running 10 mMol sulfuric acid into a triple quad
Posted: Thu Mar 07, 2013 2:04 am
by sepscientologist
I want to run a biorad H form ion exclusion column into an lcms. I run with
10 mMolar sulfuric acid. Will that kill my source?
It's a Sciex 3000.
Re: running 10 mMol sulfuric acid into a triple quad
Posted: Fri Mar 08, 2013 2:18 pm
by lmh
Yes.
Almost certainly. I once, in my tender youth, tried an even lower concentration into an Agilent source, on the grounds that sulphuric acid is volatile. What I forgot is that it's a strongly oxidising acid and doesn't need any help to oxidise even high-quality stainless steel components in the heat of a spray chamber.
The bits of the chamber that didn't go black, went green and gooey. Fortunately I noticed after only 30min, and after an embarrassed telephone conversation with Agilent (who spoke very slowly, a little bit LOUDLY, and in simple, easy words...) and a great deal of washing, the mass spec survived with only slight pitting of the spray cone. But I really, really wouldn't recommend it.
Gave beautiful sulphate adducts of the expected product, though!
Re: running 10 mMol sulfuric acid into a triple quad
Posted: Fri Mar 08, 2013 7:34 pm
by Camisotro
I'd be careful about your HPLC components too.
I seem to recall reading about some sort of cartridge you put between the column and MS that exchanges out the strong acid.
Another option is to try and adapt the method to work with, say, TFA or HFBA. These are bad for ion sources too but not nearly as bad as destroying it.