Na2Hpo4 , NaH2po4 or both in Church buffer ?! - (Jul/22/2004 )

hello all

Does anybody know if it's absolutly necessary to use both Na2Hpo4 and NaH2po4 to make sodium phosphate solution for Church buffer preparation or i could simply use 0.5 M Na2Hpo4 only (without NaH2po4) to do Church buffer ? there are many different recipes for church buffer which make me confusing and perplexed !!

thankx very much

Yes, you need both. check this protocol
http://www.molgen.mpg.de/~soldatov/protoco...ol/09/09_06.doc

OK , thanx a lot. But why we need the two sodium phosphate solutions if we can obtain the 0.5 M from Na2Hpo4 or NaH2po4 only ?