Hi, Paul,

this nis a good idea to use headspace volatiles with GC/MS for hotmone measuer. But, honestly, I do not see how you can do this technically in the same samples. You need to have enough amount of materail for measure, so, you need to take quite a lot materail form your sample. The process of taking materail will have effect on next time point.

Moreover, if you plant to use leaf, for example, different cell layers/ tissue may hacve a different contents of the hormones.

And, finally, 3d point: how you plan to quentify results? Quantification per fresh weight may not correctly reflect real picture because different cell types have a different volume/weight. So, you will have some "average" number, but it is realy importnat to measure hormones löevel with cell resolution..

You can try antibody against SA and MeJ. But, in this case you can not use same smapels several time.

Good luck!

Dear, review this paper http://www.nature.com/nprot/journal/v5/n6/abs/nprot.2010.37.html

greetings

Hi Paul,

It is not a good idea to use headspace sampling. A better approach is a flow through open system See my paper on this in ResearchGate to measure ethylene emission from plants.

With headspace, oxygen and CO2 mixing rartios change the longer the expirement lasts, influencing respiration as well as photosynthesis. This gives erroneous results. Avoid this by sampling with an open flow system from which you take your samples for GC-MS. In ethylene physiology in plants this has been a longstanding discussion, until I published the paper on open flow sampling. Headspace was left as a technique for ethylene measurements usung GC-FID.

CHeers,

Frank