I need a phosphate buffered saline with magnesium and a PH of 5.5; can I make that easily, or can you please tell me who could make that up?
Make 1 liter each of two separate 20X solutions
Solution 1 :
348 mM Na2HPO4 46.86g
70 mM Na2H2PO4 9.66g
70mM KCl 5.2g
18mM MgCl2 3.6g
2.74 M NaCl 160g
Dilute 5 ml of each of solutions 1 & 2 in 90ml of dionized water to get 1X PBS
(check and adjust pH before you bring it up to full volume)
Do not refrigerate or the Mg will precipitate.
Additionally, if you require very large volumes of it, Invitrogen offers a custom media/buffer service.
Not as much fun as making it up yourself however.
I looked up from google and it looks like people really use phosphate buffer with pH around 5.5. I was wondering how much buffering capacity PBS has at that pH because the two lowest pKa's of phosphate are at 2.2 and 7.2?
Very much appreciated.
This approach looks like it will work (unlike mine).