THIN LAYER CHROMATOGRAPHY

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 THIN LAYER CHROMATOGRAPHY

It is a chromatographic separation method used to separate mixtures, to check the purity of a mixture, and to monitor the progress of the reaction.


Procedure

  • A glass plate coated with a material of the adsorbent will constitute the stationary phase. The material is made into a slurry or a paste and the glass plate is coated with it by a thin layer applicator and dried.
  • This glass plate with a thin layer of stationary phase is called chromatoplate. The mixture to be separated is applied to one end of the plate and it is placed in the solvent.
  • When the solvent reaches near the top, it is removed and dried. If the components are colored the spots can be readily located.
  • If the components are colorless the dried plate is sprayed with a suitable reagent to make the spot colored.
  • In this way, the position of the components is located and their Rf values are determined.
  • Rf value is the ratio of the distance traveled by a component to the distance traveled by the solvent is known as the Retention factor.
  • Under a given set of conditions, the Rf value is constant for a given component. Hence it is possible to identify the various components by determining their Rf values.

Advantages

  1. It can be used for the separation of minute quantities
  2. Sensitive and sharp separation is possible.
  3. Speed of separation is high.
  4. This method provides a wide choice of stationary phases.

Applications

  1. It is used for the detection of purity of any sample and the identification of compounds.
  2. It is used in the pharmaceutical, food, and cosmetic industries.
  3. It is used for biochemical analysis

Location: United States

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