Strange extra peaks before the compound (GC-MS/MS)

[Remu]

I have faced a problem which I never had before. I'm analysing PAH compounds and use GC-MS/MS. After the ion source cleaning I run some standards and just before the analyte peak there is every time another peak which got bigger after the cleaning procedure. Do you think it's the contamination problem or something else? I appreciate your opinions

[Don_Hilton]

A bit more detail may help. What spectral information do you have about these odd peaks? how does the peak shape look. Some pictures and a bit more detail could help us out.

[HW Mueller]

What are the retention factors (k) of the peaks?

[AICMM]

REmu,

Splitless or split?

Best regards.

[Remu]

Thanks for your answers. After my question we cleaned the injector part, cut the column and replaced all the injector parts (liner, gold plate, o-ring, septum). Despite of that the solvent standard peaks are bad, it means tailing and co-elution and compound which I can't separate from each other, because it's only one big broad peak without any proper shape. My collegues believe the problem has to be either at the injector or column. At the monent we ordered a new column and hopefully next week can try it. The strange thing here it that the standard matrix curve (fish) looks pretty:? Maybe we have cut the column (30 m) too many times and it can't separate the compound anymore ??