Thin-layer chromatography (TLC) is a
chromatography technique used to separate non-volatile mixtures. Thin-layer chromatography is performed on a sheet of glass, plastic, or aluminium foil, which is coated with a thin layer of
adsorbent material, usually
silica gel,
aluminium oxide (alumina), or
cellulose. This layer of adsorbent is known as the
stationary phase.