Jor - 18-4-2011 at 13:10
Soon I'll recieve some TLC plates.
I see everyone use mixtures of hexanes and ethyl acetate as the mobile phase. However, i do not have any more ethyl acetate (I will get hexanes). Can
I just replace the EtOAc with IPA/DCM/Et2O or any of my other solvents?:
http://www.sciencemadness.org/talk/viewthread.php?tid=16016
I rather not waste acetonitril on this.
smuv - 20-4-2011 at 13:37
Yes. You can and should try a wide array of solvents to get the separations you need. In the home lab, my go to is heptane/DCM for not so polar
compounds and DCM/MeOH for the polar stuff (although this is a fickle system, very easy to overshoot polarity and shoot everything off the plate).
At work my go to's are: Hexanes/DCM or Hexanes/Chloroform for non-polars and Hexanes/Ethyl acetate or DCM/Ethyl acetate for polars. For amines I
often add a drop of TEA to the eluent especially when working with DCM or ethyl acetate systems.
Based on what you are saying, hexanes/DCM should cover your non polars and DCM/Et2O and DCM/IPA should cover your polars. Go easy on the ether and
IPA, they both really tend to move things (ether generally pushes things further than EtOAc for reference). But don't limit yourself to these
solvents...play around with systems, go wild. 
Edit: also make sure that you use pure solvents, a little methanol in recycled DCM for example can make it SOOO much more polar. You will notice it
in the separations.
[Edited on 4-20-2011 by smuv]