Ultracentrifugation


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The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Ultracentrifugation

 

a method of separating and studying high-molecular-weight compounds, viruses, and subcellular particles using an ultracentrifuge. The idea of ultracentrifugation was proposed by A. V. Dumanskii in 1913. However, the development of the modern theory of sedimentation analysis was not possible until 1926, when T. Svedberg built the first high-speed ultracentrifuge, which could achieve an acceleration of 105g.

There are two types of ultracentrifugation: preparative and analytical. Preparative ultracentrifugation is used to fractionate and isolate biopolymers in quantities sufficient for practical purposes. It is widely used in the density gradient of saccharose, glycerin, and dextrin solutions; it permits the separation of a mixture into individual components, differentiated by the effective mass and frictional coefficient of particles and molecules. Zonal and continuous-action rotors have made it possible to increase substantially the volumes of solutions of fractionated particles and consequently to purify flu viruses during the preparation of vaccines.

Analytical ultracentrifugation is used to study the homogeneity (purity) of biopolymer preparations, such as proteins, nucleic acids, and polysaccharides, and to determine the sedimentation rates, molecular weights, dissociation constants, and size of macromolecules.

Ultracentrifugation is used in medicine for clinical diagnosis, the preparation of blood substitutes, and other purposes.

REFERENCES

Shpikiter, O. V. “Metody issledovaniia biopolimerov s pomoshch’iu analiticheskoi ul’tratsentrifugi.” In Sovremennye metody v biokhimii. Moscow, 1964.
Bowen, T. Vvedenie v ul’tratsentrifugirovanie. Moscow, 1973. (Translated from English.)
Schachman, H. K. Ultracentrifugation in Biochemistry. New York-London, 1959.

N. N. CHERNOV

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
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