"dirty" gradient end at low wavelengths

<p><span>I'm running a 10 mM Ammonium Phosphate/ACN gradient (210 nm) and have determined that the dirty "rollers" I see in one instrument near the end of the ~20 min. gradient (with repeated blanks) are in this instrument (mobile phase run on a different Acquity gives clean gradient-end). What is the recommended approach for cleaning this? Isopropanol? We don't have the THF-compatible systems here. </span></p>


  • lizh

    Hello there:

    I am going to be a bit cautious, as not sure I know what "rollers are" !!

    Can you share the chromatogram and so we all can see.

    If the mobile phase is clean and it is the system, I would like to narrow down before we make a decontmmination recommendation. But a picture seaks 1,000 words.

    Also when you checked the mobile phase, did you similarly eliminate the column?

    Many TX