EXTRACTION AND FLUORESCENCE OF CHLOROPHYLL

NEEDED

     -  Plant sample (spinach, leafs, green tea, ...)
     -  Ethanol (or acetone or nail varnish remover)
     -  UV-light

PROCEDURE

         Cut the sample in peaces and put it in a bit of
     ethanol. As soon as the solvent is green  (1 - 10
     min) it will show a strong red fluorescence
     under UV-light.

COMMENTS

         The extracted molecule is a mixture of
     chlorophyll a and b (R = -CH2 and CHO resp).
         The fluorescence of chlorophyll in the initial
     plant sample is normally not visible, while the
     extract shows a very strong red fluorescence
     indeed.
         The extraction works better, if the plant
     material is mortared. The result looks nicer if
     the plant material is filtered off before
     UV-irradiation. Propanone works better than
     acetone, which works better than ethanol
     (which however is absolutely fine for both
     extraction and fluorescence brightness). And if
     one likes, the two types of extracted chlorophyll
     can be separated by column chromatography.
Extraction of Chlorophyll (left)
and filtered solution (right).

Fluorescence of Chlorophyll in propanone (left) and ethanol (right).