Sciencemadness Discussion Board

DIY TLC plate indicators

coherent - 27-6-2023 at 18:07

Given that commercial TLC plates are absurdly expensive, I've long been wondering how easy it would be to just make my own using microscope slides or similar as a backing material.

However to make the plates more useful I'm interested in what are some good options for indicators, especially those that would be suitable for DIY use in TLC plates.

Does anyone have any suggestions that would be suitable for an inexperienced individual ie: not horribly toxic, straightforward preparation, easily acquirable?

Rainwater - 27-6-2023 at 18:39

Zinc sulfide doped with other metals has a nice glow and is suggested in many videos on the subject
I havent got it to work with copper yet, it glows under blacklight but not in the dark.

Sulaiman - 27-6-2023 at 21:02

If you master the deposition of ZnS on glass
then I suggest as a side project: make a spinthariscope
https://en.wikipedia.org/wiki/Spinthariscope

241Am from a smoke alarm, ZnS screen, magnifying glass in a dark room.
.... Fascinating

Rainwater - 28-6-2023 at 01:40

I can not find the exact procedure I was attempting.
It was based on a video

I think 1g of ZnS is added to a test tube and barely covered with water
Then 1g of CuSO4*5H2O was disolved to 1L of water, then 0.5mL or some very small amount was added to the ZnS powder. The tube is capped and shaken until mixed and dried.
After the waters gone its fired to almost melting while protected from oxygen.

The powder will glow under uv and the copper is supposed to make it glow in the dark.
Found it.
https://m.youtube.com/watch?v=NGdVCIGHeQE

Just add a small amound if the doped ZnS or whatever dye you select to your tlc mix and then
https://m.youtube.com/watch?v=pNDQkM3jasA

Fulmen - 28-6-2023 at 02:54

Don't dismiss stains like iodine, KMnO4 or sulfuric acid. Some are a bit compound specific but that can sometimes be utilized for better separation.

coherent - 28-6-2023 at 05:15

Quote: Originally posted by Sulaiman  
If you master the deposition of ZnS on glass
then I suggest as a side project: make a spinthariscope
https://en.wikipedia.org/wiki/Spinthariscope

241Am from a smoke alarm, ZnS screen, magnifying glass in a dark room.
.... Fascinating


Oh wow, that is a very cool little gadget. I'll definitely be keen to try it out should I ever have the skills for it.

coherent - 28-6-2023 at 05:16

Quote: Originally posted by Rainwater  
I can not find the exact procedure I was attempting.
It was based on a video

I think 1g of ZnS is added to a test tube and barely covered with water
Then 1g of CuSO4*5H2O was disolved to 1L of water, then 0.5mL or some very small amount was added to the ZnS powder. The tube is capped and shaken until mixed and dried.
After the waters gone its fired to almost melting while protected from oxygen.

The powder will glow under uv and the copper is supposed to make it glow in the dark.
Found it.
https://m.youtube.com/watch?v=NGdVCIGHeQE

Just add a small amound if the doped ZnS or whatever dye you select to your tlc mix and then
https://m.youtube.com/watch?v=pNDQkM3jasA


Perfect! thanks for the assist

coherent - 28-6-2023 at 05:18

Quote: Originally posted by Fulmen  
Don't dismiss stains like iodine, KMnO4 or sulfuric acid. Some are a bit compound specific but that can sometimes be utilized for better separation.


Seems like variety would be the best approach, many seem to work well with aromatic rings but beyond that scope I'd imagine that the more options the better.

KMnO4 seems like a good candidate given it's quite easily acquirable (here in Australia anyway...), will have to start building a collection I think.