Headspace vials

[Mac2]

Has anyone investigated the difference between headspace vials?
Is it better to go 10 in 20 or 5 in 10?
Also, are screw caps as good as crimped caps?

[Mac2]

Also will a 3 mL loop fill give me 3 times bigger peaks than a 1 mL??

[chromatographer1]

My paper in Analytical Chemistry June 1997 shows the effect of the same sample in 20, 10, and 3.35mL vials.

3mL loop fill will not give you 3 times bigger peaks. You will generally be unable to focus the sample and peaks will be 3 times as WIDE rather than as TALL, and resolution will suffer greatly.

You may wish to investigate SPME if you wish to lower your detection limit by 3-5 orders of magnitude.

There are inherent issues of greater variability with SPME, but rather than not detecting a 1 ppb peak, having a 15% RSD of a 1 ppb peak isn't so bad.

If you CAN discuss the particulars of your analysis I would be glad to offer assistance.

best wishes,

Rod