Topics in GC & HPLC

Lower elution temperature will make a component elute at a more stable baseline, which can be especially of interest if there is a lot background developed. Many methods are inherited from time where column inertness was not controlled as well as we do now. Often thicker films were chosen to get sufficient symmetrical peaks. Thick films will give high elution temperatures and they will bleed a lot.

Today’s GC Columns (implementing Rxi-technology) have MUCH higher inertness, so you do not have to use a thick-film to get a good peak.. Using a 2x thinner film reduces bleed about 50% AND reduces elution temperature by approx 16 degrees... Lowering elution temperature by 16 degrees will also reduce the background a additional factor 2.

In total, the background signal will be lowered a factor 4 providing highest signal/noise, a faster analysis and you can use the same analysis conditions (easy to try!) Check Restek's GC program if your phase has an Rxi-equivalent with thinner film