Wash buffer pH - (Nov/26/2009 )
I am doing an ELISA with this kit - http://www.ebioscience.com/ebioscience/spe..._88/88-7324.pdf
It doesn't come with the wash buffer. It recommends a pH of 7.4, tween 20 0.5%, pbs.
I have found a wash buffer that meets all of those requirements except that it is pH 7.5.
Will this make a big difference or is it okay?
Thanks!
It will be okay, 
and can you garantee that the pH measurement is 100% OK
As far as i understand the pH is chosen as Generally after binding of antigen and antibody or both we wash with buffer which could be in the range of ph: 7.0-7.5.
this is considered good because it's almost neutral pH, where there is least chance of disturbing the binding of antigen, antibody or both.
May not be compulsary but there has to be some logic or else all wont use that pH universally!!!
Best luck!