By Anonymous on Friday, November 14, 2003 - 07:56 pm:
Dear all,
We are facing a problem in LCMSMS during the analysis of Ubiquinone and related compounds. We are using PE-SCIEX API 3000 (Turboionspray and APCI).
There was no ionization for Ubiquinone.
Is anybody came across a similar problem?
Your valuable suggestions are welcome.
Advance thanks.
By MG on Saturday, November 15, 2003 - 08:58 am:
Yep, some compounds don't ionize well with ESI or APCI. I've had a few compounds that just don't work at all. In that case, photoionization with LC/MS, or EI / CI with GC/MS may be better choices.
You could try ESI(+) with about 20 micromolar of sodium acetate (check the literature though) in the mobile phase, to see if it will make sodium adducts.
You could also try APCI(-) again and see if you can make a radical M- ion. I once had a known compound do this, where it could neither gain nor lose a proton.