Chromatography is a biochemical technique in which the components of a mixture are separated based on their differential migration. In this method the various biomolecules such as amino acids, fatty acids, carbohydrates, etc. can be separated and identified.
Chromatography was devised by Tswett in 1906. Originally he separated coloured substances from the extracts of leaf and hence it was called chromatography (chromac= colour, graphein to write).
The procedure of separation is called chromatography. The preparation is called chromatogram. The mixture to be separated is called solute.
Chromatography involves two main phases or media, namely a stationary phase and a Mobile phase.
The stationary phase is a liquid or gas. The solute to be separated is adsorbed into the Stationary phase, The mobile phase is called the solvent system. It consists of a mixture of butanol, water and acetone. The solvent has lesser affinity to the stationary phase and it carries the components Of the solute across the stationary phase.
Principles of Chromatography
In chromatography the components of a mixture are separated based on two factors.
1. Different rates of migration of the components of a mixture on the solvent system.
2. Different rates of adsorption of the components in the stationary phase.
Types of Chromatography
The chromatography is of two types, namely adsorption chromatography and partition Chromatograph
In adsorption chromatography, the stationary phase is solid. Eg. Finely divided silica gel or alumina. The mixture to be separated is adsorbed into the adsorbent. The mobile phase, is a liquid or gas.
Partition chromatography is commonly used. In partition chromatography the stationary phase is a liquid and the mobile phase is a liquid or a gas.
- Paper Chromatography
- Thin layer Chromatography
- Column Chromatography
- Gas Chromatography
- Ion Exchange Chromatography
- High Performance Liquid Chromatography (HPLC)
