Thin layer chromatography TLC is a quick and inexpensive analytical technique that indicates how many components are in a mixture The chromatography works according to the principle that different compounds have different solubility and adsorption Thin Layer Chromatography TLC is a solid liquid technique in which the two phases are a solid stationary phase and a liquid mobile phase In the TLC technique usually using a plastic sheet or glass which is coated with tin layer of a solid absorbent substance usually it is silica TLC plate is a stationary phase The paper is dipped into solvent which is a mobile phase The solvent dissolves the samples and carries them up the paper The substance unknown can be identified by comparing the horizontal spots Ninhydrin is using for detection of amino acids amines amino sugars Since amino acids are colourless compounds ninhydrin is used for detecting them To identify this after development the TLC plate is sprayed with ninhydrin reagent and dried in an oven Ninhydrin reacts with α amino acids that results in purple coloured spots
