Hello all,

I'm hoping that someone can point me in the right direction here. I'm running EPA method 515.4 with DB-5MSUI 60meters 0.25mm ID and 0.25 um film thickness. The Aciflourfen and Dinoseb loose sensitivity before a complete run is finished (maybe get about half way through a 50 injection run before the QC starts failing). I know that cutting the column will bring it back but I would like to have a solution that will get me through the whole run before this is needed. I have also tried a Rtx-1701 for this method but I run into problems with an interfering peak for Dalapon. What columns are people using for this method?