What is Chromatography?

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Chromatography

Chromatography is a laboratory technique for the separation of a mixture. 

 The mixture is dissolved in a fluid called the mobile phase,which carries it through a structure holding another material called the stationary phase.The various constituents of the mixture travel at different speeds, causing them to separate. 

The separation is based on differential partitioning between the mobile and stationary phases. 

Subtle differences in a compound's result in differential retention on the stationary phase and thus affect the separation.

Chromatography is based on the concept of partition coefficient. 

Any solute partitions between two immiscible solvents. When we make one solvent immobile (by adsorption on a solid support matrix) and another mobile it results in most common applications of chromatography. If the matrix support, or stationary phase, is polar (e.g. paper, silica etc.) it is forward phase chromatography, and if it is non-polar (C-18) it is reverse phase.

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