Location of separated substances

The success of a chromatographic separation depends ultimately on the location process. Coloured substances are, of course, visible as separate spots at the end of the run. Colourless ones require chemical or physical detection. 

Coating Dominant Substances Solvent system Method of location Remarks 

Silica Adsorption Amino acids 1. BuOH/AcOH/HjO (4 1 1) 2. PhOH/HjO (3 1) Ninhydrin or densitometer Two-way development 

Alumina Adsorption Amino acids BuOH/EtOH/HjO Ninhydrin  

Kieselguhr Adsorption Disaccharides PrOH/EtOAc(65 35) Q-Naphthol-sulphuric acid  

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Location of separated substances on thin layers is done in the same way as it is on paper, but more reactive reagents, for example, concentrated sulphuric acid, can be applied on thin layers, provided that the thin layer material is an inert substance such as silica gel or alumina. 

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