Paper Chromatography of Plant Pigments….
Exciting, isn’t it?
Paper chromatography, in a nutshell, is separating the
mixture of a plant so you can easily identify the components. It is a form of
partition chromatography. And since I am merely a freshman and my mum did this
stuff back when she was a junior or senior, I had to look it up. I read that it
had something to do with the division of the solutes that I used between two
liquid phases. Still kind of confusing and that is why I decided to try out the
experiment. I got an outline of the experiment from Source #3 and I just got to
work on it.
So what this experiment was showing me was extracting the
pigments in a plant’s leaves by the process of paper chromatography. I started
with chopped up pine tree needles (since it’s winter I couldn’t find any nice
green coniferous leaves). Now I regret to say I didn’t measure anything in this
process because frankly, I’m just too darn lazy. I put the itsy-bitsy pieces of
the needles, put them in a jar, and just barely covered it with some 91%
Isopropyl Alcohol. Then I put a lid on the jar and stuck it in some hot water
for half an hour. Yep! And since nobody would answer quick enough on Yahoo
& I couldn’t find it on Google, I asked my mum. She assumed that the heat
of the water was helping to extract the chlorophyll from the tree’s needle and
put it in the alcohol. Then afterward I took my great uncle’s coffee filters
and cut some strips and put one end in the alcohol + pine needles and the other
end outside the jar. Honestly though, I’m pretty darn sure I did something
wrong. But I don’t know what it’s originally supposed to look like so I can’t
tell.
So finally after letting some of the alcohol evaporate I
took out the oh-so-lovely coffee filter strips and there were mysterious lines
(which was the whole point of this in the first place) but the problem was that
I had no idea what they were. So when in doubt…. Google. Thousands of websites
but Source #1 gave me “In this process, various pigments will separate along
the chromatography paper depending on polarity of the pigments. The most polar will be in the lowest band on
the paper, while the least polar will be in the uppermost band.” Well yeah,
thanks for the help! Because I totally understand that… well I go back to
Google. I learned…. Nothing actually. I searched for an hour and I couldn’t learn
a single thing. But I have a feeling that I will learn about it in class so no
worries there.
Paper chromatography is pretty darn cool. It’s amazing
how some of the lines will form depending of polarity (which I still don’t know
what that is). All in all, I think my experiment showed to be a success. It
taught me something and the most amazing thing is that I think I actually
preformed it correctly! Yes, I do kind of feel on top of the world right now.
Sources:
1)
http://faculty.southwest.tn.edu/jiwilliams/Paper%20Chromatography.htm
2)
http://www.answers.com/topic/paper-chromatography\
3)
http://chemistry.about.com/cs/howtos/ht/paperchroma.htm
4)
http://medical-dictionary.thefreedictionary.com/paper+chromatography
5) http://www.google.com