I have an issue 1100 HPLC. The retention time is shifting. I changed the station pump, the needle, the needle seat, the column, the seal rotor, and the guard. The issue continues. Some ideas and recommendations.  


Parents Reply Children
  • If we assume that system is ok( generally propotional valve/ check valve/ no bubble in line/sample loop is not over loaded/ no leak/constant flow/ no pressure variation) then this problem may link with some chemical related.

    I will suggest use new mobile phase and condition this new column with new mobile phase at least 10 to 12 hour.After that run sample to see repeatability n RT..

Was this helpful?