Chromatography Forum

The problem with the compound decomposition

Hi,
I hope somebody could give me a help. Now I am using GC-FID to test the one compound purity. But I found the problem:
The compound boiling point is 102 C. it is very easy to decompose to other two compounds.
recently the method was set as following:
Initial rate temp wait
50 3.0
15 150 0
30 220 0
Inject port temp 105C. detect port temp 150C
Split Ratio is 46:1,
But at this condition, still small parts of compound had been decomposed.

Irene-

Perhaps GC is not the best methodology here. Is your compound better suited for HPLC? You did not post enough information (sample prep/matrix, sensitivity required, etc.) for more thorough help in your problem.

An additional thought, if you know the identity of your decompostion products and can obtain standards of them, maybe you could quantitate your peak of interest via mass balance.

Just my two cents.

-Jeff

You may try cool on-column injection, i.e. injection at a relatively low temperature. You may modify the split/splitless injector to on-column injection by an appropriate tapered liner.