The Home Scientist 024 - Making thin-layer chromatography (TLC) plates

How to make thin-layer chromatography plates (TLC plates) for a few cents each that are as good as commercial TLC plates that sell for a dollar or two each. You can use these home-made TLC plates the same way you'd use chromatography paper, but the plates provide sharper separations and require far less analyte. They also lie flat, and are much easier to store for later reference.

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[thecrazychemist]

How uniform is the thickness of the coating, and how can you be sure that all slides are covered to the same thickness. Uniformity is key with TLC plates, and thats largely what you pay for when you buy commercial plates from Merk or Machery-Nagel.

[TheHomeScientist]

@thecrazychemist

Well, if the surface area is the same and you use the same formulation for each batch and you stir the slurry each time and use the same volume for each slide, I'd expect the coating thickness to be at least as uniform as it is on commercial plates.

The plates certainly appear to be uniform, and the results I've gotten with them over the years have been uniform: the same Rf values for the same mobile phase and the same analyte.

[amberpoovey]

I wonder if that is Mr Thompson's newspapers...if so he lives in the Mid Atlantic but probabbly North Carolina judging by the article on the Gov. Easley.

[TheHomeScientist]

@amberpoovey

Yes. A quick Google search on the headline will tell you the paper is the Winston-Salem Journal and the date is Sunday, 23 May.

[mikeysgame]

this is probably not a good idea but can you activate these plates in an oven you heat food in

[TheHomeScientist]

@mikeysgame

Well, I have a convection oven in my lab that's dedicated to lab use, but if I didn't I wouldn't hesitate to use the kitchen over. Both alumina and plaster of paris are of very low toxicity.

[dallasrichar26]

This video went viral on Panama



[joshganga]

How much does the binder affect retention? Is it possible to use this technique, using the same binder, with polymer-based reversed-phase media?

Thanks for the great demo!

[KristoffDoe]

It's worth adding that previously reagents like Dragendorff or ninhydrin mentioned in your previous videos work beautifuly with TLC, giving an extra dimension for identification of substances.

And even without reagents you can make nice separations eg. dyes and inks (which is used in forensic investigations of documents when there's a suspicion of forgery).

[OrgSynthJosh]

Thanks TheHomeScientist, seriously why have I not thought of this before, I am a 4th year organic chem major and do a significant amount of home chemistry, and TLC plates and far too expensive for the layman. Great video, favorited and subscribed, thanks again

[zcuttlefish]

Hey RBT thanks for putting this video up! I use this everyday in lab (along with flash chromatography). I had been wondering what the binding agent was (I would think that the solvents would dissolve the binder). I think it would be cool if you talked a little about the principle of TLC bc most people won't have the solvents, uv lamp, or stains necessary.

Cheers!

[nehorlavazapalka]

Fail, I've accidentaly arrived at this video while having the TLC plate in front of me.