Ghost Peak after Column Washing with 0.1% TFA

[kalsang]

Dear friends,

I was consistently getting 'ghost peak' and suspected contamination in my column {BEH Shield RP-18 (100x2.1) mm, 1.7 micron}.

I washed the column with A 90% to B 90% for a gradient time of ten minutes, in which A is 0.1% TFA in water and B is 0.1% TFA in acetonitrile. Unfortunately, instead of solving the problem, I got three more ghost peaks. They are now appearing even after washing with 10% aqueous ACN followed by 100% ACN.

Please Help!

[tom jupille]

Run the "three blank gradients" test to see if the cause is contaminated mobile phase. It's described in the "mini tutorial" in the tophread on the board.