Chromatography (from Greek chroma – color + grapho – to write) is a number of methods for chromatographic separation of substances, in which sample components are distributed between two phases, one of which is stationary and the other is a mobile one. The stationary phase can be solid or liquid, deposited on a solid carrier or gel. It can be put into a column, distributed as a layer or a film. The mobile phase may be a liquid or a gas or a fluid (gas in the supercritical state).
Separation can be based on adsorption, distribution, ion exchange, combination, etc., or on differences in physical and chemical properties of molecules (size, mass, volume, etc.).
Chromatography can be used for obtaining pure substances in quantities sufficient for further use (so-called Preparative Chromatography ), for qualitative and quantitative determination of separated components (Chromatographic analysis), and to determine the physical and chemical characteristics of the separated components.
Chromatographic systems are classified by the phase aggregation state (gas – liquid, gas – solid, liquid – solid, liquid – liquid), the chromatographic system geometry (column and planar system), the mechanism that underlies the equilibrium distribution between mobile and stationary phases (distribution between the two fluids, adsorption of liquid on a solid surface, ion exchange) and others.
Chromatography was introduced by Michael Tsvet in 1901, however, the rapid development of various types of chromatography started only in the 30s of the twentieth century.
In 1931, Richard Kuhn, Edgar Lederer, and Alfred Winterstein isolated by chromatography ? and ? fractions of the crude carotene demonstrating the value of the preparative method.
In 1941, Richard Laurence Millington Synge and Archer John Porter Martin developed a new type of chromatography, which was based on the difference in the coefficients of a shared substance distribution between two immiscible liquids. The method was given a name of partition chromatography.
In 1947, was developed a method of ion-exchange chromatography.
In 1952, Martin and Synge were awarded the Nobel Prize in chemistry for creating a method of partition chromatography.
From the middle of XX century to the present day chromatography has intensively developed and became one of the most widely used analytical techniques.
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