Free Thin-Layer Chromatography of Plant Pigments revision notes for OCR A Level Biology – covering specification point 5.2.1 (cii).
Thin-layer chromatography (TLC) is used to separate and identify photosynthetic pigments from plant extracts.
The technique separates pigments based on their solubility in the mobile phase and their affinity for the stationary phase.
The diagram below shows the distribution of typical pigments on a TLC plate that can be extracted from photosynthetic plant tissue:
To calculate the Rf value for each pigment, we use the following equation:
Rf = Distance moved by pigment ÷ Distance moved by solvent front
