Physical methods with separation of components

In these methods one or more components of the reaction are separately assayed. 

The reaction mixture studied passes through a column containing substance of a suitable steady state phase. The phenomena of adsorption, desorption or dissolution at the column exit delay the various components of the mixture, which are thus separated. It is then, therefore, possible to assay these components. 

This method is used for gases (gas-phase chromatography), liquids (hquid-phase chromatography) and eventually for ions (ion chromatography). 

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