best solvent for paper chromatography of amino-acids

sorry for posting this when there are already threads on it, but I can't find exactly what I want.

BTEC requires paper chromatography with a good separation result. The teachers report they can never get this to work well. (They use it to show how TLC is better, but unfortunately the unit requires good paper results).
I think several solvents have been tried but the one on file here is petroleum ether : propanone 2:1. I don't know the concentrations of the aminoacids used (or whether they were fresh - I suspect at least recently they have been kept kept year to year in the chem store, ventilated but not cold). Then ninhydrin spray in a fume cupboard with a hotplate. But they just got big blobs of colour, not clean small spots.
The thing is, I have done this at another place a few years ago and remember getting pretty good results, but with a different solvent, and freshly made solutions from powder, only used for those few days then made fresh each time.
I am just interested to know if people can get this to work, and if so what solvent they use, and about their use of aminoacids. If it hasn't worked here in the past then they must have made up fresh solutions at some point, but that doesn't seem to have helped.
Any working method welcome. Guaranteed is a plus!
 
I did this a few days ago following CLEAPSS PP062 document. I went with the ethanol:ammonia:water 8:1:1 running solvent and it worked extremely well on 14 of our 17 amino acids when i tested it. The solvent itself is potent so good ventilation is needed.
 
sorry for posting this when there are already threads on it, but I can't find exactly what I want.

BTEC requires paper chromatography with a good separation result. The teachers report they can never get this to work well. (They use it to show how TLC is better, but unfortunately the unit requires good paper results).
I think several solvents have been tried but the one on file here is petroleum ether : propanone 2:1. I don't know the concentrations of the aminoacids used (or whether they were fresh - I suspect at least recently they have been kept kept year to year in the chem store, ventilated but not cold). Then ninhydrin spray in a fume cupboard with a hotplate.
The thing is, I have done this at another place a few years ago and remember getting pretty good results, but with a different solvent, and freshly made solutions from powder, only used for those few days then made fresh each time. I am just interested to know if people can get this to work, and if so what solvent they use, and about their use of aminoacids. If it hasn't worked here in the past then they must have made up fresh solutions at some point, but that doesn't seem to have helped.
Any working method welcome. Guaranteed is a plus!

Guaranteed in Petroleum Ether:propanone in the ration 9:1 (for Plant Pigments.

For the amino Acids use Butan-1-ol:Acetic Acid:water (60:2515)

concentrations of aa's are 1mg/mL. used the same set for 6 yersm stor in microfuge tubes in the freezer.

Amino acid concentrations 1mg/mLpaper chromatog of spinach pigments.JPG
Picture AA PAPER CHROMATOG 001.jpg
 
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We do this for A level using paper. Solvent is Butan-1-ol : glacial ethanoic: distilled water 4:1:1 I always make the amino acids up fresh every time.
 

CovTech

Lvl 38 Alchemist
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We do this for A level using paper. Solvent is Butan-1-ol : glacial ethanoic: distilled water 4:1:1 I always make the amino acids up fresh every time.
We do this solvent as well
All amino acids are made at 1% solution
 
Thanks all. I assume they have used that solvent in the past, so maybe it was always that the solutions weren't fresh?
I don't know if something happens that makes them spread outwards and smear upwards, rather than rise in a small discrete dot.
Anyway, I will say to do it that way and order some powders for next time they do it.
thanks
 
Thanks all. I assume they have used that solvent in the past, so maybe it was always that the solutions weren't fresh?
I don't know if something happens that makes them spread outwards and smear upwards, rather than rise in a small discrete dot.
Anyway, I will say to do it that way and order some powders for next time they do it.
thanks
To answer your question(s) thar the reason that the samples you spotted spread out, rather than appearing as discrete spots, is due to diffusion and the smearing due to the "tailing effect". You can get (well I and the others I teach this technique to) can get discrete small spots by just touching the paper with a wooden cocktail stick which has been left to soak in a microfuge tube containing the amino acid solution. A nice attempt chemtech25 @chemtech25 :);)
 
Thanks - I will suggest that as well, although I am not sure if spotting with a micro-capillary might not be part of the required process.
 
For our recipe, we're using Chromatography strips suspended in test tubes. The solution is a 3:1:1 (60%, 20%, 20%) of Petroleum Ether, Acetone and distilled water. A finger width of the solution at the bottom of the test tube, then a hole puncher makes 'dots' out of the spinach leaves, which are dropped into the solution.
 
I did this a few days ago following CLEAPSS PP062 document. I went with the ethanol:ammonia:water 8:1:1 running solvent and it worked extremely well on 14 of our 17 amino acids when i tested it. The solvent itself is potent so good ventilation is needed.
What conc ammonia is used please?
 
We do tlc of amino acids,
The amino acid concentration is 0.10M.
There are two versions, for working out a 2 peptide or tripeptide set, each has a different solvent.
one is 8:10:10 ethanol : 880 ammonia : water
the other 4:1:1 N-butanol : glacial acetic acid : water

Both give good The second does give better results with ninhydrin with less background staining (ninhydrin can react with ammonia, just but at a slow rate).
It also smells better despite the butanol as nothing is quite as penetrating as ammonia.
these guys use a similar mix:
 
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