peaks in void volume

[cahuset]

Any suggestions about why I might have a large peak in the void volume of my LC/MS/MS runs?
Do I have overload and therefore this analyte is not retained?

[tom jupille]

Need more information in order to comment:
- Are you running a pure standard or an actual sample?
- Are you looking at the total ion chromatogram or a specific ion?
- Do you have a big peak at t0 and then your analyte peak, or just one huge peak starting at t0?

[cahuset]

this was actual samples (extracts from biota)
and it was the specific transition (from MS/MS) that had the strange peaks
And there are two peaks, the first one at t0 and the second one at the normal retention time.

[Uwe Neue]

Please see the note that I just posted to Ericz. It could be that your sample is dissolved in an organic solvent, and your sample migrates through the column unretained.

[Uwe Neue]

Or you got still so much junk in your sample that you see every mass in your unretained peak.