Phosphate buffer pH=7 + ACN = Precipitate?

[demi_lune]

Hello,

I would like to know if phosphate buffer at pH=7 can precipitate with ACN? if yes what is the proportion of ACN maximum to have for that's not precipitate.

Thank you.

Julien

[Uwe Neue]

The solubility of buffers depends on concentration of the organic solvent, the type of buffer, and also on the counterion. For some concrete information, look for A. P. Schellinger and P. W. Carr, LC/GC North America 22 (6) 2004, 544-548.

If you are talking specifically a phosphate buffer in 100% acetonitrile... Yes, it is rather insoluble in MeCN.