Paper chromatography is a molecular separation technique and is generally used to separate colored chemicals and substances. It works on the mobility of different molecules as they move from a stationary phase to a mobile phase. Generally, a piece of high quality filter paper serves as the stationary phase and developing solution is the mobile phase that moves up the filter paper. The molecules are separated by the distance traveled on the filter paper.
It was first used by Roman, who used gall nut extracts impregnated into paper to determine ferrous sulfate and copper acetate. This method was also used to stain the togas by snail pigments. In 1903, Tswett used paper chromatography to separate out chlorophyll.
It is a simple and reproducible technique and is commonly used as a teaching tool.
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