EtOH + PBS = precipitation?

[Jim Hutchins]

LU Pin (bolupin at uxmail.ust.hk) wrote:
: Recently when I tried to prepare 95% ethanol in PBS, I always got the 
: same problem. When PBS was added into abs. ethanol, the solution became 
: turbid. Later, some white precipitate formed. Shaking or vortexing during 
: PBS addition did not help. The PBS I used contains NaCl, KCl, Na2HPO4, 
: KH2PO4. Anyone knows what's wrong or how to avoid this? Thank you very much.

Why are you trying to prepare 95% EtOH/PBS?  As far as I'm aware, phosphate
precipitates under the conditions described.

If you tell us the intended use, maybe we can suggest a substitute.
--
Jim Hutchins
Assoc Prof Anatomy, Asst Prof Neurology (Research), Univ Mississippi Med Ctr
http://fiona.umsmed.edu/~hutchins/    ***    E-mail:   hutchins at umsmed.edu