Isolation by Planar Chromatography

Planar liquid chromatography (PLC) involves the separation of mixtures on thin layers of adsorbents that are usually coated on glass, plastic, or aluminium sheets. The most common form of planar liquid chromatography is thin-layer chromatography (TLC); and this particular technique is the easiest, cheapest, and most widely used method for the isolation of natural products. TLC is one of the oldest forms of chromatography, the simplest example being the school experiment of spotting a plant extract near the bottom of thin strips of blotting paper and “developing” in a jar with water or alcohol. As the water moves up the blotting paper, the dark extract is separated into its component colors of light and dark greens and yellows.