Chromatography Forum

hi all,

I am a grad student trying to analyze ppm amts of CH4 in CO2. I was thinking of collecting my samples in autosampler vials so that I can use a autosampler to do the work for me. ( The GC is away from my sampling point.)

I am kind of short on money and would like to save on crimping tools if not needed. Recently I came across SnapCap seals, where u presumably just snap the seal (cap and septum) without using crimper/decapper..

This looks to be a very simple solution compared to crimping vials...( i have to admit that i am a newbie to GC and have never crimped a vial b4 )

Can anyone tell me if the gas tightness of SnapCap seals is comparable to that of the aluminum cap seals ?

It seems like a nice idea but I doubt that it would work. I remember in the distant past that someone tested several autosampler vial/cap combinations and found that there was significantly greater solvent loss from the snap-caps than from the crimped tops during the test period. Gases would probably leak out even faster. Sorry to ruin your idea!

[quote="skunked_once"]

thanks for the reply...are there any other crimpers in the market that cost <100 $ ?

Try looking on e-bay We have sold a few second hand ones there in the past.