How to analyze dissolved N2O in water with GC-ECD

[akellacs]

Hello,
I am trying to measure N2O Using GC-ECD with PLOT Q column without head-space arrangement.
I need to measure in aqueous phase.
Kindly suggest how I can go about.

[nick576]

Hello akellacs,
Maybe more info from you would help. So you do not have "headspace arrangement". How are you delivering samples to the GC, ie injection? The most common way to measure dissolved N2O (in water, seawater, slurry) is by headspace. So if you have a water sample, a headspace is introduced (high purity helium for example). The sample is then allowed to equilibrate (at known temp, shaking helps) between gas and water phase. The gas phase N2O concentration is analysed. With known solubility you can calculate dissolved N2O concentration in your samples. We do this occasionally for seawater, sediment slurry samples. Also there are N2O electrodes out there, that are very sensitive and could be used in situ.

Cheers, Nick