Plane Chromatography: Paper and Thin‐Layer Chromatography

There is an alternative chromatography technique that may be encountered in the analytical laboratory called plane chromatography. Just as the name suggests, plane chromatography utilizes a flat planar surface as the stationary phase in contrast to column chromatography that uses small spherical particles packed into a column. While the process of paper chromatography gives a good example of plane chromatography, usually the technique of thin-layer chromatography (TLC) is mostly used in the analytical laboratory. In TLC, the process is the same as paper chromatography, but instead of using paper fiber as the stationary phase, usually, silica or alumina is used. The retention factor (also previously called capacity factor) was presented to describe the retention behavior of a compound on a particular column.