[HS-GC-FID] Styrene in isooctane problem

[notqual]

Hello everyone !

My laboratory has problem with styrene peak in matrix as isooctane and 95% EtOH.
It's impossible to quantify of styrene or integrate peak. Peak is fronting and concentration doesn't change the result, always the same.

We use:
ISTD: Toulene in DMSO,
Calibration standards: Styrene in DMSO.
Column: DB-5MS

I've changed DMSO to DMA but it doesn't change anything.

We also quantyficate styrene in matrix as 3%CH3COOH, 10%,20% and 50%EtOH - here we receive perfect symmetric peaks.

I really don't know what kind of problem it is.

(sorry for my English )

[Peter Apps]

Possibly the peak that you think is styrene is something else. Try eliminating components of the mixture one by one to see if the peak disappears.

Also you have a multicomponent matrix that includes water and high boiling solvents. This is likely to cause all sorts of peak distortions.

Peter

[rb6banjo]

I think it might be helpful to us if you could upload some graphics of what you are seeing in your chromatograms. Please be careful to describe what each image represents. You can get information on how to upload images by looking here:

viewtopic.php?f=2&t=12659