[BrettBrothers]

Hi all - I am a graduate student researcher working on lipid chemistry.  For my work, I need to separate a lipid sample into its various constituents using TLC.

I have been using Uniplate Silica Gel G 500 micron plates as the 250 micron plates worked well for me.  I needed to use the larger plate to have more sample for further analysis, as this is preparative chromatography.

I have been using the mobile phase 60 hexane: 40 ether: 4 acetic acid with a large sheet of filter paper to help equilibrate.  I also used grease to ensure a good seal with the chamber top.

My results keep showing that the first plate I run will have a very uneven solvent front and thus a poor sample separation.  However, if I use a new plate with the same sample plated in the same exact chamber and mobile phase, I seem to be having an adequate separation.

Has anyone had any issues like this? Any suggestions on how I can limit this from happening?


Thanks a ton!

BB