

   US English

   Daniel

   British

   Libby

   British

   Mia

   British

   Karen

   Australian

   Hayley

   Australian

   Natasha

   Australian

   Veena

   Indian

   Priya

   Indian

   Neerja

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   Zira

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   Oliver

   British

   Wendy

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   Fred

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   Tessa

   South African

How to say cryofixation in sign language?

Numerology

1. Chaldean Numerology

   The numerical value of cryofixation in Chaldean Numerology is: 9

2. Pythagorean Numerology

   The numerical value of cryofixation in Pythagorean Numerology is: 6

References

1. ^ Wiktionary
   https://en.wiktionary.org/wiki/Cryofixation
2. ^ Wikipedia
   https://en.wikipedia.org/wiki/Cryofixation
3. ^ Wikidata
   https://www.wikidata.org/w/index.php?search=cryofixation