MgATP stock solution - how? (Oct/04/2006 )

Hi everybody!
I need to prepare a stock solution of MgATP from Na2ATP and MgCl2. Does anybody work with this? I know pH is a big deal; and also, I would like to quantitate the ATP spectrophotometrically, how do I do it? Thanks!!!

---

pH should be adjusted with NaOH

what I understand from your question is that you will substitute quantitativly Na+ against Mg++;
it depends on pH, as well as concentartions of Na-ATP and MgCl2; what you need is the corresponding dissociation constants; the best way is to use software such as Eqcal (I think also online possible); or if you do not like calculation, you have to use MgCl2 in strong excess;

---