Chromatography Forum

I am working on a compound that is 152 amu. Infusion of this compound does not yield the appropriate ion but does yield an ion at 175. This appears to be my compound with a sodium adduct. My usual attempts to isolate the compound have not worked so I optimized on 175. The compound is a ethyl-R with R being 96 amu. Upon optimization it yielded a product ion of 119. Now could the 119amu be my 96+23amu and the sodium adduct has carried through in the MS/MS method on the product? I have never seen this before and think it's impossible but could I be wrong? Has anyone seen this sort of phemomenon? typically I do everything in my power to not monitor compound+adduct and have only done it a few times when following a method that expressly says to.

I will attempt to infuse this tomorrow using heated nebulizer in attempt to eliminate this adduct but has anyone seen this before?

As fas as I know, sodium adducts normally give a mass 22 higher instead of 23. So is it sodium?

No luck. I was afraid I was chasing a ghost. I did not think this compound would ionize but was asked to check it out because the HPLC method just did not provide the sensitivity needed. As far as the sodium adduct is concerned, in positive mode it usually shows up as M+23 or M+1 +22.

I have seen adducts (typically sodium) carry through ISCID so can't see any reason why it won't through a collision cell.

On a similar but more curious note, I am sure I'm seeing a sodium adduct forming after isolation in the quad of a q-tof system - so isolating the [M+2H]2+ with a window of 3amu either side, and actually seeing what we believe is the [M+Na]+ in the product ion spectrum (supported by accurate mass). Any ideas how this can happen?