Chromatography Forum

TO Mr Krickos
I have already try the preeluting plat, however the black line still appeared. As you stated before about my work concerning the spot might be submerged in the mobile phase, I think it was not the problem because we have tried to work properly. Nowadays, I become believe that it may be caused by the purity and interaction of the mobile phase, Mr.

i know that it is a crazy question
but are you drawing the plate?
many do this by drawing a pencil line on the plate to create a grid for the samples and the sample loading position

There is no crazy question Mr/Mrs/Ms unmgvar =D
Absolutely not.
However, is it does a matter by drawing the line by pencil since the carbon of pencil absolutely doesnt have any chromophores to give any absorbance. Thank you before.

Is your black line disappearing when you dry the plate? That is, are you talking about separation of mobile phase, as I remember that Tom mentioned already?
Incidentally, what makes you think that a black substance, as in pencils, "absolutely" does not have a chromophore??