Maximum sensitivity for tracer gas sampling

[osp001]

Of the compounds that are either a gas or liquids that are sufficiently volatile at STP to be used as a tracer, which compound/detector coupling offers the greatest sensitivity?

I was thinking halogenated compound + ECD, but I am unsure as to whether MS offers greater sensitivity than ECD.

In this experiment, sample quantity is virtually unlimited, and there are reasonable restrictions with respect to the toxicity of the tracer.

[AICMM]

osp001,

ECD is very sensitive when the tracer is right. SF6 is one example, can easily go to ppt levels. There are also some perfluoroalkanes that might work. Two other things to consider: 1) is the sample getting collected and coming back to the lab? 2) What is the balance gas and can you easily separate the balance from the tracer?

#1 because complexity is an issue. In order to run MS you need lots of supporting hardware. #2 because you may need to separate tracer from the balance gas. Using SF6 and ECD as an example, O2 will also respond on ECD so you need to separate the O2 from the sample in order to use an ECD.

I can discuss further if you desire.

Best regards,

AICMM