Recently we have had a problem with one of our GC columns (MDN-5) where we were getting a rising basline at elevated temps. (250 degs). The column was only 2-3 months old and I was just wondering what could be causing the column to degrade so quickly?
By Anonymous on Tuesday, July 22, 2003 - 06:31 am:
There are numerous reasons for degrading column performance, i.e. contaminated carrier gas, sample contaminants, improper sample solvents, i.e. contain strong acids or bases, contamination in the linlet liner bleeding slowly onto the column, and several others which I am sure I have forgotten. To be of more help we need more informatoin about whats beiong analyzed, conditions, etc.
By Tristan Van Emmerik on Tuesday, July 22, 2003 - 08:42 pm:
The samples analyzed are either hormones (estradiol, estrone, etc.) or organophosphate pesticides & their metabolites. Both are derivatized with MTBSTFA before analysis. The injection volume used is 0.5 ÁL. We are running in the splitless mode we start at 70 deg and finish at 250 deg. Could the degradation be caused by excess derivatizing reagent?