Chromatography is a method for separating a sample. It tends to be coupled with mass spectrometry. There are several different chromatography types, including gas chromatography and paper chromatography. Tswett is recognized for developing the technique of chromatography. He used petroleum ether and the pigments in green leaves. Depending on the solubility of the pigments in the petroleum ether, they would separate from the solution at different rates.
Martin and Synge used the same concept to find “an alternative physical basis for chromatography.” Together they developed partition chromatography, a method using two solvents instead of one. Using two solvents allows for separating out some compounds with one solvent which may not work with all of the compounds, and then separating out other compounds with the second solvent.
Some of the other methods used today include ion-exchange chromatography and gas-liquid chromatography.
Ambose, D. and Ambrose, Barbara A. Gas Chromatography. George Newnes Limited: London, 1963.
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