[awais]

I have made vanillin solution:
 0.5g of vanillin in 20ml ethanol and 80 H2SO4 and this was warmed to 120°C. Now I don't know how to use this. I tried to dip my TLC in this solution but due to conc. H2SO4 the silica layer starts removing.
Plz guide me that how i can use this or may be i am wrong and what will be effect after applying this solution to TLC

Thanks

[Borek]

I have made vanillin solution:

I assume you needed it for something? Becasue ATM you have posted something like "I have made a solution, how I use it" which sounds like some abstract joke

80 H2SO4

Please elaborate. 80 what of what?

Oh, and for answer you will probably have to wait for some organic chemist

[russellm72]

Hi,

Normally you would make it up in say a 500 ml brown bottle that you can cap and store for a while. Normally as you said you dip your TLC plate in and remove carefully allowing any excess to drip off. The you heat your plate gently with a heat gun and your product spots should appear. It's a nice standard reagent and smells quite sweet too which helps.

Now if you say your silica is falling off it sounds like you have rubbish plates. I hope your not like an undergraduate and the plates are home made cause I remember those days and the silica didn't set well.

Normally I use glass backed or preferably aluminium backed plates that we buy in from a supplier and these pose no problem.

How much c.H2SO4 have you used? You dont need a bucket load.

R.

[movies]

Vanillin stain doesn't have a very long shelf life, relative to other stains, so watch for it starting to go bad.

[awais]

sorry guys, i wrote my question in hurry so misssed somethings. The amount of H2SO4 is 80 mL, which i think is quite high. I read the protocol send by some one(http://www.ux1.eiu.edu/~cfthb/research/handbook/TLCstains.htm). On this protocol the amount of H2SO4 is very less. might be this is problem. For TLC , i m using alumin. back plate and i think it is of good quality. If someone can write me  the procedure of making this vanillin solution.
Thanks

[AWK]

I have made vanillin solution:
 0.5g of vanillin in 20ml ethanol and 80 H2SO4 and this was warmed to 120°C. Now I don't know how to use this. I tried to dip my TLC in this solution but due to conc. H2SO4 the silica layer starts removing.
Plz guide me that how i can use this or may be i am wrong and what will be effect after applying this solution to TLC

Thanks

This reagent is used in an atomizer.

[russellm72]

OK.

Dissolve 15g of Vanillin in ethanol (250 ml). Add c.H2SO4 (2.5 ml).

Thats your recipe and as you see much less c.H2SO4.

R.