Spinach Alternative
Taken from Teacher Advice Pages at NSTA.org
Question: Other than spinach,is there any other better option for a variety of pigments to run a paper chromatography? If there is, which is the best solvent to be used for this technique? I would like to use it to introduce photosynthesis and pigments to 10th graders.
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Evelyn MontalvoMayaguez, Puerto Rico2005-11-07-->
Answer: The fun part of chromatography is that almost anything works. I've found geraniums are rich and work well. Ethyl alcohol is the only safe solvent. (Avoid petroleum ether, despite the fact that older manuals list it. It's explosive.)
Try the same leaves in both alcohol and water. Anthocyanins (the reds and blues in fall leaves) are water soluble, so you'll get great variety. (Then try to see if the red and blue pigments can be used as indicators. Flowers make great pH meters when mashed.)
Juliana Texley NSTA Web Field Editor Boca Raton, Florida 2005-11-07
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