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Chromatography

               An analytical technique which is used for the isolation, identification and separation of compounds based on differences in affinity for a stationary phase and a mobile phase. In chromatography, the stationary phase may be a solid, liquid, gel or a solid/liquid mixture.. and mobile phase may be a liquid or a gas. 


Principles of Chromatography

"A mixture of compound is allowed to pass through two phases called stationary phase and mobile phases, the separation of compounds can be seen according to their Resolution Front (Rf) values. " Basically it is adsorption and partition. 
The Resolution front (Rf) value is defined as the ration of distance traveled by the sample solute divided by distance traveled by the solvent front. 
During chromatographic separation, there are two interactions occur..
1. Adsorption: separation can be achieved by the differential adsorption of substances by the mobile and stationary phases. 
2. Partition: when a solute is dissolved in two immiscible liquids of equal volume, the ration of its concentration in two phases at a given temperature and equilibrium is called partition coefficient. 

Types of Chromatography
(Click on the type of chromatography to know the details)

6) Gas-Liquid Chromatography (GLC)
7) High Performance Liquid Chromatography (HPLC) 

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