Chromatography refers to a method employed in laboratories. It helps in efficient and easy
separation of chemical compounds of mixtures using the adsorption phenomena. The strengths of
this technique are manifested especially in the isomers and natural materials separation.
Tswett, in 1910, first employed this chromatography method in the leaf pigments separation
and the technique instantly achieved rapid growth as it was applied to the carotinoid pigments
separation, among other uses.
The separation method is referred to as ‘column chromatography’, where a glass column
is used to fill with adsorbent and through it passes a composite liquid mixture.
This technique operates in such a manner that each component forms a different section
of the column arranged in distinct colors as per each materials adsorption affinity.
In the column chromatography, adsorbent in proper amount is filled evenly in a vertical
glass column and a liquid mixture is poured into the liquid and column to pass through
the adsorbent. However, each compound at varying heights is absorbed into beds based
on the individual adsorption affinity of each component.
The sections of each component are absorbed, yet may not separate completely. Conversely,
desorbent is poured into the column so that the adsorbed components dissolve and move down in
the column. Thus the components move, but the rates of migration vary as per the adsorption
affinity of each component. The lower layers components move faster and they get separated,
thus this process of column chromatography is known as development.
As the material gets separated and is a pigments mixture, there will appear colored zones and can
be seen at different heights with adsorbent in the column and such colored zones are referred to
as chromatogram. as the stage of development is over, the adsorbent is pushed out, dividing each
zone and thus the absorbates using a desorbent get extracted separately and this process in
known as elution.