You are correct. My Friday frazzled brain is stuck in pharmacology mode so I was thinking not of free hydroxide concentration but in terms of potential exchangable groups being sequestered by the buffer. No more posting on Friday. My apologies.
Katherine On Fri, May 11, 2012 at 12:23 PM, Jacob Keller < j-kell...@fsm.northwestern.edu> wrote: > Just to make sure I understand pH correctly: isn't it true that the [OH-] > should always be the same at a given pH (by definition)? > > JPK > > On Fri, May 11, 2012 at 11:48 AM, Katherine Sippel < > katherine.sip...@gmail.com> wrote: > >> That is probably because you pH Tris with HCl rather than HEPES with >> NaOH. The Ksp for Zn(OH)2 is 3x10^17 so the excess hydroxides are probably >> what are killing your solution. >> >> Cheers, >> >> Katherine >> >> >> On Fri, May 11, 2012 at 11:43 AM, Rajesh Kumar <ccp4...@hotmail.com>wrote: >> >>> If there is no cure , then fine. >>> pH may not be the answer as it doesn't Happen with TRIS buffer pH 7.6. >>> Thanks to every one >>> Rajesh >>> >>> >>> ------------------------------ >>> Date: Fri, 11 May 2012 12:35:45 -0400 >>> From: dj...@cornell.edu >>> >>> Subject: Re: [ccp4bb] zinc with HEPES >>> To: CCP4BB@JISCMAIL.AC.UK >>> >>> >>> >>> There is no cure for HEPES. >>> >>> >>> >>> >>> -- >>> ======================================================================= >>> All Things Serve the Beam >>> ======================================================================= >>> David J. Schuller >>> modern man in a post-modern world >>> MacCHESS, Cornell University >>> schul...@cornell.edu >>> >>> >> > > > -- > ******************************************* > Jacob Pearson Keller > Northwestern University > Medical Scientist Training Program > email: j-kell...@northwestern.edu > ******************************************* >
