The previous post about DEAE cellulose reminded me of a classic experiment in chromatography: the separation of dyes. This is where the name comes from - even though most of what we separate anymore isn’t colored, it stuck. Mikhail Tsvet, a Russian chemist, used it to separate chlorophylls and carotenes, two classes of brilliantly colored biomolecules. Lucky for you, when I have nothing to do on a Sunday afternoon, I do…well, the exact same thing I do during the week, only for free. In my kitchen. It gets messy. Today wasn’t so bad.

I went to the grocery and bought the regular food coloring everyone gets, the four little plastic bottles with red, blue, green, and yellow. If you look at the ingredients, my box says there is: water, propylene glycol, yellow 5, red 40, and blue 1. Propylene glycol, mentioned on the fomepizole entry, is just a nontoxic alcohol that probably makes the dyes a bit more soluble. Notice there are only three dyes. This is probably not so surprising since we have yellow, red, and blue, and the only one without its own dye is green. Presumably the venerable principle of “yellow and blue make green” is at work here. We set out to verify the YABMG theory.

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Go play outside! See you tomorrow.