extracting pigments

• chlorophyll a

  yellow-green colour
• chlorophyll b

  blue-green colour
• photosystems

  multisubunit complexes that contain a variety of photosynthetic pigments
• location of photosystems

  thylakoid membrane
• thin layer chromatography process

  tear a leaf into small fragments

  grind with sharp sand and propanone

  transfer a sample of the extract to a watch glass

  evaporate all moisture using a hairdryer

  add a few drops of propanone to dissolve the pigments

  draw a pencil line on the TLC strip 10 mm away from the end and place a small concentrated dot of the pigment on the line

  place in a tube with the base dipping into a running solvent

  remove when finished
• stationary phase material in TLC

  silica gel
• hold TLC plates by the edges

  not contaminated by oil droplets on the surface of the skin
• plate does not touch the sides of the jar

  so condensation on the sides of the jar do not impact the movement of pigments
• why should you work quickly when grinding the leaves and adding propanone

  so the propanone doesn't evaporate