I am working on a project where some biological material is extracted in acetonitrile, but we do not see DA or 5-HT in the GC/MS after derivitization. It could be a failure of the reaction or perhaps it is just insoluble in acetonitrile.
According to their structure they should be. Beware that the hydrochloride may have a different solubility.
Thanks! I found this morning that with the addition of tiny amounts of water, even the HCL salt is quite soluble in acetonitrile. Since our extraction is of undried tissue with water present, I am confident that we should be getting these compounds out, so the problem must lie with the derivitization or GC/MS...
How are you performing the derivatization? MSTFA should do the trick for that compound...
We used BSTFA, but it could be that with traces of water the reaction did not work...
Yeah no, I am pretty sure water will kill the reaction (or seriously hinder it). I have always dried my samples down, perform an extraction, dry it down again, and then perform the derivatization. Is it necessary to use wet tissue?
I guess we will try it again with dried samples, although we were concerned about losing some volatile substances. The catecholamines should be fine though.
Yeah, you will lose the volatile compounds. Its an unfortunate side effect of drying your samples, but you could perform another series of analyses (ie, headspace, if the volatile analytes are amenable to it. Thats not something I've done though...). Good luck!
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